Date of Award

8-10-2005

Degree Type

Dissertation

Degree Name

Ph.D.

Degree Program

Psychology

Department

Psychology

Major Professor

King, Bruce

Second Advisor

Vaccarino, Anthony

Third Advisor

LaHoste, Gerald

Fourth Advisor

Howard, Jerome

Fifth Advisor

Daniel, Jill

Abstract

Previous research has demonstrated body weight gain in rats after lesions to the posterodorsal amygdala. Likewise, a recent study also found increased body weight as a result of knife-cuts of the stria terminalis, just as it exits the amygdala. In the present study, these findings were extended and previous studies replicated by producing 1) lesions in the stria terminalis as it travels dorsally through the brain, 2) coronal knife-cuts anterior to the ventromedial hypothalamus, and 3) axon-sparing lesions of the posterodorsal amygdala using ibotenic acid. Both lesions of the dorsal stria terminalis and coronal knife-cuts anterior to the ventromedial hypothalamus resulted in significant weight gain in female rats as compared to controls. The failure of previous research to find effects after these treatments is attributed to the use of male animals. In addition, examination of anterograde degeneration using an amino-cupric-silver stain in two rats with knife-cuts revealed degenerating terminals in the shell of the VMH and the premammillary nuclei, indicating that the dorsal component of the stria terminalis had been severed. The results of ibotenic acid lesions of the posterodorsal amygdala are unable to be reported due to the inability to histologically verify the lesions. This may have been cause by acid seepage into the lateral ventricles. While the amygdala can not be confirmed as the origin of information concerning body weight regulation and food intake, the stria terminalis does seem to carry this information, exerting an inhibitory influence on the ventromedial hypothalamus.

Rights

The University of New Orleans and its agents retain the non-exclusive license to archive and make accessible this dissertation or thesis in whole or in part in all forms of media, now or hereafter known. The author retains all other ownership rights to the copyright of the thesis or dissertation.

Share

COinS