Central noradrenergic pathways are not involved in the pressor response to intracerebroventricular substance P.
Intracerebroventricular (i.c.v.) pretreatment of Wistar rats with the catecholaminergic neurotoxin, 6-hydroxydopamine, significantly reduced noradrenaline in the pons/medulla (by 73%) and almost abolished the noradrenaline levels in the spinal cord (by 89%). The pressor response of these animals to i.c.v. angiotensin II (ANGII, 10 ng) was significantly attenuated. In contrast, there was no significant effect on the pressor response to i.c.v. substance P (SP, 100 ng). The results provide evidence that different central pathways mediate the pressor response to ANGII and SP.
Badoer
E
E
Department of Pharmacology, German Institute for High Blood Pressure Research, University of Heidelberg.
Würth
H
H
Qadri
F
F
Itoi
K
K
Unger
T
T
D000804:Angiotensin II / Q000494:pharmacology; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D001921:Brain / Q000502:physiology*; D006339:Heart Rate / Q000187:drug effects; D007276:Injections, Intraventricular; D008297:Male; D009638:Norepinephrine / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains; D013373:Substance P / Q000494:pharmacology*
D000804:Angiotensin II; D013373:Substance P; D009638:Norepinephrine