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Gonadotropic cells are scattered in the anterior and tuberal lobes and make up 10 to 20% of the anterior pituitary cells. Having a morphofunctional plasticity, they secrete FSH and LH, most often simultaneously. These hormones are stored together in the granulations. In addition, under the action of regulating factors, especially GnRH, the cells can secrete one hormone or the other, or even the alpha subunit. Gonadotropic adenomas range third in frequency among operated pituitary adenomas (12% in our series). The diagnosis is based on the presence of at least 5% of immunoreactive cells with specific antibodies to gonadotropic hormones. These adenomas are distributed into 3 major types: FSH-LH adenoma, the most frequent one, FSH adenoma and alpha-subunit adenoma. The LH adenoma and the beta FSH and beta LH adenomas are very rare. Tumoral gonadotropic cells lose their morphofunctional differentiation. They also lose, to an extent varying according to the cases, their control mechanisms as well as their capacity of synthesis and excretion of both subunits. The alpha subunit, the oldest one in ontogeny, remains the most often and longest-secreted substance. There is a continuum from the gonadotropic adenoma with high plasma gonadotropins levels to the non-functioning adenoma.

In exceptional cases, acromegaly develops as the clinical expression of an ectopic secretion of Growth Hormone (GH) or Growth Hormone-Releasing Factor (GRF), tumorous in origin. In the present report, we describe an instance of acromegaly caused by the secretion of GRF from a voluminous pancreatic tumor. The resection of this tumor resulted in a temporary disappearance of the biological and clinical symptoms of acromegaly, which then reappeared in conjunction with a rise in plasma GRF. From this pancreatic tumor, substances displaying a potent GRF activity were isolated and characterized. Amino acid analyses revealed that they were related to 3 peptides containing respectively 44, 40 and 37 aminoacids. The largest (hp GRF (1-44)-NH2) referred as hp GRF or somatocrinin is considered to be the primary molecule. The pancreatic tumor was multisecreting as proved by high plasma levels of somatostatin, pancreatic polypeptide and glucagon, normalized after the tumor removal, taken together with the immunocytochemical demonstration of the presence of these peptides in the tissue and with the isolation of somatostatin. In contrast hypercalcemia associated with an elevated plasma level of IR-PTH was unmodified by tumor removal. Diagnosis of acromegaly as ectopic endocrine syndrome will probably be facilitated by plasma GRF radioimmunoassay, as a result of production of anti synthetic GRF antibodies.

We studied a 17 year old patient with primary amenorrhea, hirsutixm, clitoral enlargment, poor breast development and 46, XY karyotype. The results shown in table clearly indicate a 17-ketosteroid reductase deficiency. In the view of previously described patients we can conclude that: 1) intensity of virilisation depends on both plasma testosterone and androstenedione levels; 2) importance of gynecomastia depends on plasma E2 but not E1 levels; 3) FSH levels are not correlated with circulating androgens or estrogens but presumably depends on importance of seminiferous tubules' lesions.

Human fetal antehypophysis (16 males, 16 females and 4 unknown sex) were cultivated during several weeks. By immunocytochemistry LH gonadotroph cells were determined with anti-hTSH and anti-pLH serum. The release in vitro of LH and FSH was studied by radioimmunoassay. At the first medium change, the quantity of LH and FSH release was related to the gestational age and sex. A rapid decline of both LH and FSH occured over the 10 first days. There after, a basal release of LH was maintained during several months; the release of FSH was generally maintained at the lower limit of the assay. After 1 month in vitro, the level of LH could not be related to the sex. Release of LH was stimulated by synthetic LRF. A significant increase was observed independently of the sex and age of the fetuses studied.