{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,9,19]],"date-time":"2025-09-19T11:25:10Z","timestamp":1758281110733},"reference-count":0,"publisher":"Portland Press Ltd.","issue":"2","content-domain":{"domain":["portlandpress.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[1974,8,15]]},"abstract":"<jats:p>1. Guanylate cyclase activity was determined in homogenates of guinea-pig islets of Langerhans by measurement of the conversion of [\u03b1-32P]GTP into cyclic [32P]GMP, the reaction products being separated on columns of neutral alumina. 2. The pH optimum of the enzyme was 7.3; it showed a requirement for bivalent cations, the effectiveness of the cations tested being Mn2+\u00bbCa2+&amp;gt;Mg2+. 3. About 70% of enzyme activity was sedimented by centrifugation at 105000g for 60min; activity was increased 2.3-fold by treatment of homogenates with 0.1% Triton X-100. 4. Guanylate cyclase activity of homogenates was increased by acetylcholine, secretin or pancreozymin, but was inhibited by adrenaline, noradrenaline or ATP. Insulin, glucagon, prostaglandins E1 or E2, glucose, F-, diazoxide or glibenclamide were ineffective. 5. Determination of cyclic GMP amounts in islets by radioimmunoassay showed a basal concentration of 2.0pmol\/mg of protein, which was increased by incubation of the islets in the presence of acetylcholine or the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine, but was unaffected by glucose. 6. Dibutyryl cyclic GMP had significant stimulatory effects on rates of insulin biosynthesis in isolated rat islets of Langerhans. 7. These results suggest a possible role for cyclic GMP in the regulation of insulin biosynthesis and secretion.<\/jats:p>","DOI":"10.1042\/bj1420379","type":"journal-article","created":{"date-parts":[[2015,8,10]],"date-time":"2015-08-10T19:54:43Z","timestamp":1439236483000},"page":"379-384","update-policy":"http:\/\/dx.doi.org\/10.1042\/crossmark_policy","source":"Crossref","is-referenced-by-count":35,"title":["Regulation of guanylate cyclase in guinea-pig islets of Langerhans"],"prefix":"10.1042","volume":"142","author":[{"given":"Simon L.","family":"Howell","sequence":"first","affiliation":[{"name":"School of Biological Sciences, University of Sussex, Falmer, Brighton BN1 9QG, Sussex, U.K."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"William","family":"Montague","sequence":"additional","affiliation":[{"name":"King's College Hospital Medical School, Denmark Hill, London SE5 8RX, U.K."}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"288","container-title":["Biochemical Journal"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/142\/2\/379\/781198\/bj1420379.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/142\/2\/379\/781198\/bj1420379.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,11,26]],"date-time":"2021-11-26T16:29:15Z","timestamp":1637944155000},"score":1,"resource":{"primary":{"URL":"https:\/\/portlandpress.com\/biochemj\/article\/142\/2\/379\/9677\/Regulation-of-guanylate-cyclase-in-guinea-pig"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1974,8,15]]},"references-count":0,"journal-issue":{"issue":"2","published-print":{"date-parts":[[1974,8,15]]}},"URL":"https:\/\/doi.org\/10.1042\/bj1420379","relation":{},"ISSN":["0306-3283"],"issn-type":[{"value":"0306-3283","type":"print"}],"subject":[],"published":{"date-parts":[[1974,8,15]]}}}