Immunocytochemical localization of basic fibroblast growth factor in bovine adrenal gland, ovary, and pituitary

We studied the distribution of basic fibroblast growth factor (bFGF) immunoreactivity in bovine adrenal gland, ovary, and pituitary, using a polyclonal anti-bFGF antibody. In the adrenal gland, the inner layers of the capsule, the zona glomerulosa of the cortex, and the chromaffin cells of the adrenal medulla were intensely stained. In the ovary, follicular epithelial cells of growing follicles and granulosa cells of mature follicles showed strong bFGF-like immunoreactivity. Endocrine cells of the pituitary anterior and intermediate lobes displayed a positive immunoreaction. Blood vessels, including endothelial and smooth muscle cells, as well as stromal cells in all three organs studied, were not stained. This distribution pattern of bFGF immunoreactivity is only partially compatible with the established mitogenic role of this protein, and suggests a wider spectrum of bFGF functions.