5-HT receptor blockade in the posterior amygdala elicits feeding in female rats.
Previous work suggests that feeding following intraventricular (i.v.t.) injections of the serotonin (5-HT)(1/2/7) antagonist metergoline (MET) is not localized to the hypothalamus. Since lesions of the posterior basolateral amygdala (pBLA) block feeding following systemic 5-HT1A agonist 8-hydroxy-2(di-n-propylamino)tetralin, the ability of intra-pBLA MET to elicit feeding was investigated. In two separate experiments, feeding of female rats was measured over 2 h following 0, 3, 10 and 30 nmol and 0, 0.03, 0.3 and 3 nmol MET (mol. wt. 403.5) injected bilaterally into each pBLA. All three doses used in Experiment 1 increased feeding over 2 h. In Experiment 2, feeding over the first hour was enhanced after the two highest doses. Since intra-pBLA MET elicits feeding comparable to that seen using much higher doses administered i.v.t. these data implicate the pBLA as an extra-hypothalamic site mediating the effects of 5-HT in feeding control.
Parker
G C
GC
Department of Psychology, College of Science, School of Medicine, Wayne State University, MI 48202, USA.
Balboul
R
R
Hobday
J A
JA
Coscina
D V
DV
D000679:Amygdala / Q000033:anatomy & histology / Q000187:drug effects*; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D005247:Feeding Behavior / Q000187:drug effects*; D005260:Female; D007276:Injections, Intraventricular; D008711:Metergoline / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D011985:Receptors, Serotonin / Q000187:drug effects*; D012702:Serotonin Antagonists / Q000494:pharmacology*
D011985:Receptors, Serotonin; D012702:Serotonin Antagonists; D008711:Metergoline