Enzyme histochemical studies in testes and seminal vesicles of the Pied flycatcher (Ficedula hypoleuca) during the breeding season

Abstract

Enzymatic conditions in testes and seminal vesicles of the Pied flycatcher during the breeding season were studied by histochemical techniques. The following enzyme activities were studied: glucose‐6‐phosphatase dehydrogenase (G‐6‐PDH), NADPH2‐diaphorase, glutamic dehydrogenase (GDH), NADH2‐diaphorase, adenosine triphosphatase (ATPase) and acid phosphatase. Phospholipids and PAS‐positive substances were also studied. Towards the end of the nest‐building period, a time when the males showed maximal sexual activities, some enzyme activity changes were observed. There was an increase of the GDH activity in the sperm bundles, an increase of the ATPase activity in the interstitium and tunica propria of the tubuli seminiferi. The phospholipid content increased in all spermatogenetic cells and the PAS‐positive material increased in the Sertoli cells and spermatozoa. The enzymic activities indicated a steroid production in the Leydig cells. The epithelium of the seminal vesicles did not show any variations in enzyme activities as long as the Leydig cells persisted. Most enzymes showed a very high activity during this time, indicating a secretory function of the epithelium. The amount of phospholipids increased at the end of the nest‐building period. Parallel with the degeneration of the epithelium the enzymic activities, as well as the phospholipid content, were lowered markedly.