Androgen receptor (AR), estrogen receptor-alpha (ER-alpha) and estrogen receptor-beta (ER-beta) expression in the testis of the newt, Triturus marmoratus marmoratus during the annual cycle

Expression of androgen receptor (AR), estrogen receptor alpha (ER-alpha) an d estrogen receptor beta (ER-beta) in the testis of the marbled newt (Tritu rus marmoratus marmoratus) was investigated, with special attention to chan ges during the annual testicular cycle, using light microscopy immunohistoc hemistry and Western blot analysis. Primordial germ cells, primary and seco ndary spermatogonia and spermatocytes showed a positive reaction to the 3 r eceptor antibodies during the annual reproductive cycle. Follicular cells w ere positive to AR, ER-alpha and ER-beta during the spermiogenesis and quie scence periods in the glandular tissue. Interstitial cells showed reactivit y to AR, ER-alpha and ER-beta in the spermiogenesis and the quiescence peri ods, and presented no labelling to these receptors in the proliferative per iod. These findings suggest that, as in mammals, there is an androgen-estro gen regulation of the function and development of the newt testis.