@article{APS7403,
author = {Hong Qian and Li-Ping Yang and Zhen-Yu Wei and Ai-Dong Liu and Hong Tian and Su-Fen Yang},
title = {Central norepinephrine pathways are involved in cardiovascular response to intracerebroventricular substance P},
journal = {Acta Pharmacologica Sinica},
volume = {22},
number = {4},
year = {2016},
keywords = {},
abstract = {Aim: To study the role of norepinephrine system in the cardiovascular response to intracerebroventricular substance P (SP) in rabbit.
Methods: SP was given intracerebroventricularly in anesthetized rabbits pretreated with the catecholaminergic neurotoxin, 6-hydroxydopamine (6-OHDA). The density and affinity of SP receptors on synaptosomal membranes of the hypothalamus and the ventral medulla of rabbits were determined by [125I]SP receptor assay. Arterial blood pressure and heart rate were recorded.
Results: Intracerebroventricular (icv) pretreatment of rabbits with 6-OHDA, reduced norepinephrine in the hypothalamus (by 86.7 %) and in the ventral medulla (by 77.0 %) respectively. The pressor response and tachycardia of these rabbits to icv SP (3.55 nmol . kg-1) were attenuated. The density and the affinity of SP receptors in the hypothalamus and the ventral medulla of 6-OHDA-lesioned rabbits were decreased. The Bmax (pmol . g-1 protein) of SP receptors in hypothalamus and the ventral medulla are 108 +/- 5, 35.9 +/- 2.2 in control group, and 42 +/- 18, 20 +/- 5 in 6-OHDA-lesioned rabbits, respectively. Kd (nmol . L-1) of SP receptors in the two regions are 0.015 +/- 0.004, 0.014 +/- 0.006 in control group and 0.029 +/- 0.001, 0.015 +/- 0.003 in 6-OHDA group. There is a significant difference of Bmax (P < 0.01) and Kd (P < 0.01, P < 0.05) in both regions between 6-OHDA groups and control groups.
Conclusion: The results suggested that central norepinephrine pathways are involved in the cardiovascular response to icv SP.},
issn = {1745-7254}, url = {http://www.chinaphar.com/article/view/7403}
}