[Functional morphology of pituitary adenoma in acromegaly].

Twenty-one pituitary adenomas removed from patients with acromegaly were studied electron microscopically. In 9 cases the tumors underwent immunohistochemical analysis by Coons' indirect immunofluorescent technique. Before the operation, all the patients were found by radioimmunoassay to have concentrations of pituitary hormones in the blood serum. A clinico-morphological analysis performed showed that in all cases of acromegaly pituitary adenoma consisted of somatotropocytes differing by the degree of cell granulation. The concentration of the somatotropic hormone (STH) in the blood serum of the patients did not depend on the intensity of the ultrastructural signs of the secretory activity of the cells. In 4 adenomas, a positive immunohistochemical reaction to two hormones, STH and prolactine, was demonstrated.