[Kinetic study of pulsatility of gonadotropin and testosterone secretion in normospermic fertile and infertile men with idiopathic oligo-asthenozoospermia].

Idiopathic oligo-asthenozoospermia is among the most frequent causes of male infertility and has a not very well understood etiopathogenesis. To obtain valuable information about the role of some endocrine factors in the etiology of this kind of infertility, information that is not easy obtain by the traditional analytical methods, we applied some recently proposed mathematical algorithms to analyze with more exactitude the importance of the secretory pulses of three hormones, luteinizing hormone (LH), follicle stimulating hormone (FSH) and testosterone (T). Serum samples were obtained every 10 min for 12 h, from 15 fertile normospermic men and 14 infertile patients with idiopathic oligo-asthenozoospermia; the concentration profiles of FSH and T were analyzed by IRMA and RIA, and the immuno-and bioactive LH concentrations were quantified by IRMA and bioassay (JCEM 42:958, 1976). To assess the pituitary stores of LH and FSH, after 8 h of spontaneous secretion we administered (2 h apart) 2 intravenous pulses containing 10 micrograms of a GnRH analog, and the sampling continued as described. Hormonal pulsatility was assessed by a computerized cluster analysis method (Am J Phys 250:E486, 1986) an by the multiple parameters deconvolution method (JCEM 66: 1291, 1988). In the infertile patients we found a significant diminution in the length and frequency of LH pulses, compared with the normospermic men. However, LH half life, the interpulse interval, the amplitude and the mass secreted per pulse rose in the infertile males compared with the controls. The increase in the LH half life suggests the secretion of a more acidic isoform of this hormone in the infertile group. After the GnRH injection the LH secreted mass and mean concentration rose significantly in both groups; this effect was higher in the infertile oligo-asthenozoospermic men. In this group we also found a decrease in the bioactive LH interpulse interval and therefore more pulses during the sampling interval, that produced a higher concentration of this kind of hormone in these patients. Oligo-asthenozoospermic men secreted approximately 70% more bioactive LH as a response to the first GnRH injection than the normal controls. The desensitization observed with immunoactive LH (diminution in the mass secreted after the second GnRH bolus compared with the first one) was also observed with bioactive LH. In the infertile men group we found a significant reduction in the FSH half life compared with the normospermic controls; this fact suggests that, contrarily to the results observed with LH, a more basic isoform is secreted in these patients.(ABSTRACT TRUNCATED AT 400 WORDS)