Central cardiovascular effects induced by intracisternal PACAP in dogs.
The cardiovascular responses to intracisternally administered pituitary adenylate cyclase-activating polypeptide (PACAP) were investigated and compared with those of vasoactive intestinal peptide (VIP) in anesthetized dogs. Intracisternal administration of 10 nmol of PACAP-27 increased mean arterial blood pressure (MABP) significantly with a simultaneous increase of plasma arginine vasopressin and epinephrine concentrations. Intracisternal administration of VIP increased plasma arginine vasopressin concentration significantly but caused no appreciable change in MABP. Systemic infusion of the nonpeptide vasopressin V1 receptor antagonist OPC-21268 did not inhibit the PACAP-27-induced increase in MABP, whereas 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. 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.
Seki
Y
Y
Department of Neurosurgery, Nagoya University School of Medicine, Japan.
Suzuki
Y
Y
Baskaya
M K
MK
Saito
K
K
Takayasu
M
M
Shibuya
M
M
Sugita
K
K
D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology; D000818:Animals; D065092:Antidiuretic Hormone Receptor Antagonists; D001127:Arginine Vasopressin / Q000097:blood; D001794:Blood Pressure / Q000187:drug effects; D001921:Brain / Q000502:physiology*; D002319:Cardiovascular System / Q000187:drug effects*; D002395:Catecholamines / Q000097:blood; D002946:Cisterna Magna; D004285:Dogs; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D007267:Injections; D008297:Male; D009479:Neuropeptides / Q000494:pharmacology*; D018377:Neurotransmitter Agents / Q000494:pharmacology; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D014660:Vasoactive Intestinal Peptide / Q000494:pharmacology
D000317:Adrenergic alpha-Antagonists; D065092:Antidiuretic Hormone Receptor Antagonists; D002395:Catecholamines; D009479:Neuropeptides; D018377:Neurotransmitter Agents; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D001127:Arginine Vasopressin; D014660:Vasoactive Intestinal Peptide