Effect of Neuropeptide Y on Alpha 2-adrenoceptor-mediated Cardiovascular Responses in the Pithed Rat

Overview

Journal Br J Pharmacol

Publisher Wiley

Specialty Pharmacology

Date 1990 Aug 1

PMID 2169943

Citations 1

Authors

E Vila

I M Macrae

Affiliations

Soon will be listed here.

Abstract

1. The effects of neuropeptide Y (NPY) on the cardiovascular responses induced by stimulation of pre and postjunctional alpha 2-adrenoceptors were studied in the pithed normotensive rat. 2. The increase in diastolic blood pressure induced by cumulative injection of xylazine (1-1000 micrograms kg-1, i.v.) were potentiated by NPY (5 micrograms kg-1) but not affected by a lower dose (0.75 micrograms kg-1) of this peptide. 3. Xylazine (1-100 micrograms kg-1) inhibited in a dose-dependent manner the tachycardia induced by continuous electrical stimulation (0.2 Hz, 2 ms, 60 V) of the spinal cord (C7-Thl). 4. NPY (5 micrograms kg-1 but not 0.75 micrograms kg-1) enhanced the inhibitory effect of xylazine on the tachycardia induced by electrical stimulation without having any direct effect on heart rate. 5. These results suggest that there may be a positive interaction between NPY receptors, postjunctional alpha 2-adrenoceptors and between NPY receptors and postjunctional alpha 2-adrenoceptors in the cardiovascular system of the rat.

Citing Articles

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PMID: 1682818 DOI: 10.1007/BF00184294.

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