title: Experimental endocrine manipulation by contraceptive regimen in the male marmoset (Callithrix jacchus).
abstract: Marmosets are used as preclinical model in reproductive research. In contrast to other primates, they display short gestation times rendering this species valid for exploration of effects on fertility. However, their peculiar endocrine regulation differs from a those of macaques and humans. We subjected male marmosets to previously clinically tested hormonal regimens that are known to effectively suppress spermatogenesis. Beside a control group, seven groups (each n=6) were investigated for different periods of up to 42 months: regimen I, (four groups) received testosterone undecanoate (TU) and norethisterone enanthate (NETE); regimen II, (two groups) received TU and NETE followed by NETE only; and regimen III, (one group) received NETE only. Testicular volume, cell ploidy and histology, endocrine changes and fertility were monitored weekly. TU and NETE and initial TU and NETE treatment followed by NETE failed to suppress spermatogenesis and fertility. Testicular volumes dropped, although spermatogenesis was only mildly affected; however, testicular cellular composition remained stable. Serum testosterone dropped when NETE was given alone but the animals remained fertile. Compared with controls, no significant changes were observed in sperm motility and fertility. Administration of TU and NETE affected testicular function only mildly, indicating that the regulatory role of chorionic gonadotrophin and testosterone on spermatogenesis is obviously limited and testicular function is maintained, although the endocrine axis is affected by the treatment. In conclusion, marmosets showed a different response to regimens of male contraception from macaques or men and have to be considered as a problematic model for preclinical trials of male hormonal contraception.
authors: Institute of Reproductive and Regenerative Biology, Centre of Reproductive Medicine and Andrology, University of Münster, Albert-Schweitzer-Campus 1, 48129 Münster, Germany. joachim.wistuba@ukmuenster.de
authors: Joachim
authors: J
authors: Wistuba
authors: C Marc
authors: CM
authors: Luetjens
authors: Jens
authors: J
authors: Ehmcke
authors: Klaus
authors: K
authors: Redmann
authors: Oliver S
authors: OS
authors: Damm
authors: Antje
authors: A
authors: Steinhoff
authors: Reinhild
authors: R
authors: Sandhowe-Klaverkamp
authors: Eberhard
authors: E
authors: Nieschlag
authors: Manuela
authors: M
authors: Simoni
authors: Stefan
authors: S
authors: Schlatt
mesh_terms: D000818:Animals; D000988:Antispermatogenic Agents / Q000008:administration & dosage*; D001835:Body Weight / Q000187:drug effects; D002144:Callithrix / Q000097:blood*; D006063:Chorionic Gonadotropin / Q000378:metabolism; D004822:Epididymis / Q000187:drug effects; D005298:Fertility / Q000187:drug effects*; D008297:Male; D023421:Models, Animal; D009640:Norethindrone / Q000008:administration & dosage / Q000031:analogs & derivatives*; D009929:Organ Size; D010902:Pituitary Gland / Q000378:metabolism; D011003:Ploidies; D013081:Sperm Motility; D013737:Testis / Q000187:drug effects / Q000378:metabolism; D013739:Testosterone / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000097:blood
chemical_list: D000988:Antispermatogenic Agents; D006063:Chorionic Gonadotropin; D013739:Testosterone; C010792:testosterone undecanoate; C024319:norethindrone enanthate; D009640:Norethindrone