{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,7]],"date-time":"2026-09-07T13:51:39Z","timestamp":1788789099382,"version":"build-2803163510"},"reference-count":33,"publisher":"Wiley","issue":"5","license":[{"start":{"date-parts":[[2006,3,24]],"date-time":"2006-03-24T00:00:00Z","timestamp":1143158400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J Neuroendocrinology"],"published-print":{"date-parts":[[2006,5]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:p>Siberian hamsters (<jats:italic>Phodopus sungorus<\/jats:italic>) undergo reproductive involution following exposure to short winter day lengths. Following approximately 20\u2003weeks of exposure to short day (SD) lengths, hamsters become refractory to the inhibitory effects of SD, and reproductive competence is restored in anticipation of spring. The extent to which changes in gonadal steroid\u2010dependent and \u2010independent regulation of gonadotrophin secretion participate in this vernal reactivation of the gonads is not known. This experiment tested whether tonic and gonadotrophin\u2010releasing hormone (GnRH)\u2010stimulated regulation of lutenising hormone (LH) secretion differs between photoresponsive and photorefractory Siberian hamsters. Male hamsters born into long day (LD) lengths were castrated or subjected to a sham\u2010castration surgery at 17\u2003days of age, implanted s.c. with blank or testosterone\u2010filled capsules, and housed in LD or SD thereafter. Baseline LH and LH responses to GnRH (200\u2003ng\/kg, s.c) were measured at 14 (photoresponsive) and 40 (photorefractory)\u2003weeks of age. Despite lower circulating testosterone concentrations in gonadally regressed SD hamsters on week 14, tonic LH concentrations were comparable among all groups of gonad\u2010intact hamsters on weeks 14 and 40; however, week 14 SD hamsters exhibited significantly higher GnRH\u2010stimulated LH responses. Tonic LH concentrations were indistinguishable among all groups of castrated hamsters bearing empty implants on week 14, but prolonged exposure to LD led to a decrease in resting LH, whereas prolonged exposure to SD resulted in an increase in LH. In castrated hamsters bearing testosterone implants, baseline LH concentrations were comparable in all groups, but GnRH treatment resulted in significantly higher LH concentrations in photorefractory (week 40, SD) hamsters relative to all other groups. The data suggest that the development of photorefractoriness in Siberian hamsters is characterised by enhanced gonadal hormone\u2010independent stimulation of LH secretion, and diminished sensitivity to inhibitory negative\u2010feedback effects of testosterone on LH secretion. Decreases in responsiveness of gonadotrophin secretion to gonadal hormone negative feedback may contribute to the process of photorefractoriness and assist in maintaining the growth of reproductive organs during the process of gonadal recrudescence.<\/jats:p>","DOI":"10.1111\/j.1365-2826.2006.01419.x","type":"journal-article","created":{"date-parts":[[2006,3,24]],"date-time":"2006-03-24T14:01:02Z","timestamp":1143208862000},"page":"339-348","source":"Crossref","is-referenced-by-count":8,"title":["Refractoriness to Short Day Lengths Augments Tonic and Gonadotrophin\u2010Releasing Hormone\u2010Stimulated Lutenising Hormone Secretion"],"prefix":"10.1111","volume":"18","author":[{"given":"B. J.","family":"Prendergast","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"A. K.","family":"Hotchkiss","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J.","family":"Wen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"T. H.","family":"Horton","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"R. J.","family":"Nelson","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2006,3,24]]},"reference":[{"key":"e_1_2_6_2_2","first-page":"451","volume-title":"Behavioral Endocrinology","author":"Gorman MR","year":"2002"},{"key":"e_1_2_6_3_2","doi-asserted-by":"publisher","DOI":"10.1016\/B978-012532104-4\/50021-4"},{"key":"e_1_2_6_4_2","doi-asserted-by":"publisher","DOI":"10.1095\/biolreprod28.1.178"},{"key":"e_1_2_6_5_2","doi-asserted-by":"publisher","DOI":"10.1002\/jez.1402560444"},{"key":"e_1_2_6_6_2","doi-asserted-by":"publisher","DOI":"10.1095\/biolreprod13.4.475"},{"key":"e_1_2_6_7_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0079-6123(08)62946-5"},{"key":"e_1_2_6_8_2","doi-asserted-by":"publisher","DOI":"10.1007\/978-3-642-68651-1_33"},{"key":"e_1_2_6_9_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0031-9384(96)80027-8"},{"key":"e_1_2_6_10_2","doi-asserted-by":"publisher","DOI":"10.1007\/978-1-4612-3740-2_11"},{"key":"e_1_2_6_11_2","doi-asserted-by":"publisher","DOI":"10.1046\/j.1365-2826.2003.00966.x"},{"key":"e_1_2_6_12_2","doi-asserted-by":"publisher","DOI":"10.1177\/074873048800300208"},{"key":"e_1_2_6_13_2","volume-title":"The Suprachiasmatic Nucleus: The Mind's Clock","author":"Zucker I","year":"1991"},{"key":"e_1_2_6_14_2","doi-asserted-by":"publisher","DOI":"10.1126\/science.568311"},{"key":"e_1_2_6_15_2","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.111140398"},{"key":"e_1_2_6_16_2","doi-asserted-by":"publisher","DOI":"10.1159\/000123181"},{"key":"e_1_2_6_17_2","doi-asserted-by":"publisher","DOI":"10.1210\/endo-104-3-631"},{"key":"e_1_2_6_18_2","doi-asserted-by":"publisher","DOI":"10.1095\/biolreprod20.4.739"},{"key":"e_1_2_6_19_2","doi-asserted-by":"publisher","DOI":"10.1006\/hbeh.2000.1604"},{"key":"e_1_2_6_20_2","doi-asserted-by":"publisher","DOI":"10.1152\/ajpregu.1995.269.4.R800"},{"key":"e_1_2_6_21_2","first-page":"184","article-title":"Cortisol and prolactin concentrations during repeated blood sample collection from freely moving, mouse\u2010sized mammals (Phodopus spp.)","volume":"50","author":"Reburn CJ","year":"2000","journal-title":"Comp Med"},{"key":"e_1_2_6_22_2","doi-asserted-by":"publisher","DOI":"10.1677\/joe.0.0980079"},{"key":"e_1_2_6_23_2","doi-asserted-by":"publisher","DOI":"10.1071\/RD99032"},{"key":"e_1_2_6_24_2","doi-asserted-by":"publisher","DOI":"10.3181\/00379727-187-42692"},{"key":"e_1_2_6_25_2","doi-asserted-by":"publisher","DOI":"10.1095\/biolreprod.103.019380"},{"key":"e_1_2_6_26_2","doi-asserted-by":"publisher","DOI":"10.1210\/endo.143.6.8839"},{"key":"e_1_2_6_27_2","doi-asserted-by":"publisher","DOI":"10.1095\/biolreprod59.4.813"},{"key":"e_1_2_6_28_2","doi-asserted-by":"publisher","DOI":"10.1095\/biolreprod53.3.724"},{"key":"e_1_2_6_29_2","doi-asserted-by":"publisher","DOI":"10.1210\/endo-122-3-1060"},{"key":"e_1_2_6_30_2","doi-asserted-by":"publisher","DOI":"10.1530\/jrf.0.0660243"},{"key":"e_1_2_6_31_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.yhbeh.2003.11.001"},{"key":"e_1_2_6_32_2","doi-asserted-by":"publisher","DOI":"10.1095\/biolreprod21.4.801"},{"key":"e_1_2_6_33_2","doi-asserted-by":"publisher","DOI":"10.1159\/000054424"},{"key":"e_1_2_6_34_2","doi-asserted-by":"publisher","DOI":"10.1016\/0006-8993(92)90172-6"}],"container-title":["Journal of Neuroendocrinology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1111%2Fj.1365-2826.2006.01419.x","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1111\/j.1365-2826.2006.01419.x","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,10,12]],"date-time":"2023-10-12T22:31:49Z","timestamp":1697149909000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1111\/j.1365-2826.2006.01419.x"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2006,3,24]]},"references-count":33,"journal-issue":{"issue":"5","published-print":{"date-parts":[[2006,5]]}},"alternative-id":["10.1111\/j.1365-2826.2006.01419.x"],"URL":"https:\/\/doi.org\/10.1111\/j.1365-2826.2006.01419.x","archive":["Portico"],"relation":{},"ISSN":["0953-8194","1365-2826"],"issn-type":[{"value":"0953-8194","type":"print"},{"value":"1365-2826","type":"electronic"}],"subject":[],"published":{"date-parts":[[2006,3,24]]}}}