SEPTO-HYPOTHALAMIC ORGANIZATION OF A STEREOTYPED BEHAVIOR CONTROLLED BY VASOPRESSIN IN GOLDEN-HAMSTERS

In golden hamsters, microinjections of arginine vasopressin (AW) withi n the anterior hypothalamus (AH) and lateral septum (LS) elicit the di splay of a stereotyped behavior: flank marking. As these areas are rec iprocally connected, we tested whether AW-sensitive sites constitute a n organized network. Flank marking was recorded in animals with iboten ic acid lesions within the AH or LS after AVP injections within the LS or AH. While AVP injections in the AH and LS induced high flank-marki ng scores, certain lesions blocked the behavior. Lesions of the LS fai led to affect flank marking induced by injections within the AH. In co ntrast, unilateral AH lesions blocked flank marking induced either by LS injections or AH injections in the contralateral side. These result s suggest that the bilateral integrity of the AH is critical for the a ctivation of flank-marking behavior by AVP. Together, these data sugge st that the AH is an important relay of the neural network controlling flank-marking behavior.