9808428 Murray Gap junctions between adrenal gland cells may provide a passageway for movement of regulatory molecules involved in adrenal function. Dr. Murray will test the hypothesis that gap junctions between adjacent adrenal cells participate in adrenal gland function and that gap junction expression is dependent on the functional state of the adrenal gland. Mice will be treated with compounds and/or procedures known to influence adrenal cell proliferation, steroidogenesis and morphology. Specifically, the effect of adrenocorticotropin (ACTH), dexamethasone, low sodium diet, hypophysectomy and adrenal regeneration on gap junctions will be studied in vivo (Objective 1). Adrenal glands from each of these treatment groups will be harvested for further study in cell culture (Objective 2). Transgeneic (lack Cx43 gap junction protein) mouse adrenal glands will e transplanted into adult mice. Adrenal gland viability, growth, steroidogenesis and cell proliferation will be measured in the adrenal transplants which either have or lack gap junctions (Objective 3). The protocols described are expected to increase our knowledge of the role of gap junctions in hormone responses. This information is critical to our understanding not only of hormone response in the adrenal gland but also to a general understanding of organ development, differentiation, and growth.
