Lesions of the central nucleus of the amygdala. I: Effects on taste reactivity, taste aversion learning and sodium appetite.
Bilateral damage to the central nucleus of the amygdala (CeAX) in the rat blunts need-induced NaCl intake and abolishes daily need-free NaCl intake when measured with a two-bottle test. Such a deficit could be the result of impaired taste function. To assess the taste function of the CeAX rat various taste stimuli were introduced directly into the oral cavity and taste-elicited oral motor responses were measured. Oral motor responses elicited by 0.62 M and 0.13 M sodium chloride, 0.3 M sucrose and 0.01 M citric acid, were similar in control and CeAX rats. Additionally CeAX and control rats acquired a taste aversion for fructose or maltose when either was paired with LiCl. Finally, in CeAX rats, like in control rats, the pattern of oral motor responses to 0.5 M NaCl was dependent on internal state; sodium depletion dramatically altered taste-elicited oral motor behavior. These results suggest that, in the rat, the deficits in NaCl intake behavior that follow CeAX do not appear to be a result of dramatic changes in gustatory function.
Galaverna
O G
OG
Department of Biology, University of Pennsylvania, Philadelphia.
Seeley
R J
RJ
Berridge
K C
KC
Grill
H J
HJ
Epstein
A N
AN
Schulkin
J
J
D000679:Amygdala / Q000033:anatomy & histology / Q000502:physiology*; D000818:Animals; D001066:Appetite / Q000187:drug effects*; D001362:Avoidance Learning / Q000502:physiology*; D018021:Lithium Chloride / Q000494:pharmacology; D008297:Male; D009055:Mouth / Q000502:physiology; D009068:Movement / Q000502:physiology; D009434:Neural Pathways / Q000502:physiology; D011149:Pons / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012982:Sodium, Dietary / Q000494:pharmacology*; D013649:Taste / Q000502:physiology*
D012982:Sodium, Dietary; D018021:Lithium Chloride