Forebrain regions affected by lateral parabrachial nucleus serotonergic mechanisms that influence sodium appetite

Abstract

Blockade of serotonergic receptors in the lateral parabrachial nucleus (LPBN), via bilateral injections of nonselective 5-hydroxytryptamine (5-HT)1/2-receptor antagonist, methysergide causes a robust sodium appetite. Our aim was to elucidate which brain regions are activated when serotonergic pathways to the LPBN are blocked and combined with subcutaneous injection of isoproterenol causing a salt appetite. In the experimental group, conscious rats were administered methysergide (4 μg/0.2 μl) injected bilaterally into the LPBN. Control groups included rats administered with injections of vehicle bilaterally into the LPBN, rats administered methysergide into injection sites outside the LPB reg..