Centrifugal Modulation in the Vertebrate Olfactory Epithelium

Michigan State University, East Lansing MI

Investigators

Abstract

Heather L. Eisthen 0817785 Centrifugal Modulation in the Vertebrate Olfactory Epithelium The brain sends signals to the sense organs to focus attention on the stimuli that are most important at any given time, depending on the animal's behavioral context or physiological state. Although this type of activity has been described in the eye and ear, it has received little attention in the nose, or olfactory organ. Research by Dr. Eisthen and her collaborators suggests that the terminal nerve, a nerve that extends between the brain and nose, releases chemicals into the olfactory organ that change its activity. Specifically, the terminal nerve contains two chemicals, gonadotropin releasing hormone (GnRH) and neuropeptide Y (NPY), that change odorant responses and excitability of olfactory neurons in the nose. The effects appear to depend on the animal's overall physiological condition: GnRH is more likely to affect olfactory receptor neurons during the breeding season, and NPY?s effects are limited to hungry animals. This is interesting, because in other parts of the brain, GnRH functions to control release of hormones involved in reproduction, whereas NPY is involved in controlling appetite and hunger. The project will involve a combination of anatomical, electrophysiological, molecular, and biochemical techniques, and are expected to reveal how specific these effects are, as well as the cellular and molecular changes that underlie these effects. The research will contribute to the training of students and researchers at Michigan State University, and involves cooperation with scientists in other parts of the United States as well as in Japan and Sweden.