Forsbach G

Amenorrhea-galactorrhea associated with Cushing’s disease due to pituitary tumor

Two patients with amenorrhea-galactorrhea and Cushing’s disease due to a pituitary tumor are presented. In both cases, a diagnosis of prolactin-secreting tumor with moderate hyperprolactinemia was established, then Cushing’s disease developed years later. Despite the typical clinical features of Cushing’s disease, a dexamethasone suppression test inhibited both blood ACTH and cortisol concentrations in the 2 patients. Hypophysectomy was performed in 1 case, and the histologic study revealed the presence of a cromophobe adenoma. The other case was treated by external radiation which improved the clinical situation. Clinical and endocrinological studies in these 2 cases were compared with previous reports in the literature in order to discuss the etiology of this unusual association. It is concluded that patients with pituitary tumors presenting moderate hyperprolactinemia may also have excessive secretion of ACTH.

Gestational diabetes mellitus and glucose intolerance in a Mexican population

Objective: To determine the prevalence of gestational diabetes mellitus (GDM), glucose intolerance (GI) and macrosomia in a Latin Mexican population, using the one‐step procedure proposed by the World Health Organization. Method: Consecutive pregnant women (n=667) who attended the antenatal clinic and delivered at the hospital were recruited after 24 weeks of gestation, mean 34.2 weeks, range 24–40 weeks. After a minimum of 3 days with a 150‐g carbohydrate diet, a glucose load of 75 g was administered and 2 h after, a blood sample for glucose was taken, plasma was separated and immediately processed for glucose, using a glucose‐oxidase method. Results: Twenty women were diagnosed with GDM (3%), 87 had GI (13%) and 560 had a normal glucose response (84%). Macrosomia occurred in two (10%) of GDM, in nine (10.3%) of GI, and in 29 (5.4%) gravidas with a normal response, respectively. Only one of the macrosomic infants whose mother had GI, had neonatal hypoglycemia and hyperbilirubinemia. Conclusion: The overall prevalence of glucose abnormalities during pregnancy was 16%. GI in this group was associated to macrosomia at the same rate as GDM.

Pituitary function in human pseudocyesis

Two young women with clinically established pseudocyesis were studied by endometrial biopsy, basal hormonal serum levels and dynamic pituitary testing. Basal serum levels of PRL and TSH were in the normal range; estradiol — 17β, progesterone and FSH were in the follicular phase range, but LH was in the follicular phase range in one patient and in the climateric range in the other one. The histologic assessment of the endometrial biopsies disclosed a proliferative endometrium in both patients. A group of six patients with hypothalamic amenorrhea were subjected to dynamic pituitary testing to compare results with those obtained in the two patients with pseudocyesis. The dynamic pituitary response to GnRH, TRH and metoclopramide was normal in the two patients with pseudocyesis and in the group with hypothalamic amenorrhea; moreover, challenge with estradiol benzoate (EB) in the two patients with pseudocyesis disclosed a normal positive feedback of LH. These observations and the analysis of data already published suggest that the amenorrhea of pseudocyesis is associated neither with a persistent corpus luteum nor chronic hyperprolactinemia. We suggest that an abnormality in neurotransmitter pathways results in alterations of pituitary hormone secretion. However, additional patients must be studied to prove or disprove this hypothesis

The stimulatory effect of estradiol 17-β on prolactin mRNA is inhibited by anti-calmodulin drugs.

The stimulatory action of estrogens on prolactin (PRL) secretion and synthesis is well known; on the other hand, anti-calmodulin drugs have recently been shown to inhibit prolactin in vitro release induced by estrogens. Based on these data, we decided to evaluate the in vivo effect of anti-calmodulin drugs (trifluoperazine and W7) on basal and estradiol-17 beta stimulated levels of PRL mRNA in anterior pituitary lobes obtained from adult male rats. Total RNA was isolated from pooled pituitaries recovered from animals under the same treatment and, from it, hybridizable PRL mRNA was detected. Estradiol-17 beta consistently stimulated PRL mRNA levels by 3-4 fold. The utilization of either trifluoperazine or W7, invariably inhibited estradiol-17 beta stimulated PRL mRNA. Metoclopramide, a drug with antidopaminergic activity, potentiated the stimulatory effect of estradiol-17 beta on PRL mRNA levels. These results suggest that anti-calmodulin drugs have an in vivo antiestrogenic effect on PRL mRNA levels confirming previous in vitro studies. Although, it is difficult to be conclusive about the mechanism through which these drugs act, one possibility is that the calcium-calmodulin system may be involved.