Fig 1.
Testes and epididymis of Myotis nigricans in the four periods of the annual reproductive cycle.
Histological sections stained with hematoxylin-eosin. (A-D) Testes: (A) Active period. Note the continuous spermatogenesis, with the presence of all germinative cell types; (B) Regressing period. Note the initiation of the process of regression, with the absence of type B spermatogonia and spermatocytes; (C) Regressed period. Note the presence of only Sertoli cells and spermatogonia, with no spermatogenesis and two tubules that present spermatozoa inside them (asterisks); (D) Recrudescence period. Note the reactivation of spermatogenesis). (E-P) Epididymal regions (caput: E-H; corpus: I-L; cauda: M-P). Note the large lumen and the large secretory cells in the three prostatic regions during the Active and Regressing periods (E-F, I-J and M-N); the decrease in the luminal proportion, the increase in the amount of epithelial and interstitial tissues and the approximation/compression of the secretory cells in the three regions (caput: G; corpus: K; cauda: O) in the Regressed period; and the reactivation of the epithelium in the three epididymal regions from the Regressed to the Recrudescence periods (caput: G-H; corpus: K-L; cauda: O-P). (ES, elongated spermatids; I, spermatocytes; RS, round spermatids; Se, Sertoli cells; Sg, spermatogonia). Scale bars = 20μm.
Fig 2.
Weights variations during the four periods of the annual reproductive cycle of Myotis nigricans.
(A) Variations in mean body weight. (B) Variations in mean gonad weight. (C) Variations in the epididymal weight. Different letters indicate statistically significant differences (ANOVA at p < 0.05).
Fig 3.
Variation in the epididymal tissues of Myotis nigricans during the annual reproductive cycle.
(A-C) Graphs showing the variation in the amount of epithelium, lumen and interstitial tissue in the caput (A), corpus (B) and cauda epididymis (C). (D-F) Graphs showing the variation in the tubular and luminal diameters and epithelium height in the caput (D), corpus (E) and cauda epididymis (F). Data in the graphs are given as the mean ± s.d. Different letters indicate statistically significant differences (ANOVA at p < 0.05).
Fig 4.
Variation in PCNA (A-J) and AR (K-T) expression in the three epididymal regions of Myotis nigricans.
(A) Graphic showing the variation of PCNA expression in the three epididymal regions during the four periods of the annual reproductive cycle. (B-C) Photomicrographs showing the general pattern of the caput epididymis in Active (B) and Recrudescence periods (C). (D-E) Photomicrographs showing the general pattern of the corpus epididymis in Active (D) and Recrudescence periods (E). (F-G) Photomicrographs showing the general pattern of the cauda epididymis in Recrudescence (F) and Regressed periods (G). (H-J) Negative controls of the PCNA immunoreaction of the caput (H), corpus (I) and cauda epididymis (J). (K) Graphic showing the variation of AR expression in the three epididymal regions during the four periods of the annual reproductive cycle. (L-M) Photomicrographs showing the general pattern of the caput epididymis in Active (L) and Recrudescence periods (M). (N-O) Photomicrographs showing the general pattern of the corpus epididymis in Active (N) and Recrudescence periods (O). (P-Q) Photomicrographs showing the general pattern of the cauda epididymis in Recrudescence (P) and Regressed periods (Q). (R-T) Negative controls of the AR immunoreaction of the caput (R), corpus (S) and cauda epididymis (T). Data in the graphs are given as the mean ± s.d. Different letters indicate statistically significant differences (ANOVA at p < 0.05). Scale bars = 10 μm.
Fig 5.
Variation of ERα (A-J) and aromatase (K-Z) expressions in the three epididymal regions of Myotis nigricans.
(A) Graphic showing the variation of ERα expression in the three epididymal regions during the four periods of the annual reproductive cycle. (B-C) Photomicrographs showing the general pattern of the caput epididymis in the Active (B) and Recrudescence periods (C). (D-E) Photomicrographs showing the general pattern of the corpus epididymis in the Active (D) and Recrudescence periods (E). (F-G) Photomicrographs showing the general pattern of the cauda epididymis in the Active (F) and Regressed periods (G). (H-J) Negative controls of the ERα immunoreaction of the caput (H), corpus (I) and cauda epididymis (J). (K-N) Photomicrographs showing the general pattern of aromatase expression in the caput epididymis in Active (K), Regressing (L), Regressed (M) and Recrudescence periods (N). (O) Negative control of the aromatase immunoreaction of the caput epididymis. (P-S) Photomicrographs showing the general pattern of aromatase expression in the corpus epididymis in Active (P), Regressing (Q), Regressed (R) and Recrudescence periods (S). (T) Negative control of the aromatase immunoreaction of the corpus epididymis. (U-Y) Photomicrographs showing the general pattern of aromatase expression in the cauda epididymis in Active (U), Regressing (W), Regressed (X) and Recrudescence periods (Y). (Z) Negative control of the aromatase immunoreaction of the cauda epididymis. Data in the graph are given as the mean ± s.d. Different letters indicate statistically significant differences (ANOVA at p < 0.05). Scale bars = 10 μm.