TY - JOUR
T1 - Evidence for a specific role of vasopressin in sustaining pituitary-adrenocortical stress response in the rat
AU - Scaccianoce, Sergio
AU - Muscolo, Luisa A A
AU - Cigliana, Giovanni
AU - Navarra, Domitilla
AU - Nicolai, Raffaella
AU - Angelucci, Luciano
PY - 1991/6
Y1 - 1991/6
N2 - In the adult male Wistar rat a 2-fold 2-min restraint stress exposure, repeated 15 min apart, activated the adrenocortical secretion more than a single one would have. However, in rats with a pharmacological block of the endogenous CRF release, exogenous CRH (0.3 μg/kg iv), administered 15 min after a first similar dose, was unable to stimulate pituitary-adrenocortical activity above the level attained with the first peptide injection. On the contrary, in the same conditions exogenous arginine vasopressin (AVP) (0.3 μg/kg iv) administered 15 min after CRH, was able to further stimulate pituitary-adrenocortical activity. Using the same experimental procedure, oxytocin (0.3 μg/kg iv) was found to be totally inactive. The physiological import of these findings was investigated in the Brattleboro rat, genetically lacking in endogenous AVP, in which, unlike the control Long-Evans strain, the 2-fold stress exposure did not cause an increase in plasma corticosterone concentration greater than that of a single exposure. These results suggest that endogenous AVP is essential in sustaining adrenocortical activation in circumstances in which pituitary refractoriness towards CRH stimulation intervenes.
AB - In the adult male Wistar rat a 2-fold 2-min restraint stress exposure, repeated 15 min apart, activated the adrenocortical secretion more than a single one would have. However, in rats with a pharmacological block of the endogenous CRF release, exogenous CRH (0.3 μg/kg iv), administered 15 min after a first similar dose, was unable to stimulate pituitary-adrenocortical activity above the level attained with the first peptide injection. On the contrary, in the same conditions exogenous arginine vasopressin (AVP) (0.3 μg/kg iv) administered 15 min after CRH, was able to further stimulate pituitary-adrenocortical activity. Using the same experimental procedure, oxytocin (0.3 μg/kg iv) was found to be totally inactive. The physiological import of these findings was investigated in the Brattleboro rat, genetically lacking in endogenous AVP, in which, unlike the control Long-Evans strain, the 2-fold stress exposure did not cause an increase in plasma corticosterone concentration greater than that of a single exposure. These results suggest that endogenous AVP is essential in sustaining adrenocortical activation in circumstances in which pituitary refractoriness towards CRH stimulation intervenes.
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M3 - Article
C2 - 2036982
AN - SCOPUS:0025775936
VL - 128
SP - 3138
EP - 3143
JO - Endocrinology
JF - Endocrinology
SN - 0013-7227
IS - 6
ER -