Abstract: 51

IMMUNOLOCALIZATION OF RETINOL BINDING PROTEIN AND CELLULAR RETINOL BINDING PROTEIN IN THE BOVINE OVARY.

J. Alison Brown¹ , Dawn M. Eberhardt¹ , James D. Godkin^{1 *}
Department of Animal Sciences, Univeristy of Tennessee, Knoxville, TN ¹

Retinol and its natural cellular metabolite, retinoic acid, are important signaling molecules in cell differentiation and development. Recent results indicate that retinol may influence follicular and oocyte development. Retinol binding protein (RBP) serves as the systemic and intracellular transport protein for retinol whereas cellular retinol binding protein (CRBP) serves to accumulate retinol and is involved in retinol metabolism. The purpose of this study was to identify the cell specific expression of RBP and CRBP in bovine ovaries. Cattle ovaries were analyzed for the presence of RBP and CRBP using immunohistochemical procedures. Ovaries were fixed in Bouins fixation fluid and embedded in paraffin. Five µm sections were deparaffinized and immunolocalization was performed using antibodies specific for RBP and CRBP. RBP was isolated primarily in the thecal and granulosa cell layers of antral follicles and the granulosa cell layers of some preantral follicles. CRBP exhibited intense immunostaining in granulosa cells of primary, preantral, and early antral follicles. RBP was found within the stroma and blood vessels. CRBP was not found within thecal cell layers of antral follicles, stroma, or blood vessels. RBP, present in healthy, mature follicles, may serve to deliver retinol to the oocyte. CRBP, present in immature, growing follicles, may indicate an important role for retinol in follicular development.

    This abstract is being presented on Sunday, August 1 at 8:00 AM to 10:15 AM at CUB 2nd Floor Ballroom.