Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.6.1.3 (ATPase)
 65,361 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Human seminal plasma contains organelles (granules and vesicles) of prostatic origin. A Mg2+- and Ca2+-dependent ATPase activity, associated with the membranes of the organelles, was determined and related to the contents of calcium, magnesium and zinc in the granules. The samples were obtained from total ejaculates of 42 men. Fourteen had normal spermiograms. Sperm-free, post-vasectomy ejaculates were obtained in 12 cases. In 16 other men, 9 had sperm concentrations less than 40 X 10(6)/ml and 7 had asthenospermia and/or teratazoospermia. No statistically significant intergroup differences were found when the organelle contents of the metals were determined with flameless atomic absorption spectroscopy. In fractionated ejaculate specimens, the distribution of the metals was correlated to the organelles rather than to the amorphous substance also present in ejaculate. In comparison with the surrounding seminal plasma, an unambiguous enrichment of metals was obtained in the organelles. It is suggested that the organelles exert a regulatory function on spermatozoa by modulating in their microenvironment the concentration of divalent cations necessary for the spermatozoan motility.
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PMID:Calcium, magnesium, and zinc contents in organelles of prostatic origin in human seminal plasma. 621 56

During attempts to isolate bovine sperm actin, persistent low molecular weight proteinaceous (LMWP) contaminants were found. A LMWP fraction was prepared by gel filtration chromatography on Sephadex G150. The LMWP was found in extracts of washed bovine ejaculated spermatozoa and in clarified bovine seminal plasma. It was substantially reduced in amount in bovine epididymal spermatozoa, indicating that it originated from secondary sex gland secretions. The LMWP inhibited rabbit muscle actin-stimulated myosin adenosine triphosphatase (actin-myosin ATPase) activity. The LMWP:actin ratio for 50% inhibition of actin-myosin ATPase was 2.6 +/- 0.12 mg LMWP per mg actin. The LMWP interfered with actin inhibition of deoxyribonuclease, indicating that LMWP interacted with actin. The LMWP from seminal plasma had an estimated molecular weight of 8300 and consisted of several acidic components. It had negligible protease activity and its inhibition of actin-myosin ATPase was independent of divalent cations. The LMWP appears to readily aggregate with itself and other proteins, which may be related to its physiological role in semen.
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PMID:A bovine seminal plasma inhibitor of actin-stimulated myosin adenosine triphosphatase. 622 26

Male patients displaying an immotile or almost immotile sperm population are the object of an interdisciplinary study concerning a ciliary mutant that induces the "Immotile-Cilia Syndrome". Development and function of both sperm flagella and cilia are normally affected because of disturbances of the 9 + 2-arrangement. During this program, clinical, physiological, genetical and ultrastructural investigations were done. The ultrastructure of immotile spermatozoa of an infertile man did not reveal inner and outer dynein arms. Lack of the ATPase dynein which is essential for movement of the 9 + 2-axoneme, is typical for the above syndrome. In addition, symmetry of the fibrous sheath of the spermatozoa was very abnormal. The pneumologist examined normal lung function, where the ultrastructure of the cilia of the nasal mucosa displayed the dynein arms. Analysis of family tree and chromosomes by the geneticist also gave a normal result. As revealed by this infertile patient it seems likely that expression of dynein must not be identical in both germ cells and somatic cells. Such variations are therefore regarded as additional forms of the "Immotile-Cilia syndrome". Asymmetric fibrous sheaths are thought to be a result of immotile spermatid flagella, leading to an abnormal arrangement of the accessory axonemal structures. Normal early spermatid flagella of man and rat show specific movements.
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PMID:Mosaicism of dynein in spermatozoa and cilia and fibrous sheath aberrations in an infertile man. 622 63

Damage to the plasma membrane of rabbit epididymal spermatozoa during spontaneous lipid peroxidation was examined by means of trypan blue uptake and expression of activity of the intracellular enzymes, lactate dehydrogenase and pyruvate kinase. Both the dye uptake and the expression of enzyme activity probe cell damage from lipid peroxidation as loss of integrity of the plasma membrane. A linear correlation was obtained between trypan blue staining of the cells and malondialdehyde production, a quantifiable measure of the extent of lipid peroxidation. At the point of trypan blue staining of all cells, 0.5 nmol malondialdehyde/10(8) cells was produced. This is the same amount produced at the point of complete loss of motility and superoxide dismutase activity. We have defined this as the "lipoperoxidative lethal end point." Expression of lactate dehydrogenase and pyruvate kinase activities increased with time of aerobic incubation. In the high Na+ medium, NTP, in which lipid peroxidation is slow, there is a linear correlation between increase in expressed enzyme activities and malondialdehyde production. But in the high K+ medium, KTP, in which lipid peroxidation is rapid, there is an initial rapid rise in expressed enzyme activity over 3 h, followed by a slower increase. Activities of rabbit sperm lactate dehydrogenase, pyruvate kinase, and flagellar ATPase were unaffected by aerobic incubations for up to 48 h, double the incubation period used for the assay of enzymatic activities for the first two. The activity of glyceraldehyde-3-phosphate dehydrogenase decreased during aerobic incubation, the time course matching the loss of motility. The subcellular distribution of lactate dehydrogenase in rabbit spermatozoa was determined: 4% in the mitochondrial matrix, 10% in the plasma membrane and 85% in the cytosolic compartment.
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PMID:Assessment of cell damage caused by spontaneous lipid peroxidation in rabbit spermatozoa. 623 Oct 58

The present paper deals with the correlative histochemical and biochemical studies of the epididymis following the treatments of alpha-chlorohydrin. This drug was administered in chronic low dose (15 mg/kg body weight/day) for 20 and 30 days and a single high dose (90 mg/kg body weight). Histochemical alterations of ATPase, SDH and AChE were studied in various components of epididymal epithelium and the total enzyme content was measured by biochemical parameters. The study shows progressive decrease of the enzymes in the interstitium and the epithelium of both the caput and cauda epididymes with increasing dose and duration, except for the high dose effect of alpha-chlorohydrin on AChE. Since alpha-chlorohydrin decreases the androgen dependent enzymes (ATPase, SDH, AChE), there is a possibility that the drug may be antiandrogenic in nature. In such case the action of these drugs may not be directly on the spermatozoa, as proposed by earlier workers, but is mediated by changing the physiology of the epididymis, affecting the milieu in which the spermatozoa mature.
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PMID:Correlative histochemical and biochemical studies on the adenosine triphosphatase, succinic dehydrogenase and acetylcholinesterase in the epididymis of mice after alpha-chlorohydrin treatment. 623 98

The cardiac glycoside, ouabain, exerts its influence on spermatozoa by binding to and inhibiting Mg2+-activated Na+, K+-dependent ATPase that is located in the midpiece-tail membranes. Ouabain decreased intracellular potassium, increased intracellular sodium, and produced a biphasic and time-dependent effect on motility--stimulation at low concentrations and inhibition at high concentrations. The motility depression consisted of decreases in numbers of motile cells, percent progressive motility, beat frequency, and amplitude. Species differences and maturational age of the sperm cells were reflected in the degree of the ouabain effect and also the distribution of the ouabain-sensitive enzyme. The presence of this enzyme in spermatozoan membranes contributes significantly to regulation of sperm cell function through modulation of cationic fluxes which in "conventional" cell types influence their excitability.
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PMID:Effects of ouabain on spermatozoan function: a review. 626 5

Plasma membrane vesicles, isolated from ejaculated ram sperm, were found to contain Ca2+-activated Mg2+-ATPase and Ca2+ transport activities. Membrane vesicles that were exposed to oxalate as a Ca2+-trapping agent accumulated Ca2+ in the presence of Mg2+ and ATP. The Vmax for Ca2+ uptake was 33 nmol/mg protein per h, and the Km values for Ca2+ and ATP were 2.5 microM and 45 microM, respectively. 1 microM of the Ca2+ ionophore A23187, added initially, completely inhibited net Ca2+ uptake and, if added later, caused the release of Ca2+ previously accumulated. A Ca2+-activated ATPase was present in the same membrane vesicles which had a Vmax of 1.5 mumol/mg protein per h at free Ca2+ concentration of 10 microM. This Ca2+-ATPase had Km values of 4.5 microM and 110 microM for Ca2+ and ATP, respectively. This kinetic parameter was similar to that observed for uptake of Ca2+ by the vesicles. The Ca2+-ATPase activity was insensitive to ouabain. Both Ca2+ transport and Ca2+-ATPase activity were inhibited by the flavonoid quercetin. Thus, ram spermatozoa plasma membranes have both a Ca2+ transport activity and a Ca2+-stimulated ATPase activity with similar substrate affinities and specificities and similar sensitivity to quercetin.
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PMID:Calcium transport and Ca2+-ATPase activity in ram spermatozoa plasma membrane vesicles. 629 78

Effects of the addition of 100 micrograms each of prostaglandins E1, E2, F1a and F2a were seen on the motility, fructose utilization and total ATPase activity of human spermatozoa. PGE2 enhanced sperm motility and fructose utilization and decreased the whole sperm ATPase activity. While PGE1 had no effect on any of the parameters studied, PGF1a and PGF2a decreased sperm motility to some extent. Fructose utilization was reduced after PGF1a addition only. No change in the activity of ATPase was observed after treatment with F series of prostaglandins.
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PMID:Effects of prostaglandins E-1, E-2, F-1a and F-2a on human sperm motility. 644 48

The three main segments of the elephant epididymis were examined for the occurrence, in the spermatozoa and lining epithelium, of carbohydrates, neutral lipids and phospholipids, ATPase, alkaline phosphatase, succinic dehydrogenase, glucose-6-phosphate dehydrogenase, diaphorases, hydroxysteroid dehydrogenases, acid phosphatase and non-specific esterase. The most distinct feature of the carbohydrate content of the epididymis was a layer of acidic, alcian blue-positive glycoprotein over the luminal surface of the epithelium, particularly in the terminal segment. PAS-positive, diastase-resistant inclusions were also found throughout the epdidymis. Neutral lipid occurred as droplets above and below the nucleus in the epithelium of the middle segment, and as supranuclear accumulations in the terminal segment. All the enzymes except the steroid dehydrogenases were detected in the epididymal epithelium, and all except the steroid dehydrogenases and acid phosphatase were detected in the spermatozoa. There was considerable variation in the intensity of the cytochemical reactions in the epithelium, but not in the spermatozoa, in different regions of the epididymis. In general, the enzymes involved in active transport showed strongest reactions in the initial and terminal segments, the reactions in the stereocilia being the most intense. The enzymes involved in energy metabolism showed strongest reactions in the middle and terminal segments, with the activity being fairly evenly distributed throughout the cytoplasm of the principal cells. However, the two lysosomal enzymes which were studied showed quite different distributions: the reactions for acid phosphatase were strongest in the initial and middle segments, whilst the reactions for non-specific esterase were strongest in the middle and terminal segments. It is suggested that the initial segment is involved in absorptive and anabolic activity, the middle segment in anabolic activity, and the terminal segment (where spermatozoa are stored ready for ejaculation) in considerable metabolic activity and active transport of substrates across the epithelium.
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PMID:Studies of the deferent ducts from the testis of the African elephant, Loxodonta africana. II. Histochemistry of the epididymis. 644 36

Rabbit sperm pyruvate kinase remains bound to the cell structure of hypotonically treated mature rabbit epididymal spermatozoa (HTRES). It displays kinetic behavior very similar to that of rabbit muscle pyruvate kinase with regard to KM values for substrates, activation by monovalent and divalent cations, inhibition by phenylalanine which is reversed by alanine, and lack of activation by fructose-1,6-biphosphate. The flagellar ATPase also remains bound to the cell structure of HTRES, whose motility may be reactivated by a source of ATP. It requires Mg+2 for activity; the KM for both ATP and MG+2 is 0.2 mM, implying that MgATP is the substrate. The ATPase activity is not inhibited by ouabain, oligomycin, or vanadate, which also do not affect reconstituted motility, and is not affected by cyclic AMP in the presence of an inhibitor of phosphodiesterase. The activities of pyruvate kinase and the flagellar ATPase in a given preparation of HTRES are comparable. Rabbit spermatozoa have a metabolic strategy which is very similar to muscle cells. This suggests that the major use of the sperm cell's metabolic machinery is maintenance of energy for the contractile work of motility and that only minor amounts of metabolic energy appear to be consumed in other reactions, including those involved in fertilization.
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PMID:Properties of pyruvate kinase and flagellar ATPase in rabbit spermatozoa: relation to metabolic strategy of the sperm cell. 644 94


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