Central cardiovascular effects induced by intracisternal pacap in dogs.
Seki, Yukio, Yoshio Suzuki, Mustafa K. Baskaya, Kiyoshi Saito, Masakazu
Takayasu, Masato Shibuya, and Kenichiro Sugita.
Department of Neurosurgery, Nagoya University School of Medicine, Nagoya
466, Japan, Present address: Department of Neurosurgery, Ankara University
School of Medicine, Ibni Sina Hospital, Ankara, Turkey
APStracts 2:0014H, 1995.
The cardiovascular responses to intracisternally administered pituitary
adenylate cyclase-activating polypeptide (PACAP) were investigated and
compared to those of vasoactive intestinal peptide (VIP) in anesthetized
dogs. Intracisternal administration of 10 nmol of PACAP27 increased mean
arterial blood pressure (MABP) significantly with simultaneous increase of
plasma arginine vasopressin and adrenaline concentrations. Intracisternal
administration of VIP increased plasma arginine vasopressin concentration
significantly but caused no appreciable change in MABP. Systemic infusion of
the non-peptide vasopressin V1 receptor antagonist, OPC-21268, did not
inhibit the PACAP27-induced increase in MABP, while phentolamine, an [alpha]
adrenoceptor blocker, reversed the increase. Intracisternal pretreatment with
the vasopressin V1 receptor antagonist, [Pmp1, Tyr(Me)2]-Arg8
-vasopressin, also inhibited the increase. All of these findings suggest that
PACAP has a central pressor action by increasing sympathetic outflow, which
is probably mediated by the vasopressinergic neural network. PACAP seems to
play important roles in hormonal and neural control of systemic circulation.
Received 3 August 1994; accepted in final form 19 January 1995.
APS Manuscript Number H696-4.
Article publication pending Am. J. Physiol. (Heart Circ. Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 24 February 1995.