Ewes heterozygous (I+) for the Inverdale prolificacy gene (FecXI) located on the X chromosome have ovulation rates about 1.0 units higher than noncarriers. The purpose of this study was to examine the reproductive performance of ewes that were either heterozygous or homozygous (II) carriers of the Inverdale gene. Carrier rams (I) were mated with heterozygous ewes (I+) to produce females, half of which were expected to be I+ and half II. The 59 female progeny were examined by laparoscopy at 8 mo or 1.5 yr of age; 48% were found to have nonfunctional "streak" ovaries, which were about one eighth the volume of normal ovaries and showed no sign of follicular activity. There were four examples of full sib pairs where within each pair one had normal ovaries and the other had streak ovaries. Since these streak ovaries have not been observed in ewes known to be I+ or noncarriers (++), it is concluded that this condition is associated with animals homozygous for the Inverdale gene.
The present study investigated whether high oestradiol concentrations after ovarian stimulation in infertile women affect endometrial development around the time of implantation. The glandular and stromal components of the endometrium were assessed by morphometric criteria. Endometrial biopsies were taken on day 7 (+/-1) after the ovulating dose of human chorionic gonadotrophin in stimulation cycles and on day 7 after the LH surge in natural cycles. Women (n = 38) undergoing assisted reproduction treatment were evaluated: 12 women in natural cycles, 11 women in stimulation cycles with oestradiol <20,000 pmol/l and failed fertilization after oocyte collection (moderate responders) and 15 women with an oestradiol concentration of > or =20,000 pmol/l in stimulation cycles (high responders). High responders showed delayed glandular maturation and advanced stromal morphology, whereas moderate responders demonstrated synchronous development of glandular and stromal features. In natural cycles, the glands were in phase. The effect of excessively high oestradiol concentrations could be explained by quantitative evaluation of the endometrial biopsies as gland--stromal dyssynchrony, which indicates a deficient secretory transformation of the endometrium that represents a suboptimal endometrial environment for implantation. This substantiates our previous clinical observation of significantly lower pregnancy rates in IVF cycles of women with high oestradiol concentrations (> or =20,000 pmol/l).
Recently, we reported that male accessory sex gland (ASG) secretions protect sperm genomic integrity by demonstrating that DNA damage was more extensive in sperm not exposed to the secretions. The present study was conducted to find out if ASGs secrete the main antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidase (GPx or GSH-Px), and catalase (CAT) and if the most abundant one, SOD, can protect those sperm that were not exposed to ASG secretions against NADPH-induced oxidative stress. Four experimental groups of male golden hamsters were used: intact animals with proven fertility, animals with all major ASGs removed (TX), animals that were bilaterally vasectomized, and sham-operated controls. SOD, CAT, and GPx activities were measured in secretions from all 5 ASGs and sperm-free uterine flushing from virgin females and those mated with the experimental males. The alkaline comet assay was used to analyze DNA integrity of the TX group sperm after incubation in a medium containing 50 U/mL of SOD along with 0 to 20 mmol/L NADPH. The main antioxidant enzyme in ASGs was SOD from coagulating glands (P <.05) and GPx together with CAT from ampullary glands (P <.05). Uterine flushing of ejaculates that contained ASG secretions had more SOD and CAT activities than those with epididymal secretions alone (P <.05 and P <.001, respectively), whereas activity of GPx was the same (P >.05). Addition of SOD in vitro dose dependently decreased the incidence of single-strand DNA damage in sperm not exposed to ASG secretions incubated in the presence of 0 to 20 mmol/L NADPH (P <.001). These results indicated that, in terms of abundance, SOD was the main antioxidant enzyme secreted by male ASGs, whereas CAT was the second one. The GPx activity came from both epididymis and ASGs. We conclude that ASG secretions play a significant role in protecting sperm against oxidative stress.
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