{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,4]],"date-time":"2026-05-04T12:30:03Z","timestamp":1777897803302,"version":"3.51.4"},"reference-count":0,"publisher":"S. Karger AG","license":[{"start":{"date-parts":[[2008,11,25]],"date-time":"2008-11-25T00:00:00Z","timestamp":1227571200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/karger.com\/pages\/terms-and-conditions"},{"start":{"date-parts":[[2008,11,25]],"date-time":"2008-11-25T00:00:00Z","timestamp":1227571200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/karger.com\/pages\/terms-and-conditions"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Horm Res"],"abstract":"<jats:p>Endocrine and behavioral effects of age and aging have been studied in 4 groups of Sprague-Dawley male rats (2, 6, 12, 24 months old). Plasma testosterone decreases after 6 months of age, plasma estradiol decreases from 2 to 6 months, then it increases with age and decreases again with aging (from 12 to 24 months). Aromatization of testosterone in brain tissue is similar in 2-, 12- and 24-month-old rats, but at 6 months a significant increase is observed. Testosterone biosynthesized in the gonad from dehydroepiandrosterone increases from 2 to 6 months, then it decreases, while the other metabolites of dehydroepiandrosterone show an increment with age. Corticosterone and 17\u03b1-hydroxyprogesterone biosynthesized in the adrenal decrease with aging. Explorative and loco-motor activity decreases with age and aging, while emotionality decreases from 2 to 12 months, but it increases with aging. These results indicate that endocrine equilibrium is remarkably altered by aging process showing a decrease of plasma sexual hormones and of gonadal activity. The decrement of aromatization of testosterone in the brain, which occurs between 6 and 12 months, is correlated with the decrement of plasma testosterone. It could be hypothesized that the hormones of the brain-pituitary-gonad axis are involved in the control of explorative behavior or that both hormonal and behavioral parameters are controlled by a common factor.<\/jats:p>","DOI":"10.1159\/000179116","type":"journal-article","created":{"date-parts":[[2008,11,29]],"date-time":"2008-11-29T09:18:13Z","timestamp":1227950293000},"page":"149-160","source":"Crossref","is-referenced-by-count":17,"title":["Endocrine and Behavioral Modifications in Aging Male Rats"],"prefix":"10.1159","author":[{"given":"Concetta","family":"Lupo-di Prisco","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Francesco","family":"Dessi-Fulgheri","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"127","published-online":{"date-parts":[[2008,11,25]]},"container-title":["Hormone Research"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/karger.com\/article-pdf\/doi\/10.1159\/000179116","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T09:12:26Z","timestamp":1777626746000},"score":1,"resource":{"primary":{"URL":"https:\/\/karger.com\/article\/doi\/10.1159\/000179116"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2008,11,25]]},"references-count":0,"URL":"https:\/\/doi.org\/10.1159\/000179116","archive":["Portico"],"relation":{},"ISSN":["0301-0163","1423-0046"],"issn-type":[{"value":"0301-0163","type":"print"},{"value":"1423-0046","type":"electronic"}],"subject":[],"published":{"date-parts":[[2008,11,25]]}}}