The effect of albumin gradients and human serum on the longevity and fertilizing capacity of human spermatozoa in the hamster ova penetration assay

Luteal phase sera and progesterone enhance sperm penetration in the hamster egg assay

The hormonal factors responsible for variation in sperm penetration rates of zona-free hamster ova caused by the use of human sera were investigated. Sera obtained at different times in the menstrual cycle, 17-beta estradiol (E2), or progesterone (P) was added to Biggers Whitten and Whittingham (BWW) medium used for the sperm penetration assay. Luteal phase sera enhanced egg penetration significantly when compared with either follicular or preovulatory sera (48.8% versus 23% and 25%; P less than 0.01). E2 at concentrations of 2 pg/ml to 2 X 10(6) pg/ml had no effect on sperm motility or egg penetration. Addition of P to control media at final concentrations of 0.5 to 50 ng/ml caused a significant elevation of egg penetration (68% to 91% to 96%; P less than 0.01) without affecting sperm motility. Since P has been shown to have a direct effect on plasma membranes and to bind to spermatozoan plasma membrane, the authors propose that P could have a physiologic role during capacitation or sperm egg interaction in vivo.

Rhesus monkey sperm penetration into zona-free hamster ova: comparison of preparation and culture conditions

A major problem in development of nonhuman primate in vitro fertilization is the selection of donor males and repeated collection of consistent sperm samples. In practice, collection of a viable semen sample is highly dependent on operator technique and the type of animal restraint. We report an updated method for semen collection from the rhesus monkey (Macaca mulatta), use of TES-Tris (TEST) Yolk Buffer (TYB) for prolonged sperm storage and improved results of hamster ovum penetration assay. Semen was obtained from adult males restrained with 2.0 mg/kg IM ketamine hydrochloride prior to direct penile stimulation (Grass SD-9, frequency 150, delay 9, duration 7, volts 12-18, repeat mode, twin pulse). Liquified semen was washed and centrifuged twice at 100 X g for 5 min in BWW, Ham's F-10 and TALP and allowed to swim-up 60 min at 37 degrees in 5% CO2 and air. Alternatively, semen was mixed 1:1 with TYB, refrigerated 20 h at 4 degrees C, centrifuged at 100 X g for 5 min, and the pellet resuspended in 1.0 ml of TALP or BWW prior to use. Hamster ova penetration was achieved with capacitated macaque sperm. Penetration was significantly improved (P less than .001) with preincubation in TYB followed by resuspension in TALP (79%).

Peritoneal fluid in patients with and without endometriosis: prostanoids and macrophages and their effect on the spermatozoa penetration assay

Peritoneal fluid from 35 women with endometriosis and from 34 control women was aspirated at laparoscopy and analyzed. No differences in prostanoid levels were found. The peritoneal fluid volume, macrophage concentration, macrophage content, and content of activated macrophages as measured by acid phosphatase staining were all significantly elevated in the endometriosis patients. The macrophages were incubated and the medium was added to the zona-free hamster egg sperm penetration assay. This medium caused a significant decrease in the percentage of ova penetrated in this assay. It is postulated that one of the mechanisms of infertility in women with endometriosis may involve the increased number of activated macrophages and their ability to interfere with sperm-egg interaction.

The effect of serum on motility of human spermatozoa in culture

The motility of spermatozoa was higher at 6-22 h in Ham's F10 culture medium supplemented with 20-30% human serum than with lower proportions of serum or with 1% human serum albumin. Heat treatment (56 degrees C, 1 h), charcoal extraction and dialysis (18,000 molecular weight cut-off) of the serum did not reduce sperm motility suggesting that high molecular weight components are responsible for maintenance of motility. Renewing the medium (Ham's F10 with 30% serum) at 7 h resulted in better sperm motility and velocity at 22 h. At 22 h the pO2, pCO2, pH and sodium concentrations were not different in replenished and control cultures, but the concentration of glucose was higher and that of potassium lower if the medium was changed. These results suggest that addition of 20-30% human serum and renewal of medium at intervals is beneficial for sperm culture and may be of use in in vitro fertilization.

Semen parameters and capacitation

A relationship exists between several semen parameters and the ability of spermatozoa to capacitate. The increase of oligoteratozoospermia, which could be related to testicular dysfunction, is correlated with the decrease of the percentage of spermatozoa able to "capacitate". The increase of loss of motility with time, which could be related to abnormalities of the seminal fluid, is also correlated with a decreased number of spermatozoa able to "capacitate".

Heavy metal chelators prolong motility and viability of sea urchin sperm by inhibiting spontaneous acrosome reactions

A variety of heavy metal chelating agents is known to prolong the fertilizing capacity and motility of sea urchin sperm. We report here that these agents maintain fertilizing capacity by preventing acrosome reactions which occur spontaneously after dilution of sperm into seawater. These chelating agents also inhibit acrosome reactions induced by high pH or egg jelly. Since induction of the acrosome reaction leads to steps that abolish motility, specifically a massive Ca2+ uptake and concomitant acidification of the cytoplasm, motility is prolonged by these chelators. These observations also suggest that heavy metals play a role in controlling the acrosome reaction in sea urchin sperm.