Effect of various types of intrauterine foreign bodies on the incorporation of 35S into mucoprotein and of thymidine 2-14C into DNA of rat's endometrium

Effect of cupric ions on the initiation protein synthesis rate in the human endometrium

The effect of cupric ions on the initiation protein synthesis rate of the human endometrium was studied. Addition of copper to the complete ribosomal system decreased the binding of [3H]Met-tRNA(i) to the isolated ribosomes with a plateau at about 70% inhibition with concentrations higher than 150 microM. The initiation activity was GTP-dependent with a maximum at 2 mM. This activity was very rapid, requiring 5 min to complete the reaction. Incubation of isolated initiation factors with copper (300 microM) inhibited the formation of the ternary complex. When the complete system was reconstituted with salt-washed ribosomes after ternary complex formation, no significant change on the inhibition pattern was observed. Addition of initiation factors to 5-min preincubated salt-washed ribosomes with 300 microM copper, after the elimination of excess copper, induced only a 12% decrease on Met-tRNA(i) binding. This effect was not modified by the presence of Sparsomycin, an elongation inhibitor. It was concluded that copper interferes with the initiation process, probably at the ternary complex formation level.

The effect of copper on spermatozoal motility and viability evaluated objectively with the aid of the multiple-exposure photography method

The antispermatozoal effect of the copper intrauterine contraceptive device (IUD) was investigated in an attempt to explain one aspect of its contraceptive mechanism. For this purpose, 42 specimens of normal semen were incubated in vitro with the metallic portion of two types of copper IUDs for 24 hours. Periodic determinations of sperm velocity and percentage of motility and viability were performed objectively with the aid of the multiple-exposure photography (MEP) method. No significant effect concerning these parameters was found when specimens were incubated continuously with either type of these IUDs at 23 degrees C. On the contrary, sperm velocity and percentage of motility dropped markedly, and the number of dead spermatozoa increased reciprocally when specimens were incubated with those IUDs at 37 degrees C for 4 hours. However, motility was almost unaffected in specimens that were incubated at 37 degrees C with amounts of copper that exist usually within uterine cavities bearing this sort of IUD. The conclusion was that a copper IUD does not seem to exert its contraceptive effect by inhibiting spermatozoal activity.

Ultrastructural studies on the endometrium of women wearing TCu-200 intrauterine devices by means of transmission and scanning electron microscopy and x-ray dispersive analysis

Endometrial biopsies obtained from 12 young women wearing TCu-200 intrauterine contraceptive devices from six to 12 months were studied by means of transmission and scanning electron microscopes as well as with the use of rubeanic acid stains and x-ray dispersive analysis. Six biopsies were taken at Day 10 and six were taken at Day 20 of the menstrual cycle. The aim was to investigate epithelial and stromal changes possibly related to copper deposition. The main changes were located in the cell organelles at Day 10 of the cycle. The mitochondria disclosed vacuolization of the matrix and myelin figure formation in 70 to 80% of the epithelial cells. There were also increased numbers of lysosomes. There were similar alterations of secretory endometrium in only a few cases. Instead, there was an increased number of mitochondria, and most of them were dividing. Rubeanic acid stains as well as energy-dispersive x-ray analysis failed to reveal significant amounts of copper in the various cell organelles studied. The above observations seem to indicate that there is a definite alteration of the mitochondria of epithelial cells which may result in impairment of respiratory mechanisms and energy production, rendering the endometrial environment inhospitable to the fertilized egg. These changes are thought to be reversible. The absence of copper is explained on the basis of a rapid turnover of the endometrium or to a problem in sampling common to this methodology.

The effect of a copper intrauterine device during the early stages of pregnancy in the rabbit

Copper wire intrauterine devices (CuIUD) were surgically inserted into mature female rabbits 15 days prior to artificial insemination. Gold wire intrauterine devices and sham surgery served as controls. Animals were autopsied 48, 72, 96, 120, 144, and 192 hours after artificial insemination. At autopsies performed 48 to 144 hours after insemination, the reproductive tract was flushed and the embryos were examined. At 192 hours, implantation sites were counted and measured. A significant (P less than 0.05) loss of copper from the devices was observed when the devices were weighed after autopsy. The CuIUD had no effect on ovulation, fertilization, or embryo transport up to 120 hours after artificial insemination. The presence of a CuIUD resulted in a slight, but not statistically significant, increase in embryonic degeneration by 120 hours, almost total absence of blastocysts from the uterus by 144 hours, and complete absence of implantation sites 192 hours after insemination. The antifertility effect of a copper intrauterine device appears to occur in the late preimplantation stage of pregnancy in the rabbit.

Effect of intrauterine copper on the nucleic acids, polysome pattern, and glycoprotein composition of the human endometrium

The modifications induced by the intrauterine release of copper in the macromolecular and glycoprotein composition of the proliferative and secretory human endometrium were studied. In addition, the endometrial changes produced in women users of copper-T intrauterine devices in the polysome pattern and in the content of ribonucleoprotein particles were determined during the secretory phase. A group of ten untreated normal women (control group) and 15 users of 200 mm.-2 copper-T intrauterine device were selected for this study from the outpatient clinic of the Hospital de Ginecologia y Obstetricia No. 2 del Instituto Mexicano del Seguro Social. The main changes observed in the copper-T users were: a significant decrease in the endometrial content of RNA in both phases of the menstrual cycle, a significant decrease in protein in the secretory phase, and drastic changes in the fucose-sialic acid ratios, which decreased during the proliferative and increased during the secretory phases. Normal human secretory endometrium contained 4.89 plus os minus 0.28 (mean plus or minus standard error (S. E.) mg. ribonucleoprotein particle per gram wet weight, while the endometrium of the Cu-T users showed a significant decrease to 2.52 plus or minus 0.17 (mean plus or minus S. E.). In addition, the Cu-T induced a decrease in the heavy components of the polysome pattern with a concomitant increase in the lighter components.