Abraham Guitelman

Altered pulsatile pattern of luteinizing hormone in men with idiopathic normogonadotropic oligospermia

Gonadotropin serum levels and pulsatile secretion of gonadotropin-releasing hormone (GnRH) and luteinizing hormone (LH) are regulated by sexual steroids and perhaps inhibin, but the relative rates of LH and follicle-stimulating hormone (FSH) secretion are modulated by the frequency of GnRH pulses. This study evaluated LH pulsatility in patients with idiopathic normogonadotropic oligospermia (INO) and normal men before and after clomiphene citrate (CC) administration. INO patients evidenced a lower mean LH levels (P less than 0.001), a higher mean pulse frequency (P less than 0.05) and similar pulse amplitude than normal men. CC induced in normal men a higher LH and testosterone (T) increments and increased pulse amplitude only in normal men. Estradiol (E2) showed no difference in either group. Patients with INO might evidence a hypothalamic disorder that may alter pulsatile GnRH secretion. A different response to CC in patients with INO seems to lend support to a primary hypothalamic lesion. A probable gonadotropin imbalance might alter intratesticular concentrations of T and E2 and be the cause of spermatogenic failure.

Release of Prolactin During Pregnancy: Effect of Sulpiride

The aim of this trial was to study the prolactin-releasing capacity of the pituitary during pregnancy by means of an acute stimulation with sulpiride. Thirty women with normal pregnancies were included in the study (first trimester, nine women; second trimester, eleven women thir trimester, ten women). Each woman received an intramusclar injection of 100 mg of sulpiride sulfate between 8 and 9 A.M. Three similar groups received injections of a saline solution. Blood samples were obtained before and 30 and 60 minutes after the injection. In each sample the prolactin concentration was determined by radioimmunoassay. Basal prolactin levels increased during pregnancy. Significant responses to sulpiride were observed during the three stages of pregnancy, and the levels in the second and third trimesters were higher than those in the firsttrimester. The prolactin-releasing capacity of the pituitary, as judged by the response to sulpiride, seems to be maintained during pregnancy.

Serum Levels of Prolactin in Basal Conditions and after Administration of 2-Bromo-5α-Ergocryptine in Normal and Galactorrheic Subjects

Serum levels of prolactin were measured basally and after the oral administration of 2.5mg of 2-bromo-5α-ergocryptine to healthy male (n=4) and female (n=5) subjects; to women with spontaneous galactorrhea and normal, biphasic cycles (n=3); to galactorrheic women with spontaneous bleeding but no indirect signs of ovulation (n=9); to galactorrheic-amenorrheic women with no evidence of pituitary adenoma (n=19); and to galactorrheic-amenorrheic women with roentgenologic signs of pituitary adenoma (n=4). The drug was given between 8:00 and 9:00 A.M.; blood samples were obtained before and 60, 120, 180, and 240 minutes and 24 hours after the administration of 2-bromo-5α-ergocryptine. Serum levels of prolactin were measured by radioimmunoassay with a double-antibody technique. The mean basal prolactin level in normal men was 12.5±1.0ng/ml; in normal women (7th to 9th days of the cycle) it was 16.2±4.0ng/ml. After drug administration serum levels of prolactin decreased progressively and systematically; minimal values were found at 180 to 240 minutes. The lowest maximal percentage of inhibition in normal subjects was 56%. Basal prolactin levels in galactorrheic women tended to be higher in relation to the severity of the pathophysiologic involvement. The highest levels were found in patients with demonstrable tumors. The drug-induced percentage reduction of these prolactin levels was lower in galactorrheic women than in normal women; paradoxical increases in prolactin levels occurred in some cases. The wide variability of the results obtained in the galactorrheic groups would restrict the practical application of this testing procedure.