Analysis of Spermatogenic Failure in DAZL-Deficient Rats.

Abstract

<p>(A) Relative numbers of spermatogenic cell types/1000 Sertoli cells in testes of 4 month old wildtype and transgenic <i>DAZL</i>-deficient rats (+/−SEM, n = 3 rats/group). Undifferentiated type A spermatogonia (Undif), differentiating type A spermatogonia (Type A), intermediate to type B spermatogonia (Int-Type B), preleptotene spermatocytes (PL), leptotene-zygotene spermatocytes (lept-zygo), pachytene-diplotene spermatocytes (Pachy-Di), secondary spermatocytes-round spermatids (SS-RS), elongating spermatids (ES). Significant differences (i.e. p<0.05) in testis cell types scored in wildtype and DAZL-deficient rats were determined for SS-RS (p = 0.022) and ES (p<0.0001) using unpaired two-tailed students t-test. (B) Histological cross-sections of seminiferous tubules from 4 month old wildtype (<i>Top left</i>) and transgenic <i>DAZL</i>-deficient rats (<i>Top right</i>). <i>Bottom left and right</i> show higher magnification images of boxed regions in the <i>Top</i> panels. Scale bars = 100 µm. (C) Images of spermatogonial types in testis sections from wildtype rats at stages VIII, XI, XIII, XIV, II and V of spermatogenesis. Types of undifferentiated (Undif) and differentiating spermatogonia (A1, A2, A3, A4, Int, B) were determined by analysis of staining patterns in nuclei at specific stages of spermatogenesis. Scale bar = 30 µm. (D) Images of spermatogonial types in testis sections from <i>DAZL</i>-deficient rats. Because stages of the epithelial cycle could not be classified in these rats, types of undifferentiated (Undif) and differentiating spermatogonia (A1-like, A2-like, A3-like, A4-like, Int-like, B-like) were estimated based on staining profiles of spermatogonia in wildtype rats. Scale bar = 30 µm.</p