Cardiovascular instability induced by intracerebroventricular administration of vasopressin or corticotrophin-releasing factor in conscious long evans and brattleboro rats.
Abstract Conscious Long Evans and Brattleboro rats, chronically instrumented with pulsed Doppler probes around left renal and superior mesenteric arteries and the distal abdominal aorta, had vasopressin or corticotrophin-releasing factor administered intracerebroventricularly. In Long Evans rats, vasopressin caused no cardiovascular instability, but in Brattleboro rats, vasopressin caused the development of marked oscillations in blood pressure and heart rate. Under the latter conditions, falls in blood pressure were accompanied by increases in hindquarter blood flow. Similar oscillations in blood pressure, heart rate and regional haemodynamics were seen in Long Evans and Brattleboro rats given corticotrophin-releasing factor. These results indicate that centrally-administered vasopressin and corticotrophin-releasing factor can have an important influence on the control of regional haemodynamics. In some respects the effects of the peptides resemble the changes seen during the defence reaction.
Gardiner
S M
SM
Department of Physiology and Pharmacology, Medical School, Queen's Medical Centre, Nottingham NG7 2UH, UK.
Compton
A M
AM
Bennett
T
T