|
|
||||||||
AJP - Regulatory, Integrative and Comparative Physiology, Vol 252, Issue 5 947-R952, Copyright © 1987 by American Physiological Society
ARTICLES |
J. H. Jhamandas and L. P. Renaud
The excitability of vasopressin-secreting neurons in the hypothalamic supraoptic nucleus is transiently depressed by an abrupt increase in arterial pressure sufficient to activate peripheral arterial baroreceptors. The present experiments examined the ability of locally applied transmitter antagonists to alter this response. Extracellular data were obtained from 27 supraoptic vasopressin-secreting neurons in pentobarbital-anesthetized male Long-Evans rats. In seven of eight cells tested, bicuculline (100 microM) reversibly abolished or delayed the anticipated cessation in neuronal firing that accompanied a 40- to 60-mmHg increase in arterial pressure induced by a brief intravenous infusion of the alpha-agonist metaraminol. Similar tests applied to the remaining cells revealed that prazosin (10 microM), timolol (20 microM), or strychnine (100 microM) were ineffective. These findings suggest that gamma-aminobutyric acidA receptors mediate the depressant responses observed among supraoptic vasopressin-secreting neurons consequent to peripheral baroreceptor activation.
This article has been cited by other articles:
![]() |
R. R. Grindstaff and J. T. Cunningham Lesion of the perinuclear zone attenuates cardiac sensitivity of vasopressinergic supraoptic neurons Am J Physiol Regulatory Integrative Comp Physiol, March 1, 2001; 280(3): R630 - R638. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |