ROLE OF THE CENTRAL NUCLEUS OF THE AMYGDALA AND BED NUCLEUS OF THE STRIA TERMINALIS IN EXPERIMENTALLY-INDUCED SALT APPETITE

The contributions of the central nucleus of the amygdala (CeA) and the bed nucleus of the stria terminalis (BST) to salt appetite were evalu ated with two treatments which induce sodium chloride (NaCl) ingestion . Cumulative 3 h intakes of 2% NaCl after sodium depletion using furos emide, or subcutaneous (s.c.) injections of yohimbine (YOH), were meas ured in male, Sprague-Dawley rats both before and after electrolytic l esions of the CeA or the BST. Before surgery, sham-lesion and lesion g roups drank equivalent amounts of 2% NaCl in response to furosemide de pletion and YOH treatment. After surgery, rats with sham lesions incre ased their intakes of 2% NaCl following YOH while rats with CeA or BST lesions showed significant decreases. Rats with CeA or BST lesions al so showed significant decreases in their intake of 2% NaCl after furos emide depletion, while intakes of the sham lesion groups remained unch anged. Lesions of either nucleus virtually eliminated 24 h need-free s alt intake. Before and after surgery, all groups drank equivalent amou nts of water in response to s.c. angiotensin II and to s.c. hypertonic saline, indicating the lesions specifically affected salt appetite. T he results indicate that the CeA and the BST may be important sites fo r processing inputs mediating salt appetite.