Summary
Plasma concentration, metabolic clearance rate and in vitro adrenal production of corticosterone were measured in Brattleboro male rats homozygous
for diabetes insipidus (DI) and in Long-Evans male rats (LE) as controls in resting
conditions, under stress caused by pentobarbitone anesthesia and surgery and after
three days water deprivation.
In resting animals, plasma concentrations and in vitro adrenal production of corticosterone were higher in DI rats than in LE rats.
Under pentobarbitone anesthesia and surgery, plasma concentrations and metabolic clearance
rate of corticosterone were slightly but not statistically lower in DI rats; however,
the in vivo production rate of corticosterone was significantly lower.
After three days water deprivation, increasing plasma corticosterone level was consistently
higher in DI than in LE rats.
These results are not in favour of a reduced glucocorticoid activity of the adrenal
of DI rats and of an important role played by vasopressin on the stimulation of the
hypothalamopituitary adrenal activity at least in resting conditions; its role may
depend upon stressful circumstances.
Key-Words:
Brattleboro Rats
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Vasopressin
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Corticosterone
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Metabolic Clearance Rate
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Water Deprivation
