Faculty Articles

Publication Title

Neurochemical Research

Publisher

Springer Nature

ISSN

0364-3190

Publication Date

10-1-2015

Keywords

AT1 angiotensin, C1 adrenergic neurons, RVLM, Radioligand binding, Rat brain, Receptor autoradiography, Receptors, Rostral ventrolateral medulla

Abstract

Cardiovascular homeostasis is regulated in large part by the rostral ventrolateral medulla (RVLM) in mammals. Projections from the RVLM to the intermediolateral column of the thoracolumbar spinal cord innervate preganglionic neurons of the sympathetic nervous system causing elevation of blood pressure and heart rate. A large proportion, but not all, of the neurons in the RVLM contain the enzymes necessary for the production of epinephrine and are identified as the C1 cell group. Angiotensin II (Ang II) activates the RVLM acting upon AT1 receptors. To assess the proportion of AT1 receptors that are located on C1 neurons in the rat RVLM this study employed an antibody to dopamine-beta-hydroxylase conjugated to saporin, to selectively destroy C1 neurons in the RVLM. Expression of tyrosine hydroxylase immunoreactive neurons in the RVLM was reduced by 57 % in the toxin injected RVLM compared to the contralateral RVLM. In contrast, densitometric analysis of autoradiographic images of (125)I-sarcosine(1), isoleucine(8) Ang II binding to AT1 receptors of the injected side RVLM revealed a small (10 %) reduction in AT1-receptor expression compared to the contralateral RVLM. These results suggest that the majority of AT1 receptors in the rat RVLM are located on non-C1 neurons or glia.

DOI

10.1007/s11064-015-1649-3

Volume

40

Issue

10

First Page

2113

Last Page

2120

Disciplines

Medicine and Health Sciences | Pharmacy and Pharmaceutical Sciences

Rights

Springer Science+Business Media New York 2015

Peer Reviewed

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