Adrenomedullin in the rat testis. II: Its production, actions on inhibin secretion, regulation by follicle-stimulating hormone, and its interaction with endothelin 1 in the Sertoli cell.
The present study demonstrates the expression of adrenomedullin (ADM) in the rat Sertoli cells and its effect on inhibin production. The regulation of ADM by FSH and its interaction with endothelin 1 (EDN1) in the rat Sertoli cells have also been established. Primary culture of Sertoli cells secreted 414+/-27 pg immunoreactive ADM per 10(6) cells in 24 h and expressed Adm mRNA. In addition, the Sertoli cell was shown to co-express mRNAs encoding for the calcitonin receptor-like receptor (CALCRL) and receptor activity-modifying proteins (RAMPs) 1-3. These may account for the specific binding of ADM to the Sertoli cells. Administration of ADM to Sertoli cells resulted in an enhancement of basal and FSH-stimulated inhibin B production. On the other hand, the production of ADM and the mRNA levels of Calcrl and Ramp2 in the Sertoli cells were suppressed by FSH. The results suggest that ADM, via its control in the secretion of inhibin B, may play a role in regulating spermatogenesis as well as the hypothalamus-pituitary-gonad feedback system. In addition, like in the Leydig cell, ADM and EDN1 were found to regulate the production of each other in opposite directions in the Sertoli cells, suggesting the presence of yet another local regulatory mechanism in the rat testis that may be important in modulating testicular functions regulated by gonadotropins.
Chan
Yuen-Fan
YF
Department of Anatomy, the Centre of Heart, Brain, Hormone, and Healthy Aging, Faculty of Medicine, The University of Hong Kong, Hong Kong, China.
Tang
Fai
F
O
Wai-Sum
WS
D053607:Adrenomedullin / Q000096:biosynthesis / Q000235:genetics / Q000494:pharmacology / Q000502:physiology*; D000818:Animals; D058286:Calcitonin Receptor-Like Protein; D002478:Cells, Cultured; D004347:Drug Interactions; D019332:Endothelin-1 / Q000378:metabolism* / Q000494:pharmacology; D025461:Feedback, Physiological; D005640:Follicle Stimulating Hormone / Q000494:pharmacology / Q000502:physiology*; D015870:Gene Expression / Q000187:drug effects; D007265:Inhibins / Q000378:metabolism*; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics; D008297:Male; D008565:Membrane Proteins / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D058263:Receptor Activity-Modifying Protein 2; D058261:Receptor Activity-Modifying Proteins; D018003:Receptors, Calcitonin / Q000235:genetics; D012708:Sertoli Cells / Q000187:drug effects / Q000378:metabolism*; D013091:Spermatogenesis / Q000502:physiology; D013737:Testis / Q000187:drug effects / Q000378:metabolism*
D058286:Calcitonin Receptor-Like Protein; C545580:Calcrl protein, rat; D019332:Endothelin-1; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D012333:RNA, Messenger; C545509:Ramp2 protein, rat; D058263:Receptor Activity-Modifying Protein 2; D058261:Receptor Activity-Modifying Proteins; D018003:Receptors, Calcitonin; C422364:inhibin B; D053607:Adrenomedullin; D007265:Inhibins; D005640:Follicle Stimulating Hormone