title: Ontogeny of leptin and its receptor expression in mouse testis during the postnatal period.
abstract: The mechanism by which leptin regulate male reproductive development during postnatal periods remain to be determined. Using immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR), we established that leptin is expressed in mouse testis with a cell-type and stage-dependent manner during the postnatal period. In testes of 5-day-old mice, leptin expression was mainly restricted to gonocytes, whereas the immunostaining of leptin was confined to spermatogonia in 10-day-old testes. From Day 20 and onwards, stage-specific expression of leptin was evident in spermatocytes at stages VII-XII of the cycle in the seminiferous epithelium. RT-PCR showed that leptin and its receptor isoforms, Ob-Ra, Ob-Rb, and Ob-Re were all expressed in testes from 5- to 60-day-old mice. The mRNA for Ob-Ra and Ob-Re, but not Ob-Rb or leptin were identified in both immature (14-day-old) and adult (60-day-old) isolated Leydig cells. These results suggest that besides its primary actions at the hypothalamic-pituitary level, leptin has direct effects in the proliferation, differentiation of germ cells and the modulation of testicular steroidogenesis, using both autocrine and paracrine mechanisms.
authors.affiliation: Animal Physiology, University of New England, Armidale, New South Wales, Australia. Muren.Herrid@csiro.au
authors.forename: Muren
authors.initials: M
authors.lastname: Herrid
authors.forename: Tim
authors.initials: T
authors.lastname: O'Shea
authors.forename: James R
authors.initials: JR
authors.lastname: McFarlane
mesh_terms: D000818:Animals; D019898:Autocrine Communication / Q000502:physiology; D002454:Cell Differentiation / Q000502:physiology; D049109:Cell Proliferation; D005786:Gene Expression Regulation / Q000502:physiology*; D007030:Hypothalamo-Hypophyseal System / Q000166:cytology / Q000254:growth & development / Q000378:metabolism; D007150:Immunohistochemistry; D020738:Leptin / Q000096:biosynthesis*; D007985:Leydig Cells / Q000166:cytology / Q000378:metabolism; D008297:Male; D051379:Mice; D019899:Paracrine Communication / Q000502:physiology; D020033:Protein Isoforms / Q000096:biosynthesis; D054411:Receptors, Leptin / Q000096:biosynthesis*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012670:Seminiferous Epithelium / Q000166:cytology / Q000254:growth & development / Q000378:metabolism*; D013090:Spermatocytes / Q000166:cytology / Q000254:growth & development / Q000378:metabolism*; D013093:Spermatogonia / Q000166:cytology / Q000254:growth & development / Q000378:metabolism*
chemical_list: D020738:Leptin; D020033:Protein Isoforms; D054411:Receptors, Leptin; C515447:leptin receptor, mouse