Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0406810 (NAME)
 13,345 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Endogenous nitric oxide (NO) is an important functional mediator in several physiological systems, including the reproductive system. However, when generated in excessive amounts for long periods, mainly during immunological reactions, NO is cytotoxic and cytostatic for invading microbes, as well as for the cells generating it and the tissues present around it. Since infertility associated with urogenital tract infection in males and females is also accompanied by reduced sperm motility and viability, it is possible that reduced fertility in these patients is due to NO-induced sperm toxicity. We therefore evaluated the direct effects of NO, chemically derived from S-nitroso-N-acetylpenicillamine (SNAP, 0.012-0.6 mM) and sodium nitroprusside (SNP, 0.25-2.5 mM), on the motility and viability of human spermatozoa. Furthermore, we tested whether inhibition of NO synthesis prevents sperm motility and viability by incubating washed total cells present in the semen (spermatozoa, round cells) with N-nitro-L-arginine-methyl-ester (L-NAME), a NO synthesis inhibitor. Treatment of purified spermatozoa with SNAP or SNP decreased forward progressive sperm motility and straight line velocity, and also increased the percentage of immotile spermatozoa in a concentration-dependent manner. Furthermore, the percentage of immotile spermatozoa positively correlated with the percentage of dead spermatozoa. In contrast to freshly prepared SNAP, SNAP preincubated for 48 h had no effect on the motility and viability of the spermatozoa. Furthermore, as compared to untreated controls, a significantly higher percentage of forward progressive sperm motility as well as viability (P < 0.05) was maintained in washed semen incubated with L-NAME (0.15 mM).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effects of nitric oxide on human spermatozoa: evidence that nitric oxide decreases sperm motility and induces sperm toxicity. 858 80

The techniques of assisted reproduction have recently become the most effective methods of treatment of infertility; namely ICSI (intra-cytoplasmic sperm injection), MESA (microepididymal sperm aspiration), TESA (testicular sperm aspiration) and TESE (testicular sperm extraction). The techniques have been increasingly successful, even above the average efficiency of classical IVF (in vitro fertilization). It can be demonstrated by the percentage of ICSI-aided births percentage per 100% of embryotransfers in ISCARE; 1996 = 21.3%, 1997 = 26.15%, 1998 = 29.7%. The successful use of these techniques is associated with the rise of risks which result from the selection of couples for assisted reproduction with genetic-based infertility and with the rise of risks involving the introduction of genetic-based defects in to the next generation. Presently, a list of indications is being developed, which, while still not accepted officially, identifies patients for genetic counselling. Only the counselling center has the competence to estimate genetic risks over generations. Subsequently, after selection by the center, during 1997 and 1998 the chromosomes of 731 patients were cytogenetically examined, representing 429 infertile couples from the centres ISCARE, PRONATAL, FERTIMED, and CAR 1. LF UK. Within these 429 couples, belonging to four groups of indications, the cytogenetic examination was informative in 8.15%. This finding of a relatively high percentage (10 times more than in the general population) confirms the validity of the list of indications and the necessity of cooperation among the genetic counselling center, cytogenetic laboratory and the IVF centre.
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PMID:[Cooperation between genetic counseling centers, cytogenetic laboratories and in vitro fertilization centers in the treatment of reproductive disorders]. 1091 14

Carney complex (CNC) is a multiple neoplasia syndrome characterised by endocrine tumours, spotty skin pigmentation, cardiac and other myxomas, psamommatous and pigmented schwannomas, large cell calcifying Sertoli cell tumours, and mammary ductal adenomas and other more rare lesions. CNC is inherited in an autosomal-dominant manner and has been mapped to at least two chromosomal loci. Patients who map to the CNC1 locus located on chromosome 17 carry inactivating mutations of the PRKAR1A gene that encodes the cAMP-dependent protein kinase regulatory subunit type 1-alpha (Kirschner et al., 2000). One gene responsible for type 2 (CNC2) is located on chromosome 2p16. Infertility in CNC can be caused by a number of factors; there is evidence that prkar1a deficiency in mice leads directly to infertility (Burton et al., 2006), but patients with CNC also have Sertoli cell tumours and a number of other reasons to affect fertility. We report on an infertile male with CNC and present evidence that male infertility should be considered as part of the phenotype of CNC.
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PMID:Male infertility as a component of Carney complex. 1771 19

Deteriorating oocyte quality is a critical hurdle in the management of infertility, especially one associated with advancing age. In this study, we explore the role of nitric oxide (NO) on the sustenance of oocyte quality postovulation. Sibling oocytes from superovulated mice were subjected to intracytoplasmic sperm injection (ICSI) with cauda-epididymal spermatozoa following exposure to either the NO donor, S-nitroso-N-acetylpenicillamine (SNAP, 0.23 microM/min), an NO synthase (NOS) inhibitor, N omega-nitro-L-arginine methyl ester (L-NAME, 1 mM), or an inhibitor of soluble guanylyl cyclase (sGC), 1H-[1,2,4] oxadiazolo [4,3-a] quinoxalin-1-one (ODQ, 100 microM); while their sibling oocytes were subjected to ICSI either before (young) or after culture for the corresponding period of time (old). Outcomes of normal fertilization, cleavage, and development to the morula and blastocyst stages were compared. Embryos from each subgroup were also subjected to TUNEL assay for apoptosis. A significant deterioration in the ability of the oocytes to undergo normal fertilization and development to morula and blastocyst stages occurred among oocytes aged in culture medium compared to their sibling cohorts subjected to ICSI immediately after ovulation (P<0.05). This deterioration was prevented in oocytes exposed to SNAP. In contrast, exposure to L-NAME or ODQ resulted in a significant compromise in fertilization and development to the morula and blastocyst stages (P<0.05). Finally, apoptosis was noted in embryos derived from aged oocytes and those exposed to L-NAME or ODQ, but not in embryos derived from young oocytes or oocytes exposed to SNAP. Thus, NO is essential for sustenance of oocyte quality postovulation.
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PMID:Nitric oxide extends the oocyte temporal window for optimal fertilization. 1848 13