Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.6.1.1 (aspartate aminotransferase)
 21,665 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of Centchroman, 3,4-trans-2,2-dimethyl-3-phenyl-4-para-(beta -pyrrolidinoethocy)-phenyl-7-methorychroman, administration was investigated in normospermic and oligospermic subjects. 3 normal volunteers, aged 32-40 years, were treated with increasing doses (30, 60, and 120 mg/day, each dose for 2 weeks). The sperm count was decreased in 1 volunteer but the percentages of nonmotile and abnormal spermatozoa were increased in all 3. There was no change in plasma testosterone and urinary 17-ketosteroid (17-KS) levels but the 17-ketogenic steroids (17-KGSs) were decreased in all of them. 3 out of 5 oligospermic subjects, aged 24-35 years, who received 30 mg/day for 6 weeks revealed increased sperm counts. Plasma testosterone levels were decreased in 4, urinary 17-KGSs were decreased in 2, and 17-KSs were decreased in 1 subject. Acid phosphatase, fructose, sialic acid and glycerylphosphoryl choline levels in semen, and serum glutamate oxaloacetate transaminase, serum glutamate pyruvate transaminase, alkaline phosphatase, and urea in blood were not markedly altered in either group.
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PMID:Effect of Centchroman administration in normospermic & oligospermic individuals. 61 11

The relationship between the antifertility effect of alpha-chlorohydrin and changes in composition of luminal plasma from the cauda epididymidis of rats and rabbits has been investigated. At each dose regimen studied, the fertilizing capacity of rats treated with alpha-chlorohydrin was reduced to zero. The levels of sodium, potassium, glycerylphosphorylcholine (GPC), acid phosphatase and alkaline phosphatase in epididymal plasma were not markedly affected by drug treatment. The most noticeable change was a considerable increase in the concentration of lactic dehydrogenase (LDH) at all dose levels and of glutamic-oxaloacetic transaminase (GOT) after 7 days of treatment with 8 and 16 mg/kg. The effect of cold shock on the composition of epididymal plasma showed that LDH and GOT are, at least in part, derived from spermatozoa. In contrast, alpha-chlorohydrin did not have an antifertility action in the rabbit, and the only notable change in the compositon of epididymal plasma was an increase in the level of GPC. These results provide evidence that, in the rat, alpha-chlorohydrin or a metabolite primarily exerts its antifertility effect by a direct action on the spermatozoa, whilst in the rabbit a barrier may exist to the entrance of the drug into the lumen of the epididymal duct.
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PMID:The effects of alpha-chlorohydrin on the composition of rat and rabbit epididymal plasma: a possible explanation of species difference. 119 43

The possibility of selecting boars for deep freezing of spermatozoa was evaluated by tests of frozen-thawed spermatozoa. 20 of 31 ejaculates were used for artificial insemination of 37 gilts. Boar seminal plasma and OLEP were used as thawing diluents. The thermoresistance test and the extracellular concentration of aspartate aminotransferase (ASAT) were used as indicators of fertility. Spermatozoa from 4 boars were utilized. 1 of the boars appeared to be of superior fertility, while the spermatozoa from another was infertile. The latter animal had been used for fresh artificial insemination trials, and had shown higher pregnancy rates than the average. Samples from this boar exhibited the lowest degree of motility after 3 hours storage at 37 degrees C, the greatest relative decrease of motility during the thermoresistance test, the greatest release of ASAT after thawing by OLEP, and greatest relative release of ASAT. These variations were statistically significant (p less than .05). The results show that there is a possibility of detecting boars with spermatozoa with potential low freezability.
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PMID:Influence of boars on the relationship between fertility and post thawing sperm quality of deep frozen boar spermatozoa. 126 87

1. Gel electrophoresis of aspartate aminotransferase released from boar spermatozoa after cold shock showed one band migrating towards anode. 2. Physico-chemical and kinetic properties of isolated enzyme were similar to cytoplasmic isoenzyme of AAT from somatic tissues.
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PMID:Isolation and characteristics of aspartate aminotransferase from boar spermatozoa. 251 80

Leakage of glutamic-oxaloacetic transaminase (GOT) can be used as an indicator of cryo-damage for mammalian spermatozoa. However, two GOT isozymes exist: mitochondrial (m-GOT) and cytosolic or soluble (s-GOT), with acid and alkaline pH optima, respectively. The levels of these GOT isozymes were determined in samples of cell-free human seminal plasma and sperm extracts over a pH range of 3.8 to 9.6. Optimum GOT activities were found at pH 5.2 using cacodylate-HCl buffer (m-GOT) and pH 8.4 using barbital buffer (s-GOT). Differential inhibition studies with adipate (which inhibits s-GOT) were misleading because of the presence of another NADH-linked enzyme able to use adipate as a substrate. Only relatively low levels of m-GOT could be extracted from human spermatozoa (21.4 +/- 31.5 [SD] mU/10(8) cells vs. 202.3 +/- 49.4 mU/mL seminal plasma; n = 20). Consequently, future studies on GOT leakage should be carried out at the alkaline pH optimum, and will therefore measure s-GOT, making this a marker for plasma membrane integrity rather than a measure of mitochondrial damage.
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PMID:Glutamic-oxaloacetic transaminase isozymes in human seminal plasma and sperm extracts. 290 45

The concentration of testosterone, 17-beta oestradiol and aflatoxin B1 were studied in the semen plasma of 21 boars of four breeds for the period of twelve months. The following spermiological parameters were investigated: semen volume, sperm concentration, percentage of abnormal spermatozoa, and survival of spermatozoa. The fertilizing capacity of ejaculates was evaluated according to the conception rate of sows and gilts after the first insemination, according to the average number of piglets per litter and average number of live-born piglets per litter. The highest aflatoxin B1 residues in sperm were recorded in March to May and were related with aflatoxin concentration in feed ration. The group of boars with fertility disorders had more aflatoxin in their sperm (up to 100 pmol . l-1), lower sperm concentration, lower survival of spermatozoa, and a larger proportion of abnormal spermatozoa. The year season had a significant influence on the concentration of the hormones. The highest average value of testosterone (10.2 +/- 1.28 nmol) was obtained in autumn and lower values were recorded in winter. The changes in 17-beta estradiol concentration were similar to the changes in testosterone content, with the maximum value in November (0.249 nmol X 1(-1]. The boars with reproduction disorders had a significantly lower concentration of 17-beta oestradiol. Significant correlations were found between the concentration of the hormones, semen volume, and sperm concentration. 17-beta oestradiol also had a significant positive correlation to abnormal spermatozoa and to the activity of aspartate aminotransferase.
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PMID:[Fluctuation in the concentration of sex steroids and aflatoxin B1 in the seminal plasma of boars and its relation to sperm production]. 308 6

Polymorphism of non-genetic character was discovered in aspartate aminotransferase (AAT) of bull semen. A relationship was found between the enzyme heterogeneity and susceptibility of plasmatic membranes of spermatozoa to cryogenic damage. The relation changed with the bull's age.
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PMID:Heterogeneity of aspartate aminotransferase (AAT) in bull semen. 356 23

Sperm motility, acrosome morphology, changes determined by the vital-lethal test and aspartate aminotransferase (AST) concentration in semen plasma were evaluated in the semen of four boars; the semen was stored for six years. No statistically significant changes in the percentage of motile spermatozoa were indicated when sperm motility was evaluated after four and six years of semen storage in liquid nitrogen. Neither did the fluctuation of the changes found on the basis of the vital-lethal test go beyond statistically insignificant values. After semen sample thawing in the BTS medium, the motility of spermatozoa was found to be somewhat higher than after thawing in the INRA-ITP medium, but after the termination of the thermoresistance test both media appeared to be equally effective. The AST level of the semen samples stored for four years was just slightly up on the initial values. After thawing in the BTS medium, AST level increased by 0.03 microcatal per litre of semen plasma, and in the INTRA-ITP medium by 0.06 microcatal per litre of semen plasma. The insemination of five sows with the semen stored for six years results in conception of two sows, i. e. 40%, and the average litter size was 7.5 piglets. It can be derived from the results that six years of boar semen storage in liquid nitrogen cause no further substantial changes in the structural and functional characteristics of spermatozoa.
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PMID:[Qualitative changes and the fertilizing capacity of sperm after 6 years of preservation of boar semen]. 392 54

The effect of rapid dilution (1:8 with BTS or 1:6.5 with KRP) and temperature change on sperm morphology and physiology were studied using boar spermatozoa pre-diluted in BF5 diluent. Rapid dilution of cold semen (5 degrees C) with a warm solution (37 degrees C) caused marked acrosomal changes which were most prominent in the anterior region. The acrosomal damage appeared to be caused mainly by rapid warming. In contrast to rapid cooling, rapid warming had little effect upon motility, glutamic-oxaloacetic transaminase release and respiration.
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PMID:Effect of rapid warming of boar semen on sperm morphology and physiology. 403 68

To aid the study of spermatozoa acrosome, ultrastructural changes and midpiece enzyme release were studied in human and rabbit spermatozoa treated with various detergents. Dissolution of the spermatozoa plasma membrane and acrosome was caused by washing with Hyamine 2389 (.15%) and Hyamine 2389 (.075%) with Triton X-100 (.075%). Variable damage to the structures of the tail and midpiece was greater with Hyamine alone than when combined with Triton. Spontaneous midpiece enzyme release and the appearance of aspartate aminotransferase and alanine aminotransferase occurred in the presence of physiological saline. Sonication of the spermatozoa resulted in a greater release of midpiece enzymes than with the detergent treatment. It is concluded that detergent treatment results in more morphologic changes than previously believed, and that although the detergent extracts contain largely acrosomal proteins, ultrastuctural, histochemical and immunohistochemical techniques are necessary for specific localization of a sperm enzyme.
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PMID:Detergent treatment of human and rabbit spermatozoa: ultrastructural changes and release of midpiece enzymes. 446 34


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