Though amply described, alcoholic pancreatitis continues to stir controversy. One of the most deb... more Though amply described, alcoholic pancreatitis continues to stir controversy. One of the most debated points is whether it is a chronic disease since onset or progresses to a chronic form after repeated episodes of acute pancreatitis. Histologic studies on patients with pancreatitis have clearly shown that it is chronic since onset and that if necrotic acute pancreatitis develops in an alcoholic, it occurs in a pancreas damaged by chronic lesions. While the possibility cannot be wholly excluded that alcohol-related acute pancreatitis may develop in the absence of chronic lesions, such an occurrence would be rare. In addition to alcoholism, genetic factors play a determinant role in the pathogenesis of the disease. Genetic studies have suggested that in hereditary pancreatitis mutation of the cationic trypsinogen gene and serine peptidase inhibitor, Kazal type 1 (SPINK1) genes mutations of the may have pathogenetic importance; however, studies on alcoholic pancreatitis have produced ...
The aim of this work was to investigate whether specific receptors for atrial natriuretic factor ... more The aim of this work was to investigate whether specific receptors for atrial natriuretic factor (ANF) are present in ventricular cardiomyocytes and aortic smooth muscle membranes. 125I-ANF was employed to test the binding of the radioligand to isolated rat cardiomyocytes. Calcium-tolerant ventricular cardiomyocytes were obtained by retrograde perfusion with collagenase. 125I-ANF binding to cardiomyocytes was highly specific (70-80%) with a KD value of 72.6 pM and a Bmax of 9.37 fmol/mg protein. In other studies, 125I-ANF binding was investigated with a membrane preparation obtained from calf thoracic aorta, from which the endothelium had been previously stripped off. In this preparation too the interaction of 125I-ANF (70-80%) was highly specific, with a KD value of 70.4 pM and a Bmax of 8.78 fmol/mg protein. These results suggest that specific receptors to atrial natriuretic factor are present both in isolated rat cardiomyocytes and in the smooth muscle of calf thoracic aorta. Thi...
We have found that calcium stimulates, in a dose-dependent manner, the binding of opioid to kappa... more We have found that calcium stimulates, in a dose-dependent manner, the binding of opioid to kappa and delta receptors in sarcolemma from rat's ventricles isolated by hypotonic lithium bromide shock. Opioid binding was measured using [3H]-diprenorphine as a radioligand. The delta-selective agonist [D-Ala2, D-Leu5]-enkephalin and the kappa-selective agonist U-50, 488H both inhibited control and Ca(2+)-stimulated [3H]-diprenorphine binding to the sarcolemma, whereas [D-Ala2,MePhe4,Gly-(ol)5]-enkephalin was ineffective. The stimulatory effect of calcium increased the maximal binding capacity without affecting the affinity of the receptor for the ligand.
The activity of the azide-insensitive Ca2+-dependent ATPase (highly enriched in myofibrillar ATPa... more The activity of the azide-insensitive Ca2+-dependent ATPase (highly enriched in myofibrillar ATPase activity) was studied in specimens of both right and left atria which were taken from patients with ischemic and/or valvular heart disease during coronary by pass and/or valvular substitution. A significantly lower enzymatic activity was found in atrial specimens from patients with left ventricular heart failure in comparison to the atrial fragments obtained from the patients with normal heart function. Such an inhibition reflected a significant increase in the Km of the enzyme for ATP and was associated with a concomitant reduction in Vmax, both more evident in the left atrial fragments. Moreover, tissue homogenates of atrial specimens from failing hearts exhibited a lower protein SH group content when compared to the atrial homogenates from the heart with normal left ventricular heart function.
Immunoreactive dynorphin B-like material (ir-dyn B) was detected in acetic acid extracts of human... more Immunoreactive dynorphin B-like material (ir-dyn B) was detected in acetic acid extracts of human atrial specimens and of rat, rabbit and guinea-pig atria and ventricles by a validated radioimmunoassay. Levels were high in rabbit atrium (66.76 +/- 7.04 pmol/g) but lower and superimposable in human and rat atria (28.18 +/- 3.20 and 30.22 +/- 2.45 pmol/g, respectively). Gel permeation chromatography revealed ir-dyn B eluting close to column exclusion and in forms with an apparently higher molecular weight than authentic dyn B in human and rat samples. In contrast, almost all the immunoreactivity from rabbit and guinea-pig acetic extracts eluted as a single peak in the region of standard dyn B. Reverse-phase high performance liquid chromatography of the pooled gel chromatography fractions of this peak showed up a molecular form with the same retention time as authentic dyn B and a second minor peak of unknown immunoreactive material eluting three fractions earlier. Digestion with carboxypeptidase B excluded the hypothesis that this latter could be dyn B-Arg14. Therefore, it might be a metabolite of endogenous dyn B recognized by the antibody used in this study.
Some acute phase proteins are associated with both ischemic events and traditional risk factors. ... more Some acute phase proteins are associated with both ischemic events and traditional risk factors. Since they are strongly interrelated, each of them partly reflects the characteristics of other proteins. This study was carried out to ascertain the specific preferential associations of some acute phase proteins with traditional risk factors for atherosclerotic disease. High-sensitivity C-reactive protein, fibrinogen and C3-complement were assessed in 288 unselected men aged 55-64 years. Three multiple linear regression analyses were performed, in which each of the three acute phase proteins was considered the dependent variable of both traditional risk factors and the other two proteins. The three acute phase proteins strongly correlated with each other. Moreover, C-reactive protein was independently associated with triglycerides (P<0.0001), age (P=0.0130), body mass index (P=0.0179), and acute (P=0.0280) and chronic (P=0.0582) inflammations (R2=0.17). Fibrinogen was associated with alcohol consumption (inversely, P=0.0001) and smoking (P=0.0598) (R2=0.06). Finally, C3 was associated with insulin (P<0.0001), cholesterol (P=0.0001), sedentarity (P=0.0028), glucose (P=0.0077), and systolic blood pressure (P=0.0124) (R2=0.28). When simultaneously studied in multivariate analysis, acute phase proteins have different preferential associations with traditional risk factors, a probable consequence of their involvement in different cellular activations and metabolic processes.
Though amply described, alcoholic pancreatitis continues to stir controversy. One of the most deb... more Though amply described, alcoholic pancreatitis continues to stir controversy. One of the most debated points is whether it is a chronic disease since onset or progresses to a chronic form after repeated episodes of acute pancreatitis. Histologic studies on patients with pancreatitis have clearly shown that it is chronic since onset and that if necrotic acute pancreatitis develops in an alcoholic, it occurs in a pancreas damaged by chronic lesions. While the possibility cannot be wholly excluded that alcohol-related acute pancreatitis may develop in the absence of chronic lesions, such an occurrence would be rare. In addition to alcoholism, genetic factors play a determinant role in the pathogenesis of the disease. Genetic studies have suggested that in hereditary pancreatitis mutation of the cationic trypsinogen gene and serine peptidase inhibitor, Kazal type 1 (SPINK1) genes mutations of the may have pathogenetic importance; however, studies on alcoholic pancreatitis have produced ...
The aim of this work was to investigate whether specific receptors for atrial natriuretic factor ... more The aim of this work was to investigate whether specific receptors for atrial natriuretic factor (ANF) are present in ventricular cardiomyocytes and aortic smooth muscle membranes. 125I-ANF was employed to test the binding of the radioligand to isolated rat cardiomyocytes. Calcium-tolerant ventricular cardiomyocytes were obtained by retrograde perfusion with collagenase. 125I-ANF binding to cardiomyocytes was highly specific (70-80%) with a KD value of 72.6 pM and a Bmax of 9.37 fmol/mg protein. In other studies, 125I-ANF binding was investigated with a membrane preparation obtained from calf thoracic aorta, from which the endothelium had been previously stripped off. In this preparation too the interaction of 125I-ANF (70-80%) was highly specific, with a KD value of 70.4 pM and a Bmax of 8.78 fmol/mg protein. These results suggest that specific receptors to atrial natriuretic factor are present both in isolated rat cardiomyocytes and in the smooth muscle of calf thoracic aorta. Thi...
We have found that calcium stimulates, in a dose-dependent manner, the binding of opioid to kappa... more We have found that calcium stimulates, in a dose-dependent manner, the binding of opioid to kappa and delta receptors in sarcolemma from rat's ventricles isolated by hypotonic lithium bromide shock. Opioid binding was measured using [3H]-diprenorphine as a radioligand. The delta-selective agonist [D-Ala2, D-Leu5]-enkephalin and the kappa-selective agonist U-50, 488H both inhibited control and Ca(2+)-stimulated [3H]-diprenorphine binding to the sarcolemma, whereas [D-Ala2,MePhe4,Gly-(ol)5]-enkephalin was ineffective. The stimulatory effect of calcium increased the maximal binding capacity without affecting the affinity of the receptor for the ligand.
The activity of the azide-insensitive Ca2+-dependent ATPase (highly enriched in myofibrillar ATPa... more The activity of the azide-insensitive Ca2+-dependent ATPase (highly enriched in myofibrillar ATPase activity) was studied in specimens of both right and left atria which were taken from patients with ischemic and/or valvular heart disease during coronary by pass and/or valvular substitution. A significantly lower enzymatic activity was found in atrial specimens from patients with left ventricular heart failure in comparison to the atrial fragments obtained from the patients with normal heart function. Such an inhibition reflected a significant increase in the Km of the enzyme for ATP and was associated with a concomitant reduction in Vmax, both more evident in the left atrial fragments. Moreover, tissue homogenates of atrial specimens from failing hearts exhibited a lower protein SH group content when compared to the atrial homogenates from the heart with normal left ventricular heart function.
Immunoreactive dynorphin B-like material (ir-dyn B) was detected in acetic acid extracts of human... more Immunoreactive dynorphin B-like material (ir-dyn B) was detected in acetic acid extracts of human atrial specimens and of rat, rabbit and guinea-pig atria and ventricles by a validated radioimmunoassay. Levels were high in rabbit atrium (66.76 +/- 7.04 pmol/g) but lower and superimposable in human and rat atria (28.18 +/- 3.20 and 30.22 +/- 2.45 pmol/g, respectively). Gel permeation chromatography revealed ir-dyn B eluting close to column exclusion and in forms with an apparently higher molecular weight than authentic dyn B in human and rat samples. In contrast, almost all the immunoreactivity from rabbit and guinea-pig acetic extracts eluted as a single peak in the region of standard dyn B. Reverse-phase high performance liquid chromatography of the pooled gel chromatography fractions of this peak showed up a molecular form with the same retention time as authentic dyn B and a second minor peak of unknown immunoreactive material eluting three fractions earlier. Digestion with carboxypeptidase B excluded the hypothesis that this latter could be dyn B-Arg14. Therefore, it might be a metabolite of endogenous dyn B recognized by the antibody used in this study.
Some acute phase proteins are associated with both ischemic events and traditional risk factors. ... more Some acute phase proteins are associated with both ischemic events and traditional risk factors. Since they are strongly interrelated, each of them partly reflects the characteristics of other proteins. This study was carried out to ascertain the specific preferential associations of some acute phase proteins with traditional risk factors for atherosclerotic disease. High-sensitivity C-reactive protein, fibrinogen and C3-complement were assessed in 288 unselected men aged 55-64 years. Three multiple linear regression analyses were performed, in which each of the three acute phase proteins was considered the dependent variable of both traditional risk factors and the other two proteins. The three acute phase proteins strongly correlated with each other. Moreover, C-reactive protein was independently associated with triglycerides (P<0.0001), age (P=0.0130), body mass index (P=0.0179), and acute (P=0.0280) and chronic (P=0.0582) inflammations (R2=0.17). Fibrinogen was associated with alcohol consumption (inversely, P=0.0001) and smoking (P=0.0598) (R2=0.06). Finally, C3 was associated with insulin (P<0.0001), cholesterol (P=0.0001), sedentarity (P=0.0028), glucose (P=0.0077), and systolic blood pressure (P=0.0124) (R2=0.28). When simultaneously studied in multivariate analysis, acute phase proteins have different preferential associations with traditional risk factors, a probable consequence of their involvement in different cellular activations and metabolic processes.
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