{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,4]],"date-time":"2026-10-04T16:02:46Z","timestamp":1791129766574,"version":"4.1.0"},"reference-count":0,"publisher":"Oxford University Press (OUP)","content-domain":{"domain":["eje.bioscientifica.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2003,8,1]]},"abstract":"<jats:p>OBJECTIVE: It has been gradually realized that GH may have important physiological functions in adult humans. The biochemical diagnosis of adult GHD is established by provocative testing of GH secretion. The insulin-tolerance test (ITT) is the best validated. The ITT has been challenged because of its low degree of reproducibility and lack of normal range, and is contra-indicated in common clinical situations. Furthermore, in severely obese subjects the response to the ITT frequently overlaps with those found in non-obese adult patients with GHD. DESIGN: The aim of the present study was to evaluate the diagnostic capability of four different stimuli of GH secretion: ITT, GHRH, GHRH plus acipimox (GHRH+Ac), and GHRH plus GHRP-6 (GHRH+GHRP-6), in two pathophysiological situations: hypopituitarism and obesity, and normal subjects. METHODS: Eight adults with hypopituitarism (four female, four male) aged 41-62 Years (48.8+\/-1.4 Years), ten obese normal patients (five female, five male) aged 38-62 Years (48.1+\/-2.5 Years), with a body mass index of 34.2+\/-1.2 kg\/m(2), and ten normal subjects (five female, five male) aged 33-62 Years (48.1+\/-2.8 Years) were studied. Four tests were performed on each patient or normal subject: An ITT (0.1 U\/kg, 0.15 U\/kg for obese, i.v., 0 min), GHRH (100 microg, i.v., 0 min), GHRH (100 microg, i.v., 0 min) preceded by acipimox (250 mg, orally, at -270 min and -60 min) (GHRH+Ac); and GHRH (100 microg, i.v., 0 min) plus GHRP-6 (100 microg, i.v., 0 min) (GHRH+GHRP-6). Serum GH was measured by radioimmunoassay. Statistical analyses were performed by Wilcoxon rank sum and by Mann-Whitney tests. RESULTS: After the ITT the mean peak GH secretion was 1.5+\/-0.3 microg\/l for hypopituitary, 10.1+\/-1.7 microg\/l (P&lt;0.05 vs hypopituitary) for obese and 17.8+\/-2.0 microg\/l (P&lt;0.05 vs hypopituitary) for normal. GHRH-induced GH secretion was 2+\/-0.7 microg\/l for hypopituitary, 3.9+\/-1.2 microg\/l (P=NS vs hypopituitary) for obese and 22.2+\/-3.8 microg\/l (P&lt;0.05 vs hypopituitary) for normal. After GHRH+Ac, mean peak GH secretion was 3.3+\/-1.4 microg\/l for hypopituitary, 14.2+\/-2.7 microg\/l (P&lt;0.05 vs hypopituitary) for obese and 35.1+\/-5.2 microg\/l (P&lt;0.05 vs hypopituitary) for normal. GHRH+GHRP-6 induced mean peak GH secretion of 4.1+\/-0.9 microg\/l for hypopituitary, 38.5+\/-6.5 microg\/l (P&lt;0.05 vs hypopituitary) for obese and 68.1+\/-5.5 microg\/l (P&lt;0.05 vs hypopituitary) for normal subjects. Individually considered, after ITT, GHRH or GHRH+Ac, the maximal response in hypopituitary patients was lower than the minimal response in normal but higher than the minimal response in obese subjects. In contrast, after GHRH+GHRP-6 the maximal response in hypopituitary patients was lower than the minimal response in normal and obese subjects. CONCLUSIONS: This study suggests that, in this group of patients, although both acipimox and GHRP-6 partially reverse the functional hyposomamotropism of obesity after GHRH, but are unable to reverse the organic hyposomatotropism of hypopituitarism, the combined test GHRH+GHRP-6 most accurately distinguishes both situations, without the side effects of ITT.<\/jats:p>","DOI":"10.1530\/eje.0.1490117","type":"journal-article","created":{"date-parts":[[2005,1,24]],"date-time":"2005-01-24T21:34:41Z","timestamp":1106602481000},"page":"117-122","update-policy":"https:\/\/doi.org\/10.1530\/crossmarkpolicy-1","source":"Crossref","is-referenced-by-count":54,"title":["Comparison between insulin tolerance test, growth hormone (GH)-releasing hormone (GHRH), GHRH plus acipimox and GHRH plus GH-releasing peptide-6 for the diagnosis of adult GH deficiency in normal subjects, obese and hypopituitary patients"],"prefix":"10.1093","author":[{"given":"F","family":"Cordido","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"P","family":"Alvarez-Castro","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"ML","family":"Isidro","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"FF","family":"Casanueva","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"C","family":"Dieguez","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","container-title":["European Journal of Endocrinology"],"original-title":[],"link":[{"URL":"https:\/\/eje.bioscientifica.com\/view\/journals\/eje\/149\/2\/117.xml","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/eje.bioscientifica.com\/view\/journals\/eje\/149\/2\/117.xml","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,2,14]],"date-time":"2023-02-14T16:32:35Z","timestamp":1676392355000},"score":1,"resource":{"primary":{"URL":"https:\/\/academic.oup.com\/ejendo\/article\/149\/2\/117\/6753343"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2003,8,1]]},"references-count":0,"URL":"https:\/\/doi.org\/10.1530\/eje.0.1490117","relation":{},"ISSN":["0804-4643","1479-683X"],"issn-type":[{"value":"0804-4643","type":"print"},{"value":"1479-683X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2003,8,1]]}}}