Expression of Apoptosis Gene Bok in the Rat Ovary / 대한산부인과학회잡지

OBJECTIVE: Bok, Bcl-2-related ovarian killer, is a proapoptotic Bcl-2 family protein identified in the ovary based on its dimerization with the antiapoptotic protein Mcl-1. The present study examined the hormonal regulation and localization of Bok messenger RNA levels in the rat ovary during the follicle development. METHODS: We used the female rats of SD strain. Bok mRNA levels in the ovary were determined by Northern blot analysis. In situ hybridization were performed to determine the specific ovarian cell type expressing Bok mRNA. RESULTS: Northern blot analysis of ovaries obtained from immature rats revealed increasing levels of Bok mRNA during postnatal development. The major cell types expressing Bok mRNA were the granulosa cells of preantral and atretic follicles. Treatment of immature rats with diethylstilbestrol (DES) for 24-48 h increased ovarian Bok mRNA levels. Bok mRNA was remained the same levels in rats removed DES for 24- 48 h to induce apoptosis. High signals of Bok mRNA after DES treatment were detected in granulosa cells of early antral follicles. Treatment of immature rats with pregnant mare's serum gonadotropin (PMSG) for 12 h increased markedly ovarian Bok mRNA expression which was detected mainly in preantral and atretic follicles. Interestingly, low levels of Bok mRNA were also expressed in granulosa cells of preovulatory follicles. Treatment of PMSG-primed rats with human chorionic gonadotropin (hCG) stimulated strongly ovarian Bok mRNA expression at 6-9 h. At that time, Bok mRNA was expressed in granulosa cells of atretic and small growing follicles. In adult estrus cyclic ovaries, Bok gene expression was higher on proestrus and estrus than metaestrus and diestrus. Moreover, the highly increased expression of Bok mRNA was found in rat ovaries at 48 h after hypophysectomy. CONCLUSION: These results demonstrate that Bok is one of proapoptotic Bcl-2 members expressed in early growing and atretic follicles during the ovarian follicular development. Gonadotropins induce a transient increase of Bok gene expression in granulosa cells of preantral and preovulatory follicles indicating some role in the ovulatory process.

Effect of Extracorporeal Shock Wave on Ovary of Sprague-Dawley Rat / 대한비뇨기과학회지

Ovaries lie near the distal ureter where extracorporeal shock wave lithotripsy (ESWL) of calculi is performed. The question whether ESWL may induce morphological changes in ovary should be investigated in animal experiments. After applying shock waves to ovary of Sprague Dawley female rat, the histopathologic changes within the tissue of ovary were observed immediately after shock waves and after recovery. For animal subjects, 25 healthy rats weighing about 250 grams each were used. Five rats were designated as control, and remaining 20 received shock waves at 20 kV for 1,000 times using Pendulum-ESWL (Lithoring), a third generation lithotriptor. The 20 rats were divided into 4 groups before shock waves, and each group was sacrificed after 1, 7, 14, and 28 days, respectively, in order to compare the observed histopathologic changes. Edema, congestion and hemorrhage were observed in ovary after 1 and 7 days of shock waves, but the edema and congestion were significantly reduced on the 14th day and completely disappeared on the 28th day. There was no ovarian follicular changes or fibrosis on the whole. It is thought that the extracorporeal shock waves have no specific effects on the tissues of ovary, but further studies ate needed to determine its long term effects.

Alteration of lipid composition, Na+, Κ+-ATPase and Δ5-3ß-hydroxy steroid dehydrogenase activities in microsomal membranes of mature toad ovary in different seasons.

Microsomal membranes isolated by sucrose density gradient centrifugation from mature toad ovary has been found to vary significantly in lipid composition and various enzyme activities in different seasons. Na+, Κ+-ATPase activity is the highest in breeding season (rainy season). Significantly the optimum temperature for enzyme activity is 30°C. The other enzyme Δ5-3ß-hydroxysteroid dehydrogenase activity is also lower in hibernation period than other seasons. The total phospholipid, sterol and fatty acid contents differ significantly between seasons. The poly-unsaturated fatty acid, except arachidonic acid content in hibernation period is much lower than that during other seasons. The sterol content is also the lowest in this season. The present findings indicate that during hibernation period the membrane is more rigid and the metabolic activity of the animal is slow because of a lower level of various functionally important enzyme activities.