Ovarian superstimulatory response and embryo production in mares treated with equine pituitary extract twice daily.

Equine pituitary extract (EPE), has been reported to induce multiple ovulation in mares, however ovulation rates are poor in comparison to those obtained in other species. Attempts to improve the effectiveness of EPE for induction of superovulation in cyclic mares has focused on daily frequency of EPE treatment. Two experiments were performed to compare the ovarian response of cyclic mares given EPE once or twice-daily. Mares were assigned to one of two treatment groups 6 to 8 days after ovulation: prostaglandin was given once and EPE (25 mg) was given once daily (Group 1) or twice daily (Group 2). In Experiment 1, more (P < 0.05) follicles > or = 35 mm were detected in mares treated with EPE twice daily (6.1 +/- 3.1) than in mares treated once a daily (2.0 +/- 0.6). In a second experiment, the embryo recovery rates of mares given the two EPE protocols used in Experiment 1 were compared. The number of ovulations per mare was higher (P < 0.05) for mares treated twice-daily (7.1 +/- 5.1, range 3 to 18) than for mares treated once daily (2.4 +/- 1.8, range 1 to 6). The number of embryos produced per mare was higher (P < 0.05) in mares in Group 2 (3.5) than in Group 1 (1.6). Although it is not clear whether the increased ovulation rate is due specifically to dose or frequency, twice-daily administration of a high dose of EPE significantly improved follicular development, ovulation and embryo recovery over the standard treatment of once-daily injection.

Laparoscopic interstitial contact laser ablation of renal lesions: an experimental model.

Tissue ablation with the interstitial Nd:YAG contact laser is a rapidly evolving technique. The urologic applications of interstitial lasers have not been fully investigated. We developed a model to test the feasibility of using interstitial laser energy, administered under laparoscopic guidance, to ablate porcine renal tissue. Utilizing a synthetic sapphire interstitial Nd:YAG contact probe, minimal tissue effects were observed using total energies between 120 and 240 J. At energies of 480 J (8 W/60 seconds), there was predominantly coagulation necrosis of the renal parenchyma. At 720 J (12 W/60 seconds), there was pronounced tissue vaporization surrounded by a zone of coagulation necrosis approximately 1.5 cm across. This preliminary investigation demonstrates that the interstitial Nd:YAG contact laser probe can be used for both controlled coagulation necrosis and vaporization of renal parenchymal tissue. This approach may be applicable to the laparoscopic ablation of small renal lesions in selected patients.

Objective assessment of spermatogenesis in men with functional and anatomic obstruction of the genital tract.

Experimental rodent models simulating the condition of neurogenic infertility have drawn attention to the role of potential epididymal dysfunction as an underlying cause. This functional obstruction of the genital tract is comparable to the outcome of genital tract obstruction after vasectomy, and may explain the common finding of asthenospermia in both groups following either stimulated semen recovery or vasovasostomy, respectively. Since spermatogenic dysfunction has been reported in spinal cord injury, the relative roles of defective sperm production and sperm transport remain to be determined in men with neurogenic infertility. The objective of this study was to compare the levels of spermatogenesis in groups of vasectomized men and those with spinal cord injury, using objective measurement criteria for spermatogenesis. Groups of 10 spinal cord-injured and six vasectomized men matched for age and duration of disease, underwent incisional testicular biopsy. The specimens were divided equally for parallel quantitation of spermatogenesis by both quantitative cytometry and DNA flow cytometric analysis. Quantitative parameters showed similar values for both groups with reference to mean tubular wall thickness, mean tubular concentration of spermatids and Sertoli cells, as well as the mean spermatid: Sertoli cell ratio per tubule. Additionally, similar percentages of 1N, 2N and 4N cells, were found in both groups. Based on these preliminary findings this study provides a clinical correlation supporting the experimental observation that both anatomical and functional obstruction of the male genital tract exert a similar although minor spermatogenic insult, and that in both the putative cause for neurogenic infertility is more likely to be at the post-testicular level.