Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.1.7 (acetylcholinesterase)
 28,390 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Studied were the indices of cholinesterase activity of semen taken from 23 normal rams and 23 rams infected with Brucella ovis, the latter being positive by the complement-fixation test and showing a varying deterioration of the semen production. The results obtained were processed biometrically. Established were dependable differences. The cholinesterase activity of semen of brucellosis-affected rams proved four times higher than that of normal rams' semen: 39.45 +/- 5.49 microleter TO2 for 1 hour as against 174.15 +/- 9.97 microleter. A reverse correlation was established between the values of the cholinesterase activity, and the pH value and the percent of pathologic forms of spermatozoa.
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PMID:[Cholinesterase activity of sperm from rams infected with Brucella ovis]. 2 57

The effects of physostigmine, a competitive inhibitor of cholinester ases, BW 284C51, a specific and reversible inhibitor of acetylcholinesterase, RO 20683, an inhibitor of nonspecific cholinestera se, acetylcholine and butyrylcholine on the pattern of the flagellar wave and beat frequency, velocity and amplitude of bull and chimpanzee spermatozoa was studied by cinematography. The amplitude of the wave pattern was affected only by BW 284C51. Overall, the variations in frequency and wave pattern were more pronounced than changes in amplitude or velocity. Physotigmine disrupted the coordination of the wave pattern. The results demonstrate the importance of the acetylcholine-acetylcholinesterase system in the regulation of spermatozoan motility.
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PMID:Cholinergic effects on bull and chimpanzee sperm motility. 96 50

We previously reported that intact epididymal spermatozoa from bulls and hamsters oxidize [1-14C]acetyl-L-carnitine to 14CO2 at about the same rate as they oxidize [1-14C]acetate. In addition, we showed that acetylcarnitine is hydrolyzed by a hydrolase present in the plasma membrane and that the carnitine moiety does not enter the cell. Here we report the partial purification of the acetylcarnitine hydrolase from bovine spermatozoa and describe some of its properties. The detergent-extracted enzyme was purified by FPLC using an anion-exchange Mono-Q column. The hydrolase activity eluted from the column with the application of 0.22 to 0.30 M NaCl and was separated from acetylcholinesterase activity, which eluted with 0.35 to 0.40 M NaCl. Specific inhibitors of acetylcholinesterase had little effect on acetylcarnitine hydrolase but p-hydroxymercuriphenylsulfonate was a potent inhibitor of the hydrolase. Kinetic studies of the hydrolase yielded a K'm of 6-10 mM for acetylcarnitine and a V'max of 0.16 nmol min-1 mg protein-1. Similar studies with the acetylcholinesterase yielded a K'm for acetylcholine of about 300 microM and a V'max of 165 nmol min-1 mg protein-1. Acetylcarnitine was a poor substrate for the acetylcholinesterase. Several acyl-L-carnitines were tested as substrates for the hydrolase and the preferred substrate was acetylcarnitine. The role of acetylcarnitine hydrolase in the metabolism of acetylcarnitine by epididymal spermatozoa is discussed.
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PMID:Partial purification and characterization of an acetylcarnitine hydrolase from bovine epididymal spermatozoa. 230 12

Since acetylcarnitine has been identified in the epididymal plasma of many mammalian species, we investigated whether acetylcarnitine could serve as an energy substrate for epididymal bull and hamster spermatozoa. Intact caudal cells from both species oxidized [I-14C]acetyl-l-carnitine to 14CO2, in vitro, and the amount oxidized was dependent on time, substrate concentration, and cell number. Within each species, the rate of oxidation was the same as the rate at which free [1-14C]acetate was oxidized. Spermatozoa incubated with [3H]acetyl-L-carnitine hydrolyzed the compound and [3H]acetate accumulated in the medium. Unlabeled acetate added to the incubation medium competed with cellular uptake of [3H]acetate and resulted in further increase in [3H]acetate accumulation in the medium. Furthermore, the acetyl group of acetylcarnitine was oxidized by spermatozoa without concomitant uptake of the carnitine group. Purified plasma membrane vesicles contained an acetylcarnitine hydrolase activity that was solubilized from whole cells by detergents and that could be distinguished from acetylcholinesterase also present in the cells. The solubilized acetylcarnitine hydrolase activity was inhibited by p-hydroxymercuriphenylsulfonate, but not by the specific acetylcholinesterase inhibitors, eserine or BW63C47. The sulfhydryl blocker also inhibited the production of 14CO2 from [1-14C]acetylcarnitine by intact cells; acetylcholinesterase inhibitors did not. From estimates of sperm energy requirements, our results indicate that extracellular acetylcarnitine serves as a physiologically important energy substrate for maturing sperm cells.
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PMID:The metabolism of acetylcarnitine and acetate by bovine and hamster epididymal spermatozoa. 280 15

The effects of subcutaneous injections of prostaglandins F2a and E1 (100 microgram/day/animal for 30 days) were studied on the histophysiology and contractile pattern of the vas deferens; morphology, density, motility of vasal spermatozoa; and the fertility rate of rats. The results revealed that both the prostaglandins altered the histology, metabolism, and adrenergic response of the vas deferens in comparison to the control. The sperm density and motility were significantly affected and the vas deferens spermatozoa revealed acrosomal, midpiece, and tail damage. Comparison of the effects of the two PGs showed that PGF2a was more effective in altering contractile pattern and cholinesterase activity of the vas deferens; whereas its metabolism, sperm morphology, and density were affected more by PGE1. However, both PGs caused 50% reduction in fertility rate and almost the same level of reduction in sperm motility and protein levels. We suggest that PGF2a and PGE1 have partial antifertility effects as they alter the sperm morphology and antagonize the adrenergic response to the vas deferens by blocking the a-adrenoreceptors.
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PMID:Infertility induced by prostaglandins in albino rats by adrenergic block in the vas deferens. 611 2

The development of motility in porcine spermatozoa as well as the acetylcholinesterase activity of porcine testicular and epididymal spermatozoa in response to chloroquine stimulation were studied. Spermatozoa acquired the capacity for progressive motility as they moved along the epididymis, reaching their peak motility in the caudal portion of the epididymis. Spermatozoal acetylcholinesterase activity declined drastically from the testis to the caput epididymis after which subsequent decline became gradual. Chloroquine stimulation of testicular and epididymal spermatozoa remarkably enhanced sperm motility and the rate of loss of acetylcholinesterase activity only in spermatozoa obtained from the caudal portions of the epididymis. The results indicate that the development of sperm motility during sperm maturation is accompanied by a decline in sperm acetylcholinesterase activity and that the physiological maturity of epididymal sperm could be enhanced by chloroquine stimulation.
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PMID:Effect of chloroquine on the motility and acetylcholinesterase activity of porcine spermatozoa during epididymal maturation. 716 23

Human spermatozoa contain choline acetyltransferase (ChA), acetylcholinesterase and acetylcholine (ACh). There is no storage pool for ACh in spermatozoa. Therefore, ChA inhibitors should exhibit dramatic effects in the alteration of levels and turnover of ACh and sperm motility. The effects of two groups of ChA inhibitors, 2-benzoylethyltrimethylammonium (BETA) and related compounds and halogenoacetylcholines (cholinesters of iodo-, bromo- and chloroacetic acids; XACh, where X = l, Br or Cl), on the motility index of human ejaculated sperm were studied. These investigations gave the following results: 1) BETA was a potent inhibitor of ChA from monkey brain (I50, 4.8 x 10(-6) M), homogenates of rat spermatozoa (I50, 6.5 x 10(-5) M) and homogenates of human spermatozoa (I50, 5.6 x 10(-5) M). It decreased the motility index of human spermatozoa (I50, 8.5 x 10(-8) M) at concentrations higher than 10(-8) M after a contact time of 5 to 60 min. It decreased the motility index of human spermatozoa by about 80% after 5 min and by 95% after 1 hr at a concentration of 10(-6) M. 2) There was a positive relationship between the inhibition of ChA and the depression of the motility index of human spermatozoa among these inhibitors. Both the number of motile cells and the graded motility were decreased. 3) All ChA inhibitors studied are quaternary ammonium compounds that do not significantly cross membrane barriers. 4) Both human sperm cells and human sperm cell homogenates had the same ChA activity. 5) Seventy-five percent of ChA activity could be washed away from human spermatozoa. 6) The same amount of ChA inhibition was observed when BETA was added to the homogenate of sperm cells or whole sperm cells. All of these observations indicate that sperm cell ChA is accessible to BETA and related quaternary ammonium compounds. These studies indicate that ACh is possibly synthesized by the tail and is a local hormone in the coordination of contraction and relaxation cycles of spermatozoan flagella.
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PMID:Inhibition of human sperm motility by inhibitors of choline acetyltransferase. 746 54

The presence of NADPH-diaphorase activity and acetylcholinesterase in the testis, epididymis, vas deferens, seminal vesicle, pelvic plexus, prostate and urethra of man and guinea-pig was investigated with the nitro blue NADPH technique and the thiocholine method, respectively. In human material NADPH-diaphorase activity was found in the Leydig cells, Sertoli cells and the epithelial linings of the rete testis, the excretory ducts, seminal vesicle, prostate and urethra. The guinea-pig material showed staining of the Leydig cells and spermatozoa and similar epithelial staining of the tract as man. Nerves beneath the epithelium and in the muscle layers of cauda epididymis, vas deferens, seminal vesicle, prostate and urethra were also stained. NADPH-diaphorase-positive nerve cells were seen in the pelvic plexus. Some cells also displayed acetylcholinesterase activity but others showed activity for only one of the enzymes or no activity for either enzyme. In the cauda epididymis, vas deferens, seminal vesicle, prostate and urethra acetylcholinesterase-positive nerve fibres formed a plexus beneath the secretory cells. It is concluded that NADPH-diaphorase, generally accepted as a nitric oxide synthase, is present in glandular cells of the male genital tract. The enzyme is also present in nerves, where it is partly co-localized with acetylcholinesterase.
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PMID:NADPH-diaphorase in glandular cells and nerves and its relation to acetylcholinesterase-positive nerves in the male reproductive tract of man and guinea-pig. 969

In this study, the mouse was used to evaluate paternal germline exposure to the organophosphate methamidophos for its potential to produce adverse effects on spermatozoa and in the offspring. There have been reports that organophosphate exposure can increase abnormal sperm morphology in mice. However, effects transmitted to the offspring following paternal exposure have not been reported previously. The maximum tolerated dose (MTD) was 7.5 mg kg(-1) body weight and this dose resulted in no deaths, although blood plasma cholinesterase activity was still decreased. Males were euthanized 4 weeks after an acute intraperitoneal injection of methamidophos (0.5, 3.75, 5.0, and 7.5 mg kg(-1) body wt) and the number of spermatids per gram testes and sperm morphology were analyzed. In this study, abnormal sperm morphology on a per group basis exhibited a dose-response significantly related to increased methamidophos exposure as indicated by regression analysis and a nested ANOVA (p < 0.0001). Preimplantation embryos that were conceived 6 weeks after paternal methamidophos exposure (5 mg kg(-1) body wt) exhibited a significant increase in cleavage arrest. Fertility of males was also affected as shown by a decrease in the number of two- to four-cell embryos per male (postexposure week 6) and an increase in the number of degenerated embryos (postexposure weeks 4-6). We conclude that methamidophos may have the potential to produce transmissible adverse embryonic effects following an acute paternal germline exposure.
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PMID:Paternal effects from methamidophos administration in mice. 1082 10

The reproductive toxicity of the insecticide acephate was studied in male mice. Adult male mice were treated by gavage with acephate at doses of 0, 7, 14, and 28 mg/kg/day for 4 weeks before mating with untreated females. Signs of cholinergic effects were observed in the 28 mg/kg/day group. Brain and skeletal muscle acetylcholinesterase activity was inhibited only in this group. Acephate treatment was associated with a decreased number of implantations and live fetuses, and an increased number of early resorptions at 28 mg/kg/day. The percent morphologically normal spermatozoa was unaffected in all dose groups; however, sperm motility and count were decreased in the 14 and 28 mg/kg/day groups compared to the control. Histologic examination of brain did not reveal any abnormalities. Dose related histologic changes, including degeneration of muscle fibers, were observed in the muscles of male mice treated with any of the doses of acephate. The current study demonstrated adverse effects of male acephate exposure on pregnancy outcome with effects on sperm parameters at 14 and 28 mg/kg/day.
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PMID:Reproductive toxicology of acephate in male mice. 1102 Jun 56


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