Bu çal›flmada, inci kefalinde yumurta b›rakt›ktan sonra foliküllerin yap›s› ve yumurta b›rakmadan önce ve yumurta b›rakt›ktan sonra ovaryum 11-dehydrocorticosteroit (11-DHC), östradiol-17β (E2), 17α-hydroxyprogesteron (17α-OH-P) ve progesteron (P) seviyeleri araflt›r›ld›. Ovulasyondan sonra foliküllerin bol damarl› bir teka tabakas› ve bol miktarda düz endoplazmik retikulum, tubüler kristal› çok say›da mitokondri ve lipit damlalar› içeren büyük granüloza hücreleri ile karakterize edildi¤i gösterilmifltir. Ovaryum 11-DHC seviyesi yumurta b›rakmadan önce ve sonra düflüktür (38,3 ± 4,9-22,3 ± 2,6 ng/ml). E2 seviyesi yumurta b›rakmadan önce 216,8 ± 31,1 ng/ml olarak belirlendi. Bu hormon yumurta b›rakt›ktan sonra 1. ve 5. günde azald› ve 10. günde tekrar 216,8 ± 6,7 ng/ml’ye yükseldi. Bununla birlikte, E2 seviyesi 15. günde belirgin olarak düfltü (61,5 ± 17,8 ng/ml) (P < 0,01). 17α-OH-P seviyesi yumurta b›rakmadan önce düflüktü (84,5 ± 49,4 ng/ml) ve yumurta b›rakt›ktan sonra artarak 10. günde en yüksek seviyeye ulaflt› (295,7 ± 52,5 ng/ml) fakat 15. günde hafif bir düflüfl gözlendi (190 ± 21,5 ng/ml) (P > 0,01). P seviyesi yumurta b›rakmadan önce düflüktü (23,4 ± 18,3 ng/ml). Onun seviyesi yumurta b›rakt›ktan sonra artmaya bafllad› ve 10. günde maksimum seviyeye ulaflt› (200,7 ± 29,1 ng/ml) (P < 0,01) fakat 15. günde belirgin olarak düfltü (63,2 ± 19,5 ng/ml) (P < 0,01). Bu çal›flmadan elde edilen sonuçlar: a) Ovulasyondan sonraki foliküllerde granuloza hücrelerinin steroit sentezledi¤ini, b) 11-DHC’nin yumurta b›rakmadan önce ve sonra etkili olmad›¤›n›, c) E2’nin yumurta b›rakmay› uyard›¤›n›, d) 17α-OH-P ve P’un yumurta b›rakt›ktan sonra etkili oldu¤unu gösterir. ‹nci kefalinde, ovulasyondan sonraki foliküllerde apoptotik hücrelerin, E2 and P’nin yumurta b›rakt›ktan sonra en düflük seviyede oldu¤u, 15. günde artt›¤› sonucu ç›kar›labilir.

The structure of postovulatory follicles and the levels of ovarian 11-dehydrocorticosterone (11-DHC), estradiol-17b (E2), 17a-hydroxyprogesterone (17a -OH-P), and progesterone (P), before and after spawning, were studied in Chalcalburnus tarichi. It was observed that postovulatory follicles are characterized by a highly vascular thecal layer and hypertrophied granulosa cells containing dense smooth endoplasmic reticulum, many large mitochondria with tubular cristae, and lipid droplets. Ovary 11-DHC level was low in the pre- and post-spawning periods (38.3 ± 4.9-22.3 ± 2.6 ng/ml). The level of E2 was 216.8 ± 31.1 ng/ml before spawning. This hormone declined on the 1st and 5th day after spawning and increased again to the level of 216.8 ± 6.7 ng/ml on the 10th day; however, the E2 level decreased significantly on the 15th day (61.5 ± 17.8 ng/ml) (P < 0.01). The 17a -OH-P level was low (84.5 ± 49.4 ng/ml) before spawning and reached a peak (295.7 ± 52.5 ng/ml) on the 10th postspawning day, but a slight decline was observed on the 15th day (190 ± 21.5 ng/ml) (P > 0.01). The P level was low (23.4 ± 18.3 ng/ml) before spawning. Its level began to increase after spawning and reached a peak on the 10th postspawning day (200.7 ± 29.1 ng/ml) (P < 0.01), but declined significantly on the 15th day (63.2 ± 19.5 ng/ml) (P < 0.01). The results obtained from this study indicate that: a) In the postovulatory follicles, the granulosa cells produce steroids; b) 11-DHC has no effect before or after spawning; c) E2 induces spawning; d) 17a -OH-P and P have an effect after spawning. It can be concluded that the apoptotic cells in postovulatory follicles increased on the 15th day, at which time E2 and P hormones were at their lowest levels after spawning in C. tarichi.