Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Ram "rete testis" fluid (RTF) routinely collected throughout the year has been used as a source of inhibin. The mean flow rate and mean concentration of spermatozoa in the fluid remained constant during the first 12 days of cannulation. More than 50 castrated or cryptorchid rams have been treated with low doses of steroid-free RTF over a 25-h blood sampling period. Human serum albumin was injected as a control. RTF depressed both FSH and LH plasma levels although the pattern was different for each hormone. There was no change in prolactin secretion. LH secretion was affected first while FSH remained unchanged in castrated and in cryptorchid rams. Thereafter, the maximum depression of FSH plasma levels occurred at a time when LH started to return or had returned to preinjection levels in the cryptorchid and castrated animals respectively. In the cryptorchid rams, RTF suppressed pulsatile LH secretion which was present before treatment but in the castrated animals, RTF lowered LH plasma levels which were constant and showed no pulsatile changes before treatment. Both FSH and LH inhibitory activities have been found in all active fractions obtained by purification of RTF. These activities are papain-sensitive and active fractions have a high apparent molecular weight (greater than or equal to 100 000) as shown by gel filtration and ultrafiltration. These and other results in the literature have lead to a re-definition of inhibin as a protein factor of gonadal origin able to depress plasma levels of FSH and LH, even at low doses.
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PMID:Inhibin activity in ram rete testis fluid: depression of plasma FSH and LH in the castrated and cryptorchid ram. 4 91

An overview of immunological contraceptive methods is presented. The most important factors to be considered in developing sperm antigens are specificity in identifying and isolating the antigens and characterizing the resulting immune reactions carefully. Induced autoimmunorchiditis has been tested as a method of contraception with varied results. The resulting destruction of the gonadal tissues occurs without hormonal depression and is reversible. Sperm antibodies have been produced in females by injections of human sperm with varying degrees of effectiveness. Antisperm enzyme isoimmunization in the female inhibits penetration of the sperm or disturbs embryonic development by damaging the sperm. Seminal plasma antigens show less promise for use as contraceptives. Antibodies against spermatozoa may be induced locally with immunoglobulins. Antigens to the zona pellucida are in evidence in every stage of ovulation until the zona is shed. Antibodies to the zona pellucida hinder penetration and implantation of the sperm. The hormones HCS and HCG, which are produced by the placenta, may have contraceptive usefulness. Placental protein antigens must be available in sufficient quantities and must inhibit or interrupt implantation at a very early stage with few side effects. The most common side effect of immunological contraceptive methods is cross-reactive autoimmunity.
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PMID:[Status and developmental trends of immunologic contraceptive technics]. 8 54

The effect of exogenous testosterone on sperm production, seminal quality and libido was studied in 24 stallions. Based on pretreatment data, a stallion was assigned to 1 of 3 groups each containing 8 animals. One member of each group received 0 (Group 1), 50 (Group 2), or 200 micrograms (Group 3) testosterone propionate per kg body weight every 2 days for 88 days. The lower dose of testosterone had no significant effect on most of the parameters studied: the higher dose depressed total scrotal width at Day 90 post-treatment (P less than 0.01), total spermatozoa ejaculated between Days 60 and 90 (P less than 0.01) and 96 progressively motile spermatozoa between Days 60 and 90 (P less than 0.10). One half of the stallions from each treatment were castrated on Day 90. In the operated stallions, the mean number of spermatids per g testicular parenchyma in the controls (Group 1) was significantly (P less than 0.05) higher than that in Group 3 whereas the difference between the number of spermatids/testis in the same stallions of these two groups was significant only at P less than 0.1. Testosterone propionate treatment did not influence time to erection, interval from first mount to ejaculation or number of mounts per ejaculation. The treatment of normal, intact stallions with testosterone propionate did not enhance libido and caused a severe depression of reproductive capacity.
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PMID:Influence of exogenous testosterone on sperm production, seminal quality and libido of stallions. 28 88

Oxidized spermine, an iminoaldehyde (N,N'-bis (3-propionaldehyde) 1,4-diaminobutane), is a non-competitive inhibitor of fructolysis by human spermatozoa. The inhibition constant is about 0.3 mM. In experiments with [U-14C]fructose the iminoaldehyde caused a more pronounced depression of the formation of CO2 than of lactate. The iminoaldehyde was without influence on the conversion of fructose to lactate by cell-free extracts of spermatozoa, but it markedly decreased the uptake of fructose and lactate by spermatozoa. These findings strongly suggest that inhibition of the fructose metabolism of intact spermatozoa was due to interaction of the iminoaldehyde with sperm membranes and not to inhibition of any enzyme of the glycolytic pathway. Several aliphatic and aromatic aldehydes were also tested for their ability to inhibit sugar utilization of human spermatozoa: only n-hexanal exerted an inhibitory effect, the extent of which approached that of oxidized spermine.
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PMID:Mechanism of action of oxidized polyamines on the metabolism of human spermatozoa. 59 91

Male rats were raised from birth in either continuous light (LL) or in 14 h light/10 h dark per day (LD) at 22 +/- 1 degree C. Food and water were administered ad libitum. Groups of rats were killed by decapitation at 14, 20, 25, 35, 41, 45, 51, 55, 58, 63, and 79 days of age. Testicular (TW), ventral prostate (VPW), and seminal vesicle (SVW) weights were measured. Serum concentrations of follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), and androgens were quantified by radioimmunoassay. Results indicate no significant change in TW or spermatogenesis. Spermatozoa were first seen in the lumen of 10% of seminiferous tubules at 35 days of age in both LD and LL rats and by 42 days of age, 80% of tubules from both LD and LL rats contained spermatozoa in the lumen. A highly significant depression in accessory structure development (VPW, SVW) was observed as a result of LL exposure. Serum FSH levels in LL rats were depressed on days 45, 51, 55, and 58 but elevated at 79. Serum PRL concentrations were elevated in LL rats on days 41, 55, 58, 63, and 79, whereas serum androgen levels were depressed on days 58, 63, and 79. Results suggest that exposure to LL results in delayed maturation of the accessory structures in the reproductive system of the male rat possibly as a result of reduced FSH or elevated PRL levels, which in turn may modify the rate and pattern of LH and/or androgen secretion.
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PMID:Sexual maturation of male rats in continuous light. 62 41

1. Excessive amounts of food (two-fold more than the ad libitum intake) introduced into the gastro-intestinal tract of three adult male fowls, for 5 weeks, caused a marked increase in body weight resulting mainly from fat deposition. 2. The induced obesity was accompanied by an increase of the rectal temperature (0-2 to 0-3 degrees C) and a decrease of the skin and comb temperatures, a cessation in the growth of the comb, a reduction in the blood packed cell volume, an eight-fold reduction in the number of spermatozoa in the vasa deferentia and a concomitant depression in their motility. 3. A decrease of the testosterone and an increase of luteinising hormone concentrations in the blood plasma was obtained in two of the three treated birds.
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PMID:Obesity induced by force-feeding and accompanying changes in body temperature and fertility in the male domestic fowl. 115 30

Roosters homozygous for the rose comb allele (R/R) are subfertile. Likewise, roosters bearing the dominant spermatozoal degeneration allele (Sd) are subfertile. The objective of the present research was to see whether these effects were cumulative. Domestic fowl were bred in order to obtain males representing the following genotypes: R/r+ sd+/sd+, R/r+ Sd/sd+, R/R sd+/sd+, and R/R Sd/sd+. Duplicate fertility trials were conducted with Single Comb White Leghorn hens. In each trial, ejaculates were pooled according to genotype. The insemination dose was 1 x 10(8) viable spermatozoa per hen, and eggs were collected over a 21-day interval following a single intravaginal insemination. Fertility over the 21-day period was 53 +/- 2.1 (SEM), 36 +/- 1.6, 21 +/- 2.1, and 11 +/- 1.2%, respectively. Therefore, the effect of homozygosity for the R allele and the presence of the Sd allele were cumulative in the depression of fertility.
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PMID:Analysis of the combined effect of the spermatozoal degeneration allele (Sd) and homozygosity of the rose comb allele (R) on the duration of fertility of roosters (Gallus domesticus). 143 82

EDB significantly depressed GSH in caput and cauda epididymis, but not in testis, 2 hours following injection. This depression was dose-related. EDB enhanced EMS-induced dominant lethal mutations at mating weeks 2 and 3 (of 6). At mating week 2 the fetal death rate was increased two-fold, while at week 3, the fetal death rate had increased to nearly three-fold greater than the EMS-only controls. Enhancement of fetal death rate was confined to postimplantation loss. As with EMS alone, the EDB potentiation of EMS-induced mutations was limited to postmeiotic stages of spermatogenesis. EDB also enhanced alkylation of rat spermatozoa by labeled EMS. Depression of GSH in reproductive tissues is correlated with a potentiation of dominant lethal mutations, as well as an increase in the binding of EMS to sperm heads.
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PMID:Potentiation of ethyl methanesulfonate-induced germ cell mutagenesis and depression of glutathione in male reproductive tissues by 1,2-dibromoethane. 198 7

Norplant capsules and Norplant 2 rods contain levonorgestrel (LNG) that is released slowly for up to 2000 days. After removal the progestogen vanished from the blood stream within 96 hours, and fertility is restored in contrast to the pill contraceptives. Norplant provides a cervix barrier against spermatozoa. About 1/2 of women taking it had anovulation or luteinization of unruptured follicles. In ovulating women the midluteal progesterone values were clearly reduced. There have been some reports concerning the increased aggregation of thrombocytes and the decline of high density lipoprotein (HDL) cholesterol levels in Norplant users. Thrombosis, cerebro- and cardiovascular accidents have not been reported. A longterm prospective study of Norplant 2 users showed an unacceptably high rate of pregnancies after the 4th year, thus the rods have to be replaced after 3 years instead of 5 years. 23% of Norplant 2 and 41% of Norplant users had to resort to removal because of side effects. 54% of Norplant and 48% of Norplant 2 users halted use after 3 years because of menstrual disorders, irregular bleeding, depression, and mood changes. LNG has high affinity to sex hormone binding globulin (SHGB), and it is not active in bound form. The free LNG index was lower in women with unwanted pregnancies than in other women. In 1989 the Population Council reported on 7 phase-3 investigations involving 2470 women. Only 398 completed the 5-year observation period: the cumulative pregnancy rate was 3.5, there were 3 pregnancies among those with body weight of 50-60 kg and 8.6 pregnancies among those weighing 70 kg or more. There were 101 unwanted pregnancies, and 1 child was born with intersexual genitals. Endometrium biopsy or curettage is advised in the event of irregular bleeding especially in women over 40, and about 25% of Norplant users have undergone these procedures.
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PMID:[Norplant]. 210 34

In this study we have shown that IgG class, noncytotoxic, Fc gamma-receptor blocking antilymphocyte antibodies can de detected in a high proportion of patients who have previously been exposed to alloantigens, i.e. multiple transfused uraemic patients, haemophiliacs and male homosexuals. These antilymphocyte antibodies appear to cross-react with human spermatozoa. Monomeric IgG preparations from these patients were also found to significantly impair T-cell responsiveness in vitro. Depression of cell mediated immunity by these antibodies may contribute to prolonged graft survival in uraemic patients but may also predispose to infection.
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PMID:Immunosuppression following alloantigen exposure: a role for lymphocyte Fc gamma-receptor blocking antibodies. 293 21


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