AJP - Regulatory, Integrative and Comparative Physiology, Vol 252, Issue 1 102-R108, Copyright © 1987 by American Physiological Society
Abnormal blood pressure recovery during ganglion blockade in diabetic rats
R. A. Hebden, T. Bennett and S. M. Gardiner
The aim of the present study was to determine the extent to which
vasopressin or the renin-angiotensin system contributed to the recovery of
blood pressure following acute hypotension induced by treatment with
pentolinium and captopril, or pentolinium and the vasopressin antagonist
d(CH2)5DAVP, respectively, in conscious, free-moving rats treated 21 days
previously with saline or streptozotocin (STZ) (60 mg/kg ip). Half the
animals given STZ were subsequently treated with insulin (about 4.5 U/day).
The STZ-treated animals demonstrated a resting bradycardia and systolic
hypotension. The vasopressin-mediated recovery in blood pressure seen
following administration of pentolinium, in the presence of captopril, and
the renin-angiotensin-mediated recovery seen following administration of
pentolinium, in the presence of d(CH2)5DAVP, were both found to be
significantly (P less than 0.05) attenuated in the STZ-treated animals.
These abnormalities were absent in the animals injected with STZ and
treated daily with insulin, but receiving their last dose 24 h before
measurement. At that time the animals had elevated blood glucoses. These
results indicate that the abnormalities observed were not due to toxic
effects of STZ or to hyperglycemia per se.
