PubMed HealthSearch

SEARCH · PubMed Health

Results for “Fertility Agents”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

Mode of action of alpha-chlorohydrin as a male anti-fertility agent. Inhibition of the metabolism of ram spermatozoa by alpha-chlorohydrin and location of block in glycolysis.

1. The effect of alpha-chlorohydrin on the metabolism of glycolytic and tricarboxylate-cycle substrates by ram spermatozoa was investigated. The utilization and oxidation of fructose and triose phosphate were much more sensitive to inhibition by alpha-chlorohydrin (0.1-1.0mm) than lactate or pyruvate. Inhibition of glycolysis by alpha-chlorohydrin is concluded to be between triose phosphate and pyruvate formation. Oxidation of glycerol was not as severely inhibited as that of the triose phosphate. This unexpected finding can be explained in terms of competition between glycerol and alpha-chlorohydrin. A second, much less sensitive site, of alpha-chlorohydrin inhibition appears to be associated with production of acetyl-CoA from exogenous and endogenous fatty acids. 2. Measurement of the glycolytic intermediates after incubation of spermatozoal suspensions with 15mm-fructose in the presence of 3mm-alpha-chlorohydrin showed a ;block' in the conversion of glyceraldehyde 3-phosphate into 3-phosphoglycerate. alpha-Chlorohydrin also caused conversion of most of the ATP in spermatozoa into AMP. After incubation with 3mm-alpha-chlorohydrin, glyceraldehyde 3-phosphate dehydrogenase and triose phosphate isomerase activities were decreased by approx. 90% and 80% respectively, and in some experiments aldolase was also inhibited. Other glycolytic enzymes were not affected by a low concentration (0.3mm) of alpha-chlorohydrin. Loss of motility of spermatozoa paralleled the decrease in glyceraldehyde 3-phosphate dehydrogenase activity. alpha-Chlorohydrin, however, did not inhibit glyceraldehyde 3-phosphate dehydrogenase or triose phosphate isomerase in sonicated enzyme preparations when added to the assay cuvette. 3. Measurement of intermediates and glycolytic enzymes in ejaculated spermatozoa before, during and after injection of rams with alpha-chlorohydrin (25mg/kg body wt.) confirmed a severe block in glycolysis in vivo at the site of triose phosphate conversion into 3-phosphoglycerate within 24h of the first injection. Glyceraldehyde 3-phosphate dehydrogenase activity was no longer detectable and both aldolase and triose phosphate isomerase were severely inhibited. Spermatozoal ATP decreased by 92% at this time, being quantitatively converted into AMP. At 1 month after injection of alpha-chlorohydrin glycolytic intermediate concentrations returned to normal in the spermatozoa but ATP was still only 38% of the pre-injection concentration. Motility of spermatozoa was, however, as good as during the pre-injection period. The activity of the inhibited enzymes also returned to normal during the recovery period and 26 days after injection were close to pre-injection values. 4. An unknown metabolic product of alpha-chlorohydrin is suggested to inhibit glyceraldehyde 3-phosphate dehydrogenase and triose phosphate isomerase of spermatozoa. This results in a lower ATP content, motility and fertility of the spermatozoa. Glycidol was shown not to be an active intermediate of alpha-chlorohydrin in vitro.

Animals

Effect of fertility regulating agents on motility and zona-free hamster egg penetration by spermatozoa of bonnet monkey.

Administration of STS-557 (17 alpha-cyanomethyl-17 beta-hydroxyestra 4,9(10)-dien-3-one; 12 mg/monkey daily) for 4 weeks either alone or in combination with 20 Aet-1 (testosterone-trans-4-n-butyl cyclohexyl carboxylate; code CDB 1781; 40 mg/monkey single administration) had no significant effect on motility and zona free hamster egg penetration by spermatozoa of bonnet monkey, but continuation of the treatment for 12 weeks reduced (in one monkey treated with STS-557) or abolished (one treated with STS-557 and two with STS-557 + 20 Aet-1) the motility as well as zona-free hamster egg penetration (by spermatozoa of all treated monkeys). Motility and the ability to penetrate zona-free hamster egg returned to normalcy after 10 weeks of withdrawal of treatments. Active immunization of monkeys with ovine FSH (4 weeks after booster) had no adverse effect on motility of spermatozoa but none of the zona-free hamster eggs was fertilized. The correlation between motility and the capacity to penetrate the zona-free hamster eggs by monkey spermatozoa varies with the treatment. Such correlation was apparent in monkeys treated with STS-557 but not in monkeys immunized with ovine FSH.

Animals

Post-coital contraceptive effects of an agonistic analogue of luteinizing hormone releasing hormone.

An analogue of synthetic hypothalamic LRH, D-[ALA]6-DES-[GLY]10-PRO9-ethylamide-LRH (Wy-18,481) was evaluated for agonistic (in vivo LH-releasing and ovulation-inducing), post-coital contraceptive and reproductive target organ effects. Both LRH and the analogue terminated pregnancy; there appeared to be a direct relationship between agonistic and post-coital contraceptive potency and activity. The analogue proved to be a potent agonist and both a pre-and post-implantational post-coital anti-fertility agent. In contrast to LRH, the congener did not produce a uterotrophic effect in the hypophysectomized rat. The data suggest that agonist analogue(s) of LRH can terminate pregnancy via hyperstimulation of the pituitary-ovarian-reproductive complex and the use of members of this neurohormonal class as potential clinical pro-fertility agents should be weighted with caution.

Animals

[Two hundred and sixty eigth medicinal plants used to fertility control in some countries of South America (author's transl)].

A review is made of the various anthropological, botanical and empirical medical papers from a number of the countries of the South-American continent, whose populations use medical plants for fertility control. Also included is a field research conducted among indigenous and rural populations of Paraguay. The scientific name, family and common name 268 plants are described. With each plant, the country and type of population (indigenous or rural) using same is stated, as well as their empiric properties attributed to same and the name of the author. Comments are made upon the background related to the use of said plants at the level of the American indigenous, world folkloric and Paraguayan indigenous & folkloric medicine. Emphasis is given to the significance of these data on contraceptives, abortives, sterilization and fertilization agents of vegetal origin, due to their value for future research in the physiology and clinic of reproduction.

Abortifacient Agents

Reversible anti-fertility effect by non-occluding oviductal copper coils in the rabbit.

Placement of two 1 cm copper (Cu) coils around the mid-region of each oviduct in a group of five female rabbits with proven fertility, 34 days before mating, virtually prevented fetal implantation in these animals. The oviducts remained patent during a 47 day implantation period and following removal of the Cu coils, does that were remated became pregnant. In two of these does an implantation rate (living fetuses/corpora lutea) of 33% (7/21) was observed and one post-Cu implanted doe had a litter of two. Among four does bearing a single Cu coil on their left oviduct for 28 days prior to mating there was 19% (4/21) implantation of the left side and 56.3% (9/16) on the untreated right side, suggesting a local action by the metal. The results indicate that Cu is an effective anti-fertility agent when implanted around the oviducts and, as a corollary, it is apparent that the metal is not restricted to placement in the uterus in order to prevent pregnancy in rabbits. Non-occluding Cu containing devices may offer a new approach to reversible fertility control in the female that merits further investigation.

Animals

Effect of gossypol on the ultrastructure of rat spermatozoa.

Gossypol was found to induce sterility in male rats when administered orally. A reduction in the number of spermatozoa in the epididymis from the gossypol-treated rats was observed when compared to the control animals. An examination of the spermatozoa from the treated rats showed the following ultrastructural modifications: disorganization of the mitochondiral sheath and missing cell membrane from the middle piece, broken cell membrane and missing members of both outer fibers and inner microtubules of the principal piece, and broken cell membrane of the sperm head. Serial mating experiments proved that gossypol-treated males were indeed sterile. The results suggest that gossypol at low concentrations is able to affect the motility of spermatozoa, thus contributing to its contraceptive action.

Animals

Steroids and related products. XLI. (1) the synthesis of 11-oxa steroids. III. (2) 17-acetoxy-11-oxaprogesterone (3).

The synthesis of 17-acetoxy-11-oxaprogesterone, the 11-oxa analogue of the orally active progestational and anti-fertility agent 17-acetoxyprogesterone, is described. An intermediate in the synthesis of 11-oxaprogesterone, 11-oxa-5alpha-pregnane-3,20-dione, available from hecogenin, was used as starting material and the 17-hydroxy function was introduced by a modified Barton oxidation. The new hormone analogue shows only extremely weak progestational activity in the oral Clauberg assay.

Contraceptives, Oral

Measurement of the cell migration index with a HeNe laser.

Human diploid fibroblasts (WI38) were inoculated into Rose multipurpose culture chambers, using a high population density to develop confluency. After 24 hours, cells from a 1 mm swath were scraped from the center of the chamber. This cleared path was positioned to permit an unobstructed transmission of a 0.9 X 20 mm beam of light from a 1 mW HeNe laser. As cells migrated, at 37 degrees C, into the path of the laser beam the light scatter was recorded, using a photomultiplier tube. Because the amount of light scatter was proportional to the number of cells migrating into the beam, the system measured the migration index of the cells. Slight variations in the design of this device could facilitate data collection during surveys of toxic agents, fertility tests, and delayed hypersensitivity.

Cell Movement