IMMUNOCYTOCHEMICAL INVESTIGATIONS ON THE VASCULARIZATION OF PITUITARY-ADENOMAS

Blood vessels within pituitary adenomas were visualized using the immu nocytochemical reaction for Factor VIII (von Willebrand Factor), a spe cific marker of the vascular endothelium. The number of immunopositive vascular profiles were counted and expressed as a mean number per one microscopic field. The results were related to the type of adenoma, e stablished on the basis of immunocytochemical investigation using the antibodies against pituitary hormones or alpha-subunit (alpha-SU). It was found that the richest vascularization occurred in adenomas expres sing follicle-stimulating hormone (FSH). The possible role of FSH in p ituitary angiogenesis is discussed.