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

Seminal plasma from 22 men attending an infertility clinic was subjected to preparative ultracentrifugation for 2 h at 105,000 g. The pelleted material as well as the supernatant thus obtained were investigated with regard to prostasome membrane-linked enzyme activities in relation to other semen parameters. The mean activity of Zn2+-dependent adenosine triphosphatase in the sedimented prostasome fraction was 1.45 +/- 1.02 mumol (range 0.29-4.79) orthophosphate released per milligram protein and 20 min, while the corresponding figures for the supernatant were 0.56 +/- 0.30 (range 0.12-1.29). Hence, 72% of the specific activity was sedimented, and 28% remained in the supernatant. The same pattern was recognized with regard to the other two enzymes investigated, although they displayed individual characteristics with regard to distribution after ultracentrifugation. The pelleted prostasome-linked mean aminopeptidase activity was 0.39 U/mg protein (81.9%), with only 0.087 U (18.1%) remaining in the supernatant. The corresponding figures for gamma-glutamyltransferase were 7.89 (60.4%) and 5.17 (39.6%) mu kat/g protein, respectively. The different enzyme activities in the prostasome fraction and supernatant, respectively, were interrelated to each other and correlated significantly with r values between 0.73 and 0.93 (p less than 0.001). It was concluded that a minor fraction of prostasomes remained in the supernatant after ultracentrifugation. A relationship existed between prostasomes and semen volume revealing a rather consistent pattern in that small volumes favoured the presence of comparatively more prostasomes in the supernatant and less prostasomes in the pelleted fraction than large volumes. In addition, the sperm concentration seemed to be another determinant of the distribution of prostasomes in seminal plasma on subsequent ultracentrifugation.
 ...
PMID:Prostasome membrane associated enzyme activities and semen parameters in men attending an infertility clinic. 290 7

A pronounced deficiency of Mg2+ and Ca2+-dependent ATPase and of secretory granules and vesicles was demonstrated in the seminal plasma of a patient with infertility problems (person A) and with a lowered serum testosterone level. Both total ejaculates and different fractions of split-ejaculates were examined on repeated occasions. Divalent cations, fructose and protein were also determined in most of the samples. The low activity of the Mg2+ and Ca2+-dependent ATPase and the ultrastructure of the split-ejaculates of the seminal plasma of person A contrasted sharply against the high activity of the Mg2+ and Ca2+-dependent ATPase and the ultrastructure of the split-ejaculates of the seminal plasma of another individual (person B). The latter displayed a normal Mg2+ and Ca2+-dependent ATPase activity as well as an ordinary representation of the secretory granules and vesicles. The findings on the ATPase system in the seminal plasma of person A together with the lowered levels of divalent cations in the order Ca2+ less than Mg2+ less than Zn2+ are proposed to reflect a defective functioning of the prostate gland in person A.
 ...
PMID:Abnormal deficiency of both Mg2+ and Ca2+-dependent adenosine triphosphatase and secretory granules and vesicles in human seminal plasma. 612 May 66

Motility of sperm flagella as well as of cilia is mechanically based on the principle of 9 + 2-tubules. It functions essentially by coordinated action between microtubules and the adenosine-triphosphatase dynein and was already present at the beginning of the evolution of the eucaryotes. Experimentally induced mutations in algae have resulted in numerous variations of the flagellar 9 + 2-structure. A mutation of this kind is also found in man, as immotile cilia syndrome (ICS) where anomalies in spermatozoa and in cilia (e.g. of the respiratory tract) are observed. Clinical manifestations of the syndrome have long been known (chronic bronchitis, bronchiectasis, sinusitis and male sterility). In addition, half of the patients exhibit situs inversus viscerum, known as Kartagener's syndrome, a subgroup of ICS. Electron microscopy was used to investigate sperm flagella with reduced motility from 9 patients (one with ICS) with primary infertility. Cilia of the respiratory tract from 7 patients (several with ICS) with chronic bronchial problems were analyzed for motility (using video techniques) and ultrastructure. Reduced motility or immotility of spermatozoa and immotile or dyskinetic cilia were always accompanied by ultrastructural anomalies. In spermatozoa, lack of dynein arms, 9 + 0-configuration and extratubuli were most frequently observed. The fibrous sheath was always asymmetrical. Structural ciliary defects resulted in non-parallel arrangements, electron dense matrix substance, extratubuli and lack of radial spokes. In one case, ciliary microtubuli were found in microvilli. In two patients, cilia as well as spermatozoa were analyzed. In the first, immotile spermatozoa without dynein arms and structurally normal cilia were observed.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:[Sperm flagella and cilia with pathologic motility and ultrastructure]. 650 61

The present study was performed to further clarify the influences of vasectomy on functions of testis and to disclose the possible mechanisms of infertility after vasovasostomy (VV). Thirty-one rabbits were divided into sham-operated control group (C), vasectomy control group (V), VV fertility group (VaF) and VV infertility group (VaI). Serum testosterone (ST) level, testicular cAMP, androgen binding protein (ABP), nuclear androgen receptor (NAR) concentrations, testis cell membrane Na(+)-, K(+)-ATPase, Mg(2+)-ATPase activities, sperm density and testis weight were measured. Vasectomy resulted in significantly reduced cAMP, Na(+)-, K(+)-ATPase, Mg(2+)-ATPase, testis weight and increased ABP; VV completely restore testis weight in VaF and VaI, Na(+)-, K(+)-ATPase, Mg(2+)-ATPase in VaF, partly cAMP in VaF and VaI, Na(+)-, K(+)-ATPase, Mg(2+)-ATPase in VaI, but did not restore ABP. The NAR content in VaI was significantly lower than those in C, VaF and V. No statistical differences among 4 groups were seen in Kd values for [3H]-T. ST levels in VaF, VaI and V were insignificantly different compared with C, but the value in VaF was higher than that in VaI (p < 0.05). Sperm density after VV reached 122 +/- 62 x 10(6)/ml in VaF and 10 +/- 24 x 10(6)/ml in VaI, both in VaF and VaI were significantly low compared with C (p < 0.001), and the value in VaI was remarkedly lower than that in VaF (p < 0.001). It was shown that sperm density was positively correlated with cAMP content, Na(+)-, K(+)-ATPase, Mg(2+)-ATPase activities, but negatively with ABP. These results suggest that vasectomy gives rise to damage to the testis, and vasovasostomy does not appear completely effective in reversing testicular changes.
 ...
PMID:The influence of vasectomy and vasovasostomy on testicular ATPases, cAMP, ABP and androgen receptor in rabbits. 785 57

An acidic luminal pH (ref. 1-3) is involved in sperm maturation, and in maintaining sperm in an immotile state in the epididymis and vas deferens (2,4-6). Neutralization by prostatic fluid is one of a complex series of events that triggers sperm motility (2,7,8). Failure of the acidification mechanism might, therefore, result in poor sperm maturation, premature motility and infertility. We have shown that a vacuolar (H+)-ATPase is expressed at high levels on the luminal plasma membrane of specialized cells in the epididymis (9), which closely resemble acid-secreting kidney intercalated cells (10,11). We now show that similar cells are also present in the vas deferens, and that a bafilomycin-sensitive proton flux can be detected using a noninvasive proton-selective vibrating probe. Up to 80% of the net proton secretion in the vas deferens is inhibited by bafilomycin, consistent with a major role of a vacuolar-type (H+)-ATPase in this process. This acidification mechanism is a potential target for novel strategies aimed at modulating the acidification capacity of parts of the male reproductive tract and, therefore, in regulating male fertility.
 ...
PMID:Acidification of the male reproductive tract by a proton pumping (H+)-ATPase. 859 61

Styrene is an important industrial chemical that is extensively used in the production of resins, rubbers and fiberglass-reinforced plastics. Exposing male rats to high doses of styrene may produce sperm abnormalities or infertility. To determine the mechanism underlying styrene-mediated toxicity in male reproductive organs, a reverse transcription-polymerase chain reaction (RT-PCR) technology was employed using annealing control primers (ACPs) to identify the differentially expressed genes following styrene treatment in isolated testis of male rats. By using 120 ACPs, a total of 6 expressed sequence tags (ESTs) of genes were differentially expressed in styrene-treated rats, as compared to untreated, which were cloned and sequenced. Of the genes analyzed, 5 genes (testis-specific expressed gene 101, protein kinase C, H+-ATPase isoform 2, peroxiredoxin 1, and aquaporin 9) were inducible and one gene expression (clusterin) was significantly suppressed by styrene. Regulation of each gene by styrene was confirmed by RT-PCR. It was shown that styrene decreased clusterin expression in a concentration-dependent manner and these effects occurred mainly in testis. Taken together, these results indicate that repression of clusterin gene expression by styrene may play an important role in styrene-mediated toxicities.
 ...
PMID:Differential gene expression by styrene in rat reproductive tissue. 1765 43

The 26S proteasome is an essential multicatalytic protease complex that degrades a wide range of intracellular proteins, especially those modified with ubiquitin. Arabidopsis thaliana and other plants use pairs of genes to encode most of the core subunits, with both of the isoforms often incorporated into the mature complex. Here, we show that the gene pair encoding the regulatory particle non-ATPase subunit (RPN5) has a unique role in proteasome function and Arabidopsis development. Homozygous rpn5a rpn5b mutants could not be generated due to a defect in male gametogenesis. While single rpn5b mutants appear wild-type, single rpn5a mutants display a host of morphogenic defects, including abnormal embryogenesis, partially deetiolated development in the dark, a severely dwarfed phenotype when grown in the light, and infertility. Proteasome complexes missing RPN5a are less stable in vitro, suggesting that some of the rpn5a defects are caused by altered complex integrity. The rpn5a phenotype could be rescued by expression of either RPN5a or RPN5b, indicating functional redundancy. However, abnormal phenotypes generated by overexpression implied that paralog-specific functions also exist. Collectively, the data point to a specific role for RPN5 in the plant 26S proteasome and suggest that its two paralogous genes in Arabidopsis have both redundant and unique roles in development.
 ...
PMID:The RPN5 subunit of the 26s proteasome is essential for gametogenesis, sporophyte development, and complex assembly in Arabidopsis. 1925 82

Physiological function of reactive oxygen species (ROS) has been known since a long, but recently toxic effects of ROS on spermatozoa have gained much importance in male infertility. Mitochondrial DNA (mtDNA) is believed to be both source and target of ROS. mtDNA unlike nuclear DNA is not compactly packed and hence more susceptible to oxidative stress (OS) than nuclear DNA. In the present study, the role of OS in mitochondrial genome changes was studied in men with idiopathic infertility. The study included 33 infertile oligo-asthenozoospermic (OA) men and 30 fertile controls. Semen analyses were performed and OS was measured by estimating the level of malondialdehye (MDA) in the seminal plasma and ROS in the sperm. Sperm mtDNA was sequenced by standard PCR-DNA sequencing protocol for ATPase and nicotinamide adenine dinucleotide dehydrogenase (ND) groups of genes. Sperm count and progressive motility were found to be significantly lower in infertile group than the fertile controls. Semen MDA and ROS levels of infertile group were significantly higher (p<0.0001), when compared to the control group. However, catalase and glutathione peroxidase (GPx) levels were significantly lower in infertile group, compared to controls, but no significant difference in superoxide dismutase (SOD) activity was observed between control and cases. This might be due to higher expression of SOD alone in order to overcome OS in the semen. mtDNA analysis showed significant and high frequency of nucleotide changes in the ATPase (6 and 8), ND (2, 3, 4 and 5) genes of infertile cases compared to the controls. Hence excess ROS and low antioxidant levels in the semen might cause mtDNA mutations and vice versa in OA men that might impair the fertilizing capacity of spermatozoa. Thus, it is important to understand the etiology of mitochondrial genome mutations in idiopathic OA cases for better diagnostic and prognostic value in infertility treatment/assisted reproductive technique.
 ...
PMID:Oxidative stress and sperm mitochondrial DNA mutation in idiopathic oligoasthenozoospermic men. 1951 95

Sertoli cells play a key role in the establishment of an adequate luminal environment in the seminiferous tubules of the male reproductive tract. Secretion of the seminiferous tubular fluid (STF) is vital for the normal occurrence of spermatogenesis and for providing a means of transport to the developing spermatozoa. However, several studies on this subject have not completely clarified the origin and composition of this fluid. Electrolyte and water are central components of STF. Sertoli cells secrete an iso-osmotic fluid with a higher content of K(+) than the blood and express various membrane and water transporters (Na(+)/K(+)-ATPase; Ca(2+)-ATPase; V-type ATPase; Cl(-) channels; CFTR Cl(-) channels; K(+) channels; L-, T- and N-type Ca(2+) channels; Na(+)/H(+) exchangers; Na(+)-driven HCO(3) (-)/Cl(-) exchangers (NDCBEs); Na(+)/HCO(3) (-) cotransporters (NBCes); Na(+)-K(+)-2Cl(-) cotransporter; Na(+)/Ca(2+) exchanger; and aquaporins 0 and 8) involved in cellular and secretory functions. Studies with knockout mice for some of these transporters showed tubular fluid accumulation and associated infertility, revealing the relevance of these processes for the normal occurrence of spermatogenesis. Nevertheless, the role of the several membrane transporters in the establishment of STF electrolyte composition needs to be further elucidated. This review summarizes the available data on the ionic composition of STF and on the Sertoli cell membrane mechanisms responsible for ion and water movement. Deepening the knowledge on the mechanisms involved in the secretion, composition and regulation of SFT is essential and will be a major step in understanding the infertility associated with some pathological conditions.
 ...
PMID:Tubular fluid secretion in the seminiferous epithelium: ion transporters and aquaporins in Sertoli cells. 2069 86

1. Male fertility is a complex process that is dependent on sex hormones and the normal function of the reproductive organs. Defects of these organs result in abnormal sperm production and function, which, in turn, lead to infertility. 2. Spermatozoa released from the testis are unable to move and fertilize with eggs. These features, known as sperm maturation, are acquired during their transit through the epididymis. 3. Among several processes that take place in the epididymis, absorption and acidification of the luminal fluid are essential for sperm maturation, sperm storage and fertility. Currently, the mechanism by which acidification occurs in the epididymis is still not fully understood. 4. The epididymis is fully equipped with the proteins required for acid/base transport, such as Na(+) /H(+) exchanger 3 (NHE3, SLC9A3), vacuolar-type adenosine triphosphatase (V-ATPase) and various isoforms of enzyme carbonic anhydrase (CA). 5. Most studies, so far, have focused on the role of V-ATPase on H(+) secretion and acidification of the epididymis. The involvement of NHE3 in creating the acidic environment of the epididymal spermatozoa receives little attention. 6. This review presents evidence for and discusses the role of NHE3 in the acidification of the male reproductive tract and its requirement for male fertility.
 ...
PMID:Role of Na+ /H+ exchanger 3 in the acidification of the male reproductive tract and male fertility. 2148 Sep 44


1 2 3 4 Next >>