Dennis Liu
University of California, Irvine, Psychology, Graduate Student
- functionally unfixatededit
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ABSTRACT This study examined whether the effects of protein restriction and angiotensin converting enzyme (ACE) inhibition on the progression of renal failure are common or additive. Male Sprague Dawley rats (12 wks of age) underwent 5/6... more
ABSTRACT This study examined whether the effects of protein restriction and angiotensin converting enzyme (ACE) inhibition on the progression of renal failure are common or additive. Male Sprague Dawley rats (12 wks of age) underwent 5/6 nephrectomy and were randomized to 20% protein diet (PD) (n = 9), 20% PD+enalapril (5 mg/kg/day) (n = 10), 20% PD+felodipine (30 mg/kg/day) (n = 9), 6% PD (n = 9), 6% PD+enalapril (n = 9) or 6% PD+felodipine (n = 10). Protein restriction, enalapril or felodipine treatment all retarded progression of renal failure and development of glomerular lesions. Protein restriction and enalapril appeared to have additive effects in preventing glomerular sclerosis.
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Autoimmune processes are suspected to play a role in the pathophysiology of psychotic disorders. Better understanding of the associations between auto-immunoglobulin G (IgG) repertoires and clinical features of mental illness could yield... more
Autoimmune processes are suspected to play a role in the pathophysiology of psychotic disorders. Better understanding of the associations between auto-immunoglobulin G (IgG) repertoires and clinical features of mental illness could yield novel models of the pathophysiology of psychosis, and markers for biological patient stratification. We undertook cross-sectional detection and quantification of auto-IgGs in peripheral blood plasma of 461 people (39% females) with established psychotic disorder diagnoses. Broad screening of 24 individuals was carried out on group level in eight clinically defined groups using planar protein microarrays containing 42,100 human antigens representing 18,914 proteins. Autoantibodies indicated by broad screening and in the previous literature were measured using a 380-plex bead-based array for autoantibody profiling of all 461 individuals. Associations between autoantibody profiles and dichotomized clinical characteristics were assessed using a stepwise...
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Objectives: The COVID-19 pandemic poses significant risks to the vulnerable patient population supported by community mental health (CMH) teams in South Australia. This paper describes a plan developed to understand and mitigate these... more
Objectives: The COVID-19 pandemic poses significant risks to the vulnerable patient population supported by community mental health (CMH) teams in South Australia. This paper describes a plan developed to understand and mitigate these risks. Methods: Public health and psychiatric literature was reviewed and clinicians in CMH teams and infectious disease were consulted. Key risks posed by COVID-19 to CMH patients were identified and mitigation plans were prepared. Results: A public health response plan for CMH teams was developed to support vulnerable individuals and respond to the COVID-19 pandemic. This plan will be reviewed regularly to respond to changes in public health recommendations, research findings and feedback from patients and clinicians. Conclusions: The strategic response plan developed to address risks to vulnerable patients from COVID-19 can assist other CMH services in managing the COVID-19 pandemic.
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Background Web-based information and interventions for mental illness are increasingly being provided. There is an expectation that citizens have access to the internet and are competent in using technology. People with schizophrenia are... more
Background Web-based information and interventions for mental illness are increasingly being provided. There is an expectation that citizens have access to the internet and are competent in using technology. People with schizophrenia are often excluded from social engagement, have cognitive impairment, and have very limited income, all of which may reduce their use of technology. Objective This study aimed to investigate technology access, use of digital technology, and confidence in using technology among people with schizophrenia living in the community. Methods Face-to-face structured interviews with 50 people with schizophrenia (aged 18-65 years) living in the northern suburbs of Adelaide, South Australia, were conducted using an instrument designed to assess technology access and utilization. Results Most participants (42/50, 84%) owned a mobile phone, but only 58% (29/50) owned a smartphone. Two-thirds of participants (33/50, 66%) had access to the internet at home, using a sm...
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Previous culture studies have demonstrated that muscle cells autonomously express and cluster ACh receptors (AChRs) and that contact by neurites induces a reorganization of these clusters. We studied these phenomena in zebrafish embryos... more
Previous culture studies have demonstrated that muscle cells autonomously express and cluster ACh receptors (AChRs) and that contact by neurites induces a reorganization of these clusters. We studied these phenomena in zebrafish embryos where the same cells could be examined in vivo and in vitro, and where contacts between cells could be viewed repeatedly. Receptor clusters first appeared when the pioneer growth cones emerged from the spinal cord, were always associated with labeled branches, and developed normally in the presence of neuromuscular transmission blockers. When motoneurons were removed, the muscles failed to cluster receptors. In contrast, muscle cells grown in cell culture uncontacted by nerves clustered AChRs. Our results suggest that clustering of AChRs in living embryos is induced by the presence of neurites and does not occur in the absence of neuronal contact. We suggest that conditions in cell culture, which differ from those in the intact embryo, induce cluster...
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1. The activity of the two classes of motoneurones, primary and secondary, which innervate myotomal muscle fibres in the zebra fish, was monitored with electromyographic and intracellular techniques. 2. Simultaneous EMG and intracellular... more
1. The activity of the two classes of motoneurones, primary and secondary, which innervate myotomal muscle fibres in the zebra fish, was monitored with electromyographic and intracellular techniques. 2. Simultaneous EMG and intracellular recordings from muscle fibres showed that the activity of the two motor systems and of individual primary motoneurones can be distinguished by recording EMG spikes during swimming. 3. Measurements of EMG spikes demonstrated that primary and secondary motoneurones are co‐ordinately activated over a wide range of conditions during normal swimming. 4. During swimming the primary motoneurones within a given segment are usually co‐activated although they sometimes fire independently. 5. When different primary motoneurones within a given segment are co‐activated, they fire nearly synchronously. 6. We conclude that the primary motoneurones are used principally, although not exclusively, during fast swimming, struggling and the startle response, whereas sec...
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This study examined the prevalence of risk factors for cardiovascular (CV)-related morbidity and mortality in young people with psychosis aged 18 to 24 years. The study included 132 people aged 18 to 24 years who participated in the 2010... more
This study examined the prevalence of risk factors for cardiovascular (CV)-related morbidity and mortality in young people with psychosis aged 18 to 24 years. The study included 132 people aged 18 to 24 years who participated in the 2010 second Australian national survey of people living with psychosis. The 2009 World Health Organisation (WHO) Global Health Risks report was used as a framework to determine which specific risk factors were present in each in these young people. The risk factors assessed in this study were smoking, alcohol use, hypertension, overweight/obesity, physical inactivity, high blood glucose, high cholesterol and poor diet. Each risk factor was defined according to WHO criteria. A count of the total number of risk factors present for each participant was determined. Data for male and female participants were compared. Young men had an average of 2.9 (SD 1.2) risk factors. Young women had an average of 2.4 (SD 1.2) risk factors. The most common risk factors we...
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Research Interests: Bipolar Disorder, Obesity, Diet, Medicine, Comorbidity, and 15 moreOverweight, Population, Humans, Major Depressive Disorder, Blood Pressure, Female, Male, Body Mass Index, Adult, Cardiovascular Diseases, Motor activity, Antipsychotic agents, Psychology and Cognitive Sciences, Nutrition assessment, and Medical and Health Sciences
Objectives The aim of the present study was to document Australian policies on the physical health of people with mental illness and evaluate the capacity of policy to support health needs. Methods A search of state and federal policies... more
Objectives The aim of the present study was to document Australian policies on the physical health of people with mental illness and evaluate the capacity of policy to support health needs. Methods A search of state and federal policies on mental and physical illness was conducted, as well as detailed analysis of policy content and the relationships between policies, by applying the World Health Organization Mental Health Action Plan 2013-2020 as an evaluative framework. Results National policy attention to the physical health of people with mental illness has grown, but there is little interconnection at the national and state levels. State policies across the country are inconsistent, and there is little evidence of consistent policy implementation. Conclusions A coherent national health policy framework on addressing co-occurring physical and mental illnesses that includes healthcare system reforms and ensuring the interconnectedness of other relevant services should be prioritis...
Research Interests: Nursing, Mental Health, Health Inequalities, Australia, Applied Research, and 15 moreMental Health Policy, Health Services Research, Health Policy, Medicine, Comorbidity, Mental Illness, Health Care reform, Humans, Mental Disorders, Life Expectancy, Mental health services, Health Status, Action Plan, Australian Health, and Health Services Accessibility
Frontotemporal dementia is the third or fourth most common form of dementia in the 45-65 years age group. It causes significant morbidity as well as a six to eightfold increase in mortality risk. This article provides an overview of the... more
Frontotemporal dementia is the third or fourth most common form of dementia in the 45-65 years age group. It causes significant morbidity as well as a six to eightfold increase in mortality risk. This article provides an overview of the pathophysiology of frontal lobe function and the genetics of frontotemporal dementia. It also summarises the clinical features, diagnosis and management of frontotemporal dementia. While the clinical presentation of frontotemporal dementia was described as early as the nineteenth century, recent advances in genetics have resulted in greater understanding of the pathophysiology of this disease. While imaging may support the diagnosis of frontotemporal dementia, it is essentially a clinical diagnosis based on the presence of typical clinical features and the findings of neuropsychological tests. Clinical management of frontotemporal dementia remains a challenge and is largely centred on behavioural management. Pharmacological agents such as selective s...
Research Interests: General Practice, Psychiatry, Dementia, Australia, Quality of life, and 15 moreMedicine, Temporal Lobe, Humans, Pubmed, Clinical Sciences, Aged, Middle Aged, Atrophy, Frontotemporal Dementia, Disease Progression, Clinical Competence, Disease Management, Frontal Lobe, Severity of Illness Index, and Neuropsychological Tests
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Alcohol dependence is a worldwide problem with a great social and economic burden in many countries. A number of studies have suggested that BDNF (mature BDNF) and its precursor (proBDNF) play important roles in the alcohol dependence.... more
Alcohol dependence is a worldwide problem with a great social and economic burden in many countries. A number of studies have suggested that BDNF (mature BDNF) and its precursor (proBDNF) play important roles in the alcohol dependence. However, what roles of the mBDNF/proBDNF pathways play during the pathological process of alcohol dependence are not clearly understood. In our clinical study, peripheral blood was sampled from 30 male patients with alcohol dependence and 50 healthy males (as control). The protein levels of proBDNF, p75NTR, sortilin, mBDNF, TrkB and mRNA levels of BDNF, p75NTR, sortilin, and TrkB were detected in the peripheral blood in our study. We found that the protein levels of proBDNF and p75NTR were increased, but not the sortilin protein level; while the TrkB protein level was decreased in the alcohol dependence patients compared with healthy controls. Moreover, the mRNA levels of p75NTR and sortilin from the lymphocytes were slightly increased; while BDNF and...
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Individualized metacognitive training (MCT+) is a novel psychotherapy that has been designed to specifically target delusional beliefs in people with psychosis. It works by developing an awareness of the implausible content of delusional... more
Individualized metacognitive training (MCT+) is a novel psychotherapy that has been designed to specifically target delusional beliefs in people with psychosis. It works by developing an awareness of the implausible content of delusional beliefs, while also targeting the cognitive biases that contribute to their formation and maintenance. It was expected that MCT+ would lead to significantly greater reductions in delusional severity compared to a cognitive remediation (CR) active control condition. A total of 54 patients with a schizophrenia spectrum disorder and active delusions were randomized into four 2-hourly sessions of MCT+ (n = 27) or CR (n = 27). All participants completed posttreatment assessment, and only 2 participants did not complete 6-month follow-up assessment, resulting in MCT+ (n = 26) and CR (n = 26) for final analysis. The primary outcome measures of delusional and positive symptom severity were assessed rater-blind; secondary outcome assessment was non-blinded a...
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Schizophrenia is a complex mental illness affecting the normal functioning of the brain, interfering with the ability to think, feel and act. It can be conceptualised as a syndrome of accelerated ageing, with early onset of cardiovascular... more
Schizophrenia is a complex mental illness affecting the normal functioning of the brain, interfering with the ability to think, feel and act. It can be conceptualised as a syndrome of accelerated ageing, with early onset of cardiovascular disease and high rates of premature mortality. Telomere attrition increases with oxidative stress and is considered a biomarker of ageing. Previous studies have assessed abnormalities in telomere length in schizophrenia, but the results are inconsistent. The present study used a case-control design to assess whether people with schizophrenia have shortened telomeres, indicative of accelerated ageing. Subjects were all male, aged 25-35years, living in the same urban region of Adelaide, South Australia. Telomere length was measured using a quantitative real-time polymerase chain reaction (PCR) method. We found significantly shorter telomeres in people with schizophrenia relative to healthy controls. This is the first study to show telomere attrition ...
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Cognitively distinct subgroups of schizophrenia have been defined based on premorbid and current IQ, but little is known about the neuroanatomical differences among these cognitive subgroups. To confirm previous findings related to... more
Cognitively distinct subgroups of schizophrenia have been defined based on premorbid and current IQ, but little is known about the neuroanatomical differences among these cognitive subgroups. To confirm previous findings related to IQ-based subgroups of patients with schizophrenia in an independent sample and extend those findings to determine the extent to which brain volumetric differences correspond to the IQ-based subgroups. A total of 183 participants were assessed at the outpatient settings of Neuroscience Research Australia and Lyell McEwin Hospital from September 22, 2009, to August 1, 2012. Patients were classified using cluster analysis on the basis of current and premorbid IQ differences. Regional magnetic resonance imaging (MRI) brain volumes were compared among the IQ-based subgroups using analysis of covariance with intracranial volume and age as covariates. Wechsler Adult Intelligence Scale, third edition, scores; Wechsler Test of Adult Reading scores; Positive and Ne...
Research Interests: Psychology, Intelligence, Schizophrenia, Magnetic Resonance Imaging, Adolescent, and 15 moreMedicine, Brain, Humans, Schizoaffective Disorder, Female, Male, Young Adult, Middle Aged, Atrophy, Adult, Analysis of Variance, Age Factors, Psychotic Disorders, Cognition disorders, and Psychiatric Status Rating Scales
Chronic exposure to stressful environment is a key risk factor contributing to the development of depression. However, the mechanisms involved in this process are still unclear. BDNF has long been investigated for its positive role in... more
Chronic exposure to stressful environment is a key risk factor contributing to the development of depression. However, the mechanisms involved in this process are still unclear. BDNF has long been investigated for its positive role in regulation of mood, while the role of its precursor, proBDNF, in regulation of mood is not known. In this study, using an unpredictable chronic mild stress (UCMS) paradigm we found that the protein levels of proBDNF were increased in the neocortex and hippocampus of stressed mice and this UCMS-induced up-regulation of proBDNF was abolished by chronic administration of fluoxetine. We then established a rat model of UCMS and found that the expression of proBDNF/p75(NTR)/sortilin was up-regulated while the expression of mature BDNF and TrkB was down-regulated in both neocortex and hippocampus of chronically stressed rats. Finally, we found that the injection of anti-proBDNF antibody via intracerebroventricular (i.c.v.) and intraperitoneal (i.p.) approache...
Research Interests: Psychology, Neuropsychopharmacology, Medicine, Antibodies, Hippocampus, and 15 moreBrain, Dendritic Spines, Mice, Chronic Disease, Animals, Male, Depressive Disorder, FLUOXETINE, Neocortex, Chronic Stress, Food Preferences, Exploratory Behavior, Gene Expression Regulation, Psychology and Cognitive Sciences, and Medical and Health Sciences
There is increasing clinical and molecular evidence for the role of hormones and specifically estrogen and its receptor in schizophrenia. A selective estrogen receptor modulator, raloxifene, stimulates estrogen-like activity in brain and... more
There is increasing clinical and molecular evidence for the role of hormones and specifically estrogen and its receptor in schizophrenia. A selective estrogen receptor modulator, raloxifene, stimulates estrogen-like activity in brain and can improve cognition in older adults. The present study tested the extent to which adjunctive raloxifene treatment improved cognition and reduced symptoms in young to middle-age men and women with schizophrenia. Ninety-eight patients with a diagnosis of schizophrenia or schizoaffective disorder were recruited into a dual-site, thirteen-week, randomized, double-blind, placebo-controlled, crossover trial of adjunctive raloxifene treatment in addition to their usual antipsychotic medications. Symptom severity and cognition in the domains of working memory, attention/processing speed, language and verbal memory were assessed at baseline, 6 and 13 weeks. Analyses of the initial 6-week phase of the study using a parallel groups design (with 39 patients r...
Research Interests: Psychology, Molecular Biology, Clinical Trial, Medicine, Prefrontal Cortex, and 15 moreMolecular Psychiatry, Biological Sciences, Postmenopausal Women, Placebo, Estrogen, Frontal Cortex, Menstrual Cycle, Cognitive Function, Cellular and Molecular Neuroscience, Double Blind, Placebo Controlled Trial, Hormone Replacement Therapy, Adjunctive Treatment, Medical and Health Sciences, and crossover study
Depression is one of the most common chronic mental disorders, which is a leading cause of morbidity and mortality in patients. Depression often leads to offensive and defensive behaviours but the underlying mechanisms are not known. We... more
Depression is one of the most common chronic mental disorders, which is a leading cause of morbidity and mortality in patients. Depression often leads to offensive and defensive behaviours but the underlying mechanisms are not known. We propose that the aggressive behaviours in depression can be modelled in animal experiments. In this study, we successfully established a mouse model of depression using the chronic unpredictable mild stress (CUMS) paradigm and detected aggressive and social dominance behaviours in rodents by resident/intruder test and social dominance tube test (SDTT), respectively. The CUMS-exposed mice showed increased defensive, offensive and aggressive behaviours in the resident-intruder test. In the SDTT, these mice showed enhanced social dominance. These alterations were associated with reduced MAP-2 expression in the hippocampus while no difference in β-tubulin expression was detected. In addition, the treatment of anti-depressant fluoxetine reversed the aggre...
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This 13-week, double-blind study evaluated the efficacy and safety of the atypical antipsychotic paliperidone palmitate (recently approved in the United States) versus placebo administered as monthly gluteal injections (after two initial... more
This 13-week, double-blind study evaluated the efficacy and safety of the atypical antipsychotic paliperidone palmitate (recently approved in the United States) versus placebo administered as monthly gluteal injections (after two initial doses given 1 week apart) in acutely symptomatic patients with schizophrenia. Patients (N=388) were randomly assigned (1 : 1 : 1 : 1) to paliperidone palmitate 50, 100, or 150 mg eq. or placebo. As the 150 mg eq. dose was administered to fewer patients (n=30) than planned, meaningful and definitive conclusions cannot be drawn from the results of this group. The change from baseline in Positive and Negative Syndrome Scale total score at endpoint showed improvement in both paliperidone palmitate 50 and 100 mg eq. groups but was significant only in the 100 mg eq. group (P=0.019). The paliperidone palmitate 50 (P=0.004) and 100 mg eq. (P<0.001) groups showed significant improvement in the Personal and Social Performance score from baseline to endpoint versus placebo. Common adverse events (in…
Research Interests: Placebo Effect, Medicine, Dosage Form, Humans, Placebo, and 15 moreFemale, Clinical, Male, Anesthesia, Efficiency, Middle Aged, Adult, Clinical Psychopharmacology, Psychiatric Status Rating Scales, Adverse effect, Antipsychotic agents, Paliperidone, Pharmacology and pharmaceutical sciences, Positive and Negative Syndrome Scale, and Paliperidone palmitate
Cognitive impairment is a pervasive feature of schizophrenia, and is a major determinant of the functional disability that is characteristic of the disorder. However, research investigating whether patients with schizophrenia show a... more
Cognitive impairment is a pervasive feature of schizophrenia, and is a major determinant of the functional disability that is characteristic of the disorder. However, research investigating whether patients with schizophrenia show a deficit awareness remains unclear. The present study aimed to replicate and extend previous research comparing subjective and objective measures of cognition. . Thirty patients with a diagnosis of schizophrenia or schizoaffective disorder were administered the subjectively assessed Schizophrenia Cognitive Rating Scale (SCoRS) and the objective Brief Assessment of Cognition in Schizophrenia (BACS), which each assess overall global functioning and four specific neurocognitive domains (i.e., Verbal Memory, Working Memory, Processing Speed, and Reasoning and Problem Solving). Because deficit awareness may influence the likelihood of patients engaging in treatments designed to improve cognitive functioning, patients' attitudes towards such therapies were also contrasted with these subjective and objective measures of cognitive functioning. Patients' subjective appraisals did not significantly correlate with the objective neuropsychological assessments for global functioning or any specific neurocognitive domains. However, patients accurately deduced that their memory domains were more impaired than the other domains, and there was a trend for patients to exaggerate their Reasoning and Problem Solving deficits. This suggests that patients show some level of deficit awareness, when overestimating "deficits" for domains that are not impaired. Finally subjective, but not objective, measures of cognitive functioning correlated significantly with willingness to participate in cognitive-enhancing therapies. These results suggest that although patients' perceptions of their cognitive function are no substitute for objective neuropsychological test data, patients do possess a level of deficit awareness which may, in turn, influence willingness to participate in interventions such as cognitive rehabilitation.
Research Interests: Psychology, Neuropsychology, Cognition, Cognitive Neuropsychiatry, Medicine, and 15 moreProblem Solving, Neurocognitive, Humans, Female, Male, Awareness, Middle Aged, Cognitive Remediation, Adult, Cognitive Functioning, Cognition disorders, Case Control Studies, Neuropsychological Tests, BACS, and Medical and Health Sciences
Cognitive impairment is recognized as an important determinant of outcome in schizophrenia, but mental health services generally have little capacity to provide detailed neuropsychological assessments. Computerized testing would overcome... more
Cognitive impairment is recognized as an important determinant of outcome in schizophrenia, but mental health services generally have little capacity to provide detailed neuropsychological assessments. Computerized testing would overcome this difficulty, provided that such testing was equivalent to testing by a clinician. Given that negative symptoms can include impaired motivation and attention, it is also important to know whether computerized testing is valid in people with more severe negative symptoms. Our study was designed to compare clinician-administered and computerized testing of two domains commonly impaired in schizophrenia, verbal memory and verbal fluency. We also evaluated the effect of negative symptoms on performance on computerized cognitive tests. Sixty-two participants with schizophrenia completed clinician-administered and computerized verbal memory and verbal fluency tasks. The Positive and Negative Syndrome Scale assessed negative symptom severity. The study found no difference in cognitive performance associated with the method of test administration. This finding held regardless of the severity of negative symptoms. We found that computerized cognitive testing was equivalent to clinician-delivered testing in assessing verbal memory and verbal fluency. This finding was not affected by the presence of negative symptoms. Our results support the use of computerized cognitive testing for people with schizophrenia.
Research Interests: Psychology, Cognitive Science, Neuropsychology, Schizophrenia, Cognition, and 15 moreComputer Aided Design, Medicine, Memory, Humans, Neuropsychological Assessment, Female, Male, Mental health services, Cognitive Performance, Cognitive impairment, Adult, Neurosciences, Cognition disorders, Neuropsychological Tests, and Positive and Negative Syndrome Scale
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An increase in digitalis-like substances has been reported in deoxycorticosterone acetate (DOCA)-salt hypertensive rats. We hypothesized that the role of saline and unilateral nephrectomy in DOCA hypertension may be due to stimulation of... more
An increase in digitalis-like substances has been reported in deoxycorticosterone acetate (DOCA)-salt hypertensive rats. We hypothesized that the role of saline and unilateral nephrectomy in DOCA hypertension may be due to stimulation of endogenous digitalis-like substances. We investigated the effects of digoxin and DOCA alone and in combination in intact rats drinking water. Forty male Sprague-Dawley rats were used (body weight 223-298 g). Neither digoxin (40 micrograms/kg per day, by gavage, for 35 days, n = 10) nor DOCA (30 mg/kg twice a week, subcutaneously, for 5 weeks, n = 10) caused a consistent increase in blood pressure in intact rats drinking water. In contrast, combined digoxin and DOCA administration (n = 10) increased systolic blood pressure from day 18 of treatment onwards, to a maximum at day 34 compared with sham-treated rats (n = 10). There were no consistent changes in water intake, urine volume, urinary sodium or potassium excretion, or plasma sodium or potassium concentration with digoxin treatment. DOCA increased water intake and urine volume, and caused an initial decrease in urinary sodium excretion, but no change in urinary potassium excretion or plasma sodium concentration. Plasma potassium excretion was lower in DOCA- than sham-treated rats. Combined digoxin and DOCA administration in intact rats drinking water increased blood pressure significantly compared with either drug alone, raising the possibility that the mechanism by which nephrectomy and salt loading contribute to DOCA hypertension in the rat might be through stimulation of endogenous digitalis-like substances.
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To determine responses in renin gene expression in different tissues of two-kidney, one clip hypertensive Sprague-Dawley rats and the effect of NaCl loading, we developed a novel, highly sensitive quantitative polymerase chain reaction... more
To determine responses in renin gene expression in different tissues of two-kidney, one clip hypertensive Sprague-Dawley rats and the effect of NaCl loading, we developed a novel, highly sensitive quantitative polymerase chain reaction technique and measured renin mRNA at 19 and 40 days after clipping. Basal renin mRNA concentrations were 1575±127 fg/μg total RNA in kidney, 52±7 in hypothalamus, 7.9±0.7 in adrenal, and 4.7±0.5 in atria. In two-kidney, one clip rats, renin mRNA in the clipped kidney was increased 5.4-fold ( P =.00001) and 2.3-fold ( P =.001) on each respective day after clipping and in the unclipped kidney was decreased by 27% ( P =.01) and 38% ( P =.04). In adrenal, 3.9-fold ( P =.004) and 1.7-fold ( P =.02) increases were seen on days 19 and 40, respectively, and a decrease of 57% ( P =.02) was found in a hypothalamic block at day 19 but not at day 40. The decrease in hypothalamus was abolished by 1% oral NaCl, which reduced renin mRNA by 37% in the clipped kidney ...
Research Interests: Endocrinology, Molecular Biology, Biology, Medicine, Gene expression, and 15 moreInternal Medicine, Enalapril, Kidney, Hypertension, Hypothalamus, Animals, Male, Polymerase Chain Reaction, Clinical Sciences, Rats, Rat, Base Sequence, Molecular Sequence Data, Antihypertensive agents, and Cardiovascular medicine and haematology
Page 1. Clinical and Experimental Pharmacology and Physiology (1995) 22,493-495 PROCEEDINGS OF THE HBPRCA RENIN mRNA CONCENTRATION IN RAT HYPOTHALAMUS IS DECREASED BY ENALAPRIL Yi-kun ...
Research Interests: Endocrinology, Physiology, Chemistry, Gene regulation, Medicine, and 9 moreInternal Medicine, Enalapril, Kidney, Renin Angiotensin Aldosterone System, Hypothalamus, Medical Physiology, Clinical and Experimental Hypnosis, Clinical and Experimental Dermatology, and Pharmacology and pharmaceutical sciences
Page 1. Clinical and Experimental Pharmacology and Physiology (1997) 24, 727-729 SHORT COMMUNICATION HYPOTENSIVE EFFECTS OF PEPTIDE T IN CONSCIOUS RATS Cheng Wen, Dennis T Liu, Ming Li, Jurgen Michaelis," Geoffrey W Grigg* and... more
Page 1. Clinical and Experimental Pharmacology and Physiology (1997) 24, 727-729 SHORT COMMUNICATION HYPOTENSIVE EFFECTS OF PEPTIDE T IN CONSCIOUS RATS Cheng Wen, Dennis T Liu, Ming Li, Jurgen Michaelis," Geoffrey W Grigg* and Judith A Whitworth ...
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Research Interests: Endocrinology, Physiology, Kidney diseases, Medicine, Internal Medicine, and 15 moreKidney, Blood Pressure, Animals, Clinical, Male, Medical Physiology, Risk factors, Electrolytes, Rats, Body Weight, Risk Factors, Renal Artery, Sodium Chloride, Pharmacology and pharmaceutical sciences, and Kidney glomerulus
1. Two neuronal growth factors, nerve growth factor (NGF) and neurotrophin 3 (NT3), have been studied for their action on the developing and mature sympathetic nervous system. 2. Antibodies to each factor have proved useful as reagents... more
1. Two neuronal growth factors, nerve growth factor (NGF) and neurotrophin 3 (NT3), have been studied for their action on the developing and mature sympathetic nervous system. 2. Antibodies to each factor have proved useful as reagents for the detection and quantification of NGF and NT3. They have also proved valuable in uncovering the functional roles of each factor by their ability to neutralize the endogenous molecules. 3. Nerve growth factor acts on postnatal neurons to control neurotransmission, connectivity and survival. Like NGF, NT3 is synthesized by effector tissues and is retrogradely transported by post-ganglionic neurons to prevent cell death. However, the two factors have been shown to have quite distinct functions in mature neurons, indicating the existence of different signalling pathways. This differential action extends to secondary influences on satellite glia. 4. Pathological consequences result from excessive growth factor synthesis leading, in the hypertensive rat, to hyperinnervation and elevated blood pressure. Satellite glial cell synthesis of the factors and their receptors following peripheral nerve damage appears to be responsible for the establishment of inappropriate neuronal connections between sympathetic nerve terminals and sensory somata. 5. It is concluded that these potent factors control, by both coincident and independent mechanisms, sympathetic neuronal function throughout the life of the animal.