La multiplicité des critères susceptibles d’être utilisés pour évaluer l’adaptation comportementa... more La multiplicité des critères susceptibles d’être utilisés pour évaluer l’adaptation comportementale d’un animal à son environnement a motivé l’étude des relations entre réponses physiologiques et comportementales, dans l’espoir que l’identification de telles relations puisse simplifier l’évaluation du bien-être animal. La comparaison d’animaux placés dans des environnements différents et la comparaison d’animaux aux génotypes extrêmes suggèrent l’existence de relations entre certaines réponses physiologiques et comportementales. La possibilité de catégoriser certains animaux selon leur stratégie de réponse adaptative, caractérisée par des associations répétables entre réponses comportementales et physiologiques, conforte cette hypothèse. Cependant, les relations ainsi suggérées semblent difficilement généralisables : il n’existe pas de relation univoque entre les réponses physiologiques et comportementales d’un animal face à une situation perçue comme menaçante. En l’état actuel des...
We profiled individual differences in alcohol consumption upon initial exposure and during 5 week... more We profiled individual differences in alcohol consumption upon initial exposure and during 5 weeks of voluntary alcohol intake in female mice from 39 BXD recombinant inbred strains and parents using the drinking in the dark (DID) method. In this paradigm, a single bottle of 20% (v/v) alcohol was presented as the sole liquid source for 2 or 4 h starting 3 h into the dark cycle. For 3 consecutive days mice had access to alcohol for 2 h followed by a 4th day of 4 h access and 3 intervening days where alcohol was not offered. We followed this regime for 5 weeks. For most strains, 2 or 4 h alcohol intake increased over the 5-week period, with some strains demonstrating greatly increased intake. There was considerable and heritable genetic variation in alcohol consumption upon initial early and sustained weekly exposure. Two different mapping algorithms were used to identify QTLs associated with alcohol intake and only QTLs detected by both methods were considered further. Multiple sugges...
Stress is a generic term used to describe non-specific responses of the body to all kinds of chal... more Stress is a generic term used to describe non-specific responses of the body to all kinds of challenges. A very large variability in the response can be observed across individuals, depending on numerous conditioning factors like genetics, early influences and life history. As a result, there is a wide range of individual vulnerability and resilience to stress, also called robustness. The importance of robustness-related traits in breeding strategies is increasing progressively towards the production of animals with a high level of production under a wide range of climatic conditions and management systems, together with a lower environmental impact and a high level of animal welfare. The present study aims at describing blood transcriptomic, hormonal, and metabolic responses of pigs to a systemic challenge using lipopolysaccharide (LPS). The objective is to analyze the individual variation of the biological responses in relation to the activity of the HPA axis measured by the level...
Pig husbandry is known as an intensive breeding system, piglets being submitted to multiple stres... more Pig husbandry is known as an intensive breeding system, piglets being submitted to multiple stressful events such as early weaning, successive mixing, crowding and shipping. These stressors are thought to impair immune defences and might contribute, at least partly, to the prophylactic use of antibiotics. Robustness was recently defined as the ability of an individual to express a high-production potential in a wide variety of environmental conditions. Increasing robustness thus appears as a valuable option to improve resilience to stressors and could be obtained by selecting piglets upon their adrenocortical activity. In this study, we aimed at depicting the consequences of an acute social stress on the immune capacity of piglets genetically selected upon divergent hypothalamic-pituitary-adrenocortical (HPA) axis activity. For this purpose, we monitored neuroendocrine and immune parameters, in high- (HPA(hi)) and low- (HPA(lo)) responders to ACTH, just before and immediately after ...
The effects of basic fibroblast growth factor (bFGF) on the secretion of PRL and GH by a cell lin... more The effects of basic fibroblast growth factor (bFGF) on the secretion of PRL and GH by a cell line derived from a rat pituitary tumor (GH3 cells) were examined. The interactions between bFGF and compounds that are known to modify the activity of GH3 cells (estradiol, cAMP, and phorbol esters) were also studied. bFGF has little effect on cell growth or on the secretion of GH by GH3 cells but specifically increases the capacity of the cells to release PRL. The effect is time and dose dependent and reaches maximal levels with a 24-h preincubation of the cells with bFGF. The effects of bFGF on PRL secretion are potentiated by the addition of estradiol (maximally effective dose 100 pg/ml approximately 10(-10) M) and are further increased by the addition of the phorbol ester, phorbol myristate acetate. The results indicate that, like in normal lactotrophs, bFGF has a major influence on the release of PRL by tumor-derived GH3 cells. The results support the hypothesis that bFGF may play an important paracrine, if not autocrine, role in regulating the PRL-secreting cells of the pituitary. The potential use of GH3 cells to elucidate the mechanism through which bFGF modulates differentiated cell function is discussed.
Individual variability in the behavioral responsiveness to psychostimulant drugs is due, in part,... more Individual variability in the behavioral responsiveness to psychostimulant drugs is due, in part, to genetic factors. The present study investigated the effects of acute and repeated administrations of cocaine (0, 5, 10 or 20 mg/kg, i.p.) on locomotor activity in male and female rats from genetically distinct strains often used as a model of human childhood hyperactivity/attentional deficit disorder: Wistar Kyoto Hyperactive (WKHA) rats, Spontaneous Hypertensive rats (SHR) and their control Wistar Kyoto (WKY). The results, expressed as percent change in locomotor activity relative to respective control groups, showed that cocaine elicits a dose-dependent hyperactivity in all strains and revealed neither strain nor sex differences in acute sensitivity to moderate doses of the drug. Nevertheless, across repeated administrations, strain and sex differences appeared: WKHA rats displayed a moderate extent of sensitization to psychomotor stimulant effects of cocaine and female rats showed more robust sensitization than males, whatever the strain. These findings support the genotype-dependence in the development of behavioral sensitization to cocaine and confirm the robustness of the sexual dimorphism across different inbred rat strains. Interestingly, the present results demonstrate that sensitization to psychostimulant drugs occurs in genetically hyperactive strains as well as in their normoactive control strain.
... Molecular characterization of fibroblast growth factor. Distribution and biological activitie... more ... Molecular characterization of fibroblast growth factor. Distribution and biological activities in various tissues. BAIRD A. 被引用文献: 1件. 収録刊行物. Rec. Prog. Horm. Res. Rec. Prog. Horm. Res. 42, 143, 1986. 被引用文献: 1件. ...
The present study examined the relationship between ethanol-induced conditioned taste aversion (C... more The present study examined the relationship between ethanol-induced conditioned taste aversion (CTA) and ethanol oral self-administration (OSA) in male and female rats (N = 183) from three related strains not genetically selected for their ethanol preference and differing in their emotional reactivity profile. The strains used were the Wistar Kyoto (WKY), Spontaneously Hypertensive (SHR) and Wistar Kyoto Hyperactive (WKHA). We hypothesized that differences between strains in sensitivity to the aversive properties of alcohol could explain the different propensities to drink alcohol solutions. All animals were given three conditioning trials consisting of 20-minute access to saccharin solution followed by saline or ethanol injections (0.5, 1 or 1.5 g/kg, intraperitoneally). Animals subsequently had free access to ethanol OSA for 3 weeks, followed by two CTA trials. Ethanol injections produce a dose-dependent reduction of saccharin consumption in all animals; moreover, the strength of the CTA is gender- and strain-dependent. Taste avoidance induced by ethanol injections disturbed the initiation of ethanol OSA in two strains (WKY and WKHA) but did not change subsequent long-term ethanol consumption in either strain. In addition, voluntary alcohol drinking experience does not attenuate ethanol-induced CTA, and no association was found between ethanol-induced CTA and ethanol OSA. The data confirm the large variation among strains and between genders in alcohol drinking and taste-aversion learning, but suggest that there is no relationship between the sensitivity to the aversive properties of alcohol and alcohol drinking.
In a previous study using corticosterone treatment of adrenalectomized rats, we hypothesized that... more In a previous study using corticosterone treatment of adrenalectomized rats, we hypothesized that mineralocorticoid receptor (MR)-related mechanisms are constitutively active and that glucocorticoid receptor (GR)-mediated mechanisms are more efficient in Brown Norway rats compared to Fischer 344 (F344) rats. In order to discriminate the mineralocorticoid from the glucocorticoid actions exerted by corticosterone, F344 and Brown Norway adrenalectomized rats were treated with increasing doses (1, 5 and 25 microg/ml of drinking water) of deoxycorticosterone (DOC, MR-specific ligand) or RU 28362 (GR-specific ligand). These rats were compared with long-term adrenalectomized (ADX) untreated rats and sham-ADX rats. This study confirms our previous results, notably the lack of effect of ADX on body weight and fluid intake in Brown Norway rats. Moreover, DOC treatment had no effect in Brown Norway rats whereas the higher dose restored fluid intake of the F344 ADX group to sham values. These results support the hypothesis of a constitutive activation of the MR and therefore the insensitivity of this receptor to its ligand in Brown Norway rats. Alternatively, RU 28362 treatment induced greater weight loss, decrease in food intake, anxiolysis, thymus involution, and decrease in plasma transcortin concentration and pituitary corticosteroid receptor densities in Brown Norway rats than in F344 rats, which is consistent with greater efficiency of GR mechanisms in Brown Norway rats than in F344 rats. Therefore, these strains are of great utility to disentangle MR and GR effects on complex phenotypes.
The hyperlocomotor effect of the serotonin (5-HT)1A,B receptor agonist 5-methoxy-3-(1,2,3,6-tetra... more The hyperlocomotor effect of the serotonin (5-HT)1A,B receptor agonist 5-methoxy-3-(1,2,3,6-tetrahydro-4-pyridinyl)-1H-indole (RU 24969) has been repeatedly reported. However, 5-HT1A receptors, 5-HT1B receptors (or both) have been claimed to mediate this effect of RU 24969. These contradictory data possibly arise from protocol differences, especially those related to animal species, drugs, and activity assessment. Herein, the influence of a pretreatment with the selective 5-HT1B,D receptor antagonist N-[4-methoxy3-(4-methyl-1-piperazinyl)phenyl]-2'-methyl-4'-(5me thyl-1,2,4-oxadiozol-3-yl)-biphenyl-4-carboxamide (GR 127935; 1, 3.3 and 10 mg/kg IP) on the hyperlocomotor effect of a 5 mg/kg (IP) dose of RU 24969 was studied in Wistar-Kyoto Hyperactive (WKHA) rats. In a first series of experiments, it was confirmed that RU 24969 (2.5 and 5 mg/kg), administered 10 min after the onset of activity recordings, increases locomotion dose-dependently (cage crossings). In a second series of experiments, administration of GR 127935 10 min after the onset of activity recordings promoted a dose-dependent decrease in basal activity (and rearings) and prevented (3.3 and 10 mg/kg) RU 24969-elicited locomotor activity. On the other hand, GR 127935 was ineffective against RU 24969-induced inhibition of rearings. Lastly, it was observed that 3.3 mg/kg GR 127935 did not affect the number of cage crossings and rearings displayed by rats administered 1.5 mg/kg D-amphetamine. This study shows that 5-HT1B receptors play a major role in the hyperlocomotor effect of RU 24969, at least under our experimental setting. Whether these receptors also play a tonic role in the high locomotor activity displayed by WKHA rats remains to be determined.
La multiplicité des critères susceptibles d’être utilisés pour évaluer l’adaptation comportementa... more La multiplicité des critères susceptibles d’être utilisés pour évaluer l’adaptation comportementale d’un animal à son environnement a motivé l’étude des relations entre réponses physiologiques et comportementales, dans l’espoir que l’identification de telles relations puisse simplifier l’évaluation du bien-être animal. La comparaison d’animaux placés dans des environnements différents et la comparaison d’animaux aux génotypes extrêmes suggèrent l’existence de relations entre certaines réponses physiologiques et comportementales. La possibilité de catégoriser certains animaux selon leur stratégie de réponse adaptative, caractérisée par des associations répétables entre réponses comportementales et physiologiques, conforte cette hypothèse. Cependant, les relations ainsi suggérées semblent difficilement généralisables : il n’existe pas de relation univoque entre les réponses physiologiques et comportementales d’un animal face à une situation perçue comme menaçante. En l’état actuel des...
We profiled individual differences in alcohol consumption upon initial exposure and during 5 week... more We profiled individual differences in alcohol consumption upon initial exposure and during 5 weeks of voluntary alcohol intake in female mice from 39 BXD recombinant inbred strains and parents using the drinking in the dark (DID) method. In this paradigm, a single bottle of 20% (v/v) alcohol was presented as the sole liquid source for 2 or 4 h starting 3 h into the dark cycle. For 3 consecutive days mice had access to alcohol for 2 h followed by a 4th day of 4 h access and 3 intervening days where alcohol was not offered. We followed this regime for 5 weeks. For most strains, 2 or 4 h alcohol intake increased over the 5-week period, with some strains demonstrating greatly increased intake. There was considerable and heritable genetic variation in alcohol consumption upon initial early and sustained weekly exposure. Two different mapping algorithms were used to identify QTLs associated with alcohol intake and only QTLs detected by both methods were considered further. Multiple sugges...
Stress is a generic term used to describe non-specific responses of the body to all kinds of chal... more Stress is a generic term used to describe non-specific responses of the body to all kinds of challenges. A very large variability in the response can be observed across individuals, depending on numerous conditioning factors like genetics, early influences and life history. As a result, there is a wide range of individual vulnerability and resilience to stress, also called robustness. The importance of robustness-related traits in breeding strategies is increasing progressively towards the production of animals with a high level of production under a wide range of climatic conditions and management systems, together with a lower environmental impact and a high level of animal welfare. The present study aims at describing blood transcriptomic, hormonal, and metabolic responses of pigs to a systemic challenge using lipopolysaccharide (LPS). The objective is to analyze the individual variation of the biological responses in relation to the activity of the HPA axis measured by the level...
Pig husbandry is known as an intensive breeding system, piglets being submitted to multiple stres... more Pig husbandry is known as an intensive breeding system, piglets being submitted to multiple stressful events such as early weaning, successive mixing, crowding and shipping. These stressors are thought to impair immune defences and might contribute, at least partly, to the prophylactic use of antibiotics. Robustness was recently defined as the ability of an individual to express a high-production potential in a wide variety of environmental conditions. Increasing robustness thus appears as a valuable option to improve resilience to stressors and could be obtained by selecting piglets upon their adrenocortical activity. In this study, we aimed at depicting the consequences of an acute social stress on the immune capacity of piglets genetically selected upon divergent hypothalamic-pituitary-adrenocortical (HPA) axis activity. For this purpose, we monitored neuroendocrine and immune parameters, in high- (HPA(hi)) and low- (HPA(lo)) responders to ACTH, just before and immediately after ...
The effects of basic fibroblast growth factor (bFGF) on the secretion of PRL and GH by a cell lin... more The effects of basic fibroblast growth factor (bFGF) on the secretion of PRL and GH by a cell line derived from a rat pituitary tumor (GH3 cells) were examined. The interactions between bFGF and compounds that are known to modify the activity of GH3 cells (estradiol, cAMP, and phorbol esters) were also studied. bFGF has little effect on cell growth or on the secretion of GH by GH3 cells but specifically increases the capacity of the cells to release PRL. The effect is time and dose dependent and reaches maximal levels with a 24-h preincubation of the cells with bFGF. The effects of bFGF on PRL secretion are potentiated by the addition of estradiol (maximally effective dose 100 pg/ml approximately 10(-10) M) and are further increased by the addition of the phorbol ester, phorbol myristate acetate. The results indicate that, like in normal lactotrophs, bFGF has a major influence on the release of PRL by tumor-derived GH3 cells. The results support the hypothesis that bFGF may play an important paracrine, if not autocrine, role in regulating the PRL-secreting cells of the pituitary. The potential use of GH3 cells to elucidate the mechanism through which bFGF modulates differentiated cell function is discussed.
Individual variability in the behavioral responsiveness to psychostimulant drugs is due, in part,... more Individual variability in the behavioral responsiveness to psychostimulant drugs is due, in part, to genetic factors. The present study investigated the effects of acute and repeated administrations of cocaine (0, 5, 10 or 20 mg/kg, i.p.) on locomotor activity in male and female rats from genetically distinct strains often used as a model of human childhood hyperactivity/attentional deficit disorder: Wistar Kyoto Hyperactive (WKHA) rats, Spontaneous Hypertensive rats (SHR) and their control Wistar Kyoto (WKY). The results, expressed as percent change in locomotor activity relative to respective control groups, showed that cocaine elicits a dose-dependent hyperactivity in all strains and revealed neither strain nor sex differences in acute sensitivity to moderate doses of the drug. Nevertheless, across repeated administrations, strain and sex differences appeared: WKHA rats displayed a moderate extent of sensitization to psychomotor stimulant effects of cocaine and female rats showed more robust sensitization than males, whatever the strain. These findings support the genotype-dependence in the development of behavioral sensitization to cocaine and confirm the robustness of the sexual dimorphism across different inbred rat strains. Interestingly, the present results demonstrate that sensitization to psychostimulant drugs occurs in genetically hyperactive strains as well as in their normoactive control strain.
... Molecular characterization of fibroblast growth factor. Distribution and biological activitie... more ... Molecular characterization of fibroblast growth factor. Distribution and biological activities in various tissues. BAIRD A. 被引用文献: 1件. 収録刊行物. Rec. Prog. Horm. Res. Rec. Prog. Horm. Res. 42, 143, 1986. 被引用文献: 1件. ...
The present study examined the relationship between ethanol-induced conditioned taste aversion (C... more The present study examined the relationship between ethanol-induced conditioned taste aversion (CTA) and ethanol oral self-administration (OSA) in male and female rats (N = 183) from three related strains not genetically selected for their ethanol preference and differing in their emotional reactivity profile. The strains used were the Wistar Kyoto (WKY), Spontaneously Hypertensive (SHR) and Wistar Kyoto Hyperactive (WKHA). We hypothesized that differences between strains in sensitivity to the aversive properties of alcohol could explain the different propensities to drink alcohol solutions. All animals were given three conditioning trials consisting of 20-minute access to saccharin solution followed by saline or ethanol injections (0.5, 1 or 1.5 g/kg, intraperitoneally). Animals subsequently had free access to ethanol OSA for 3 weeks, followed by two CTA trials. Ethanol injections produce a dose-dependent reduction of saccharin consumption in all animals; moreover, the strength of the CTA is gender- and strain-dependent. Taste avoidance induced by ethanol injections disturbed the initiation of ethanol OSA in two strains (WKY and WKHA) but did not change subsequent long-term ethanol consumption in either strain. In addition, voluntary alcohol drinking experience does not attenuate ethanol-induced CTA, and no association was found between ethanol-induced CTA and ethanol OSA. The data confirm the large variation among strains and between genders in alcohol drinking and taste-aversion learning, but suggest that there is no relationship between the sensitivity to the aversive properties of alcohol and alcohol drinking.
In a previous study using corticosterone treatment of adrenalectomized rats, we hypothesized that... more In a previous study using corticosterone treatment of adrenalectomized rats, we hypothesized that mineralocorticoid receptor (MR)-related mechanisms are constitutively active and that glucocorticoid receptor (GR)-mediated mechanisms are more efficient in Brown Norway rats compared to Fischer 344 (F344) rats. In order to discriminate the mineralocorticoid from the glucocorticoid actions exerted by corticosterone, F344 and Brown Norway adrenalectomized rats were treated with increasing doses (1, 5 and 25 microg/ml of drinking water) of deoxycorticosterone (DOC, MR-specific ligand) or RU 28362 (GR-specific ligand). These rats were compared with long-term adrenalectomized (ADX) untreated rats and sham-ADX rats. This study confirms our previous results, notably the lack of effect of ADX on body weight and fluid intake in Brown Norway rats. Moreover, DOC treatment had no effect in Brown Norway rats whereas the higher dose restored fluid intake of the F344 ADX group to sham values. These results support the hypothesis of a constitutive activation of the MR and therefore the insensitivity of this receptor to its ligand in Brown Norway rats. Alternatively, RU 28362 treatment induced greater weight loss, decrease in food intake, anxiolysis, thymus involution, and decrease in plasma transcortin concentration and pituitary corticosteroid receptor densities in Brown Norway rats than in F344 rats, which is consistent with greater efficiency of GR mechanisms in Brown Norway rats than in F344 rats. Therefore, these strains are of great utility to disentangle MR and GR effects on complex phenotypes.
The hyperlocomotor effect of the serotonin (5-HT)1A,B receptor agonist 5-methoxy-3-(1,2,3,6-tetra... more The hyperlocomotor effect of the serotonin (5-HT)1A,B receptor agonist 5-methoxy-3-(1,2,3,6-tetrahydro-4-pyridinyl)-1H-indole (RU 24969) has been repeatedly reported. However, 5-HT1A receptors, 5-HT1B receptors (or both) have been claimed to mediate this effect of RU 24969. These contradictory data possibly arise from protocol differences, especially those related to animal species, drugs, and activity assessment. Herein, the influence of a pretreatment with the selective 5-HT1B,D receptor antagonist N-[4-methoxy3-(4-methyl-1-piperazinyl)phenyl]-2'-methyl-4'-(5me thyl-1,2,4-oxadiozol-3-yl)-biphenyl-4-carboxamide (GR 127935; 1, 3.3 and 10 mg/kg IP) on the hyperlocomotor effect of a 5 mg/kg (IP) dose of RU 24969 was studied in Wistar-Kyoto Hyperactive (WKHA) rats. In a first series of experiments, it was confirmed that RU 24969 (2.5 and 5 mg/kg), administered 10 min after the onset of activity recordings, increases locomotion dose-dependently (cage crossings). In a second series of experiments, administration of GR 127935 10 min after the onset of activity recordings promoted a dose-dependent decrease in basal activity (and rearings) and prevented (3.3 and 10 mg/kg) RU 24969-elicited locomotor activity. On the other hand, GR 127935 was ineffective against RU 24969-induced inhibition of rearings. Lastly, it was observed that 3.3 mg/kg GR 127935 did not affect the number of cage crossings and rearings displayed by rats administered 1.5 mg/kg D-amphetamine. This study shows that 5-HT1B receptors play a major role in the hyperlocomotor effect of RU 24969, at least under our experimental setting. Whether these receptors also play a tonic role in the high locomotor activity displayed by WKHA rats remains to be determined.
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