AJP - Regulatory, Integrative and Comparative Physiology, Vol 250, Issue 4 567-R572, Copyright © 1986 by American Physiological Society
Enhanced noradrenergic activity in kidney of Brattleboro rats with diabetes insipidus
R. L. Kline, K. P. Patel and P. F. Mercer
The possibility that sympathetic nervous system activity may be altered in
Brattleboro rats with diabetes insipidus (DI) was studied using the
norepinephrine (NE) turnover technique. Female DI and Long-Evans rats were
used. NE turnover in peripheral organs was calculated by measuring the
decline in tissue [NE] after inhibition of tyrosine hydroxylase with
alpha-methyltyrosine. NE turnover was increased significantly in the kidney
of DI rats but was not significantly altered in other peripheral organs
examined (heart, duodenum, skeletal muscle). Both NE and epinephrine
concentrations in the adrenal gland were significantly higher in the DI
rats. Treatment of DI rats for 7 days with vasopressin tannate (Pitressin,
100 mU/100 g) or 1-deamino-[8-D-arginine] vasopressin (DDAVP, 250 ng X kg-1
X day-1) reversed the changes in renal NE turnover and also decreased the
turnover in other tissues. The results of these studies suggest that,
compared with Long-Evans rats, DI rats have a selective increase in NE
turnover in the kidney and the potential to release more catecholamines
from the adrenal glands. The apparently nonspecific effect of antidiuretic
therapy on NE turnover in DI rats is probably mediated by the epithelial
receptor for vasopressin, because both Pitressin and DDAVP produced similar
results.
