ABSTRACT
Effect of cumulative doses (7, 14 and 28 mgkg-1 body weight) of testosterone (T) and estradiol-17b (E2) on total phospholipids (TP), phosphatidylcholine (PC), phosphatidylserine (PS), phosphatidylinositol (PI) and phosphatidylethanolamine (PE) in tissues were investigated during the gonadal recrudescence, in prespawning phase of the annual reproductive cycle in intact and ovariectomized freshwater catfish, Heteropneustes fossilis. After ovariectomy, the hepatic levels of TP and PE were elevated and remained unaffected for PC, PS and PE when compared with control. In general, T and E2 were stimulatory for a specific class of phospholipid in tissues of intact and ovariectomized catfish. These effects were higher at 14 and 28 mg kg-1 body weight in ovariectomized catfish whereas 7 mgkg-1 body weight of T and E2 have pronounced effect in intact ovaries. In conclusion, the various phospholipid biosynthesis were under T and E2 dependent. Among the phospholipid, the PC was the main constituent and was sex steroid dependent biosynthesis during prespawning phase.
ABSTRACT
Effect of cumulative doses of estradiol -17beta (E2-7, 14 and 28 mg/kg body weight) and 17alpha, 20beta-dihydroxy-4-pregnen-3-one (17alpha,20betaP-7, 14 and 28 mg/kg body weight) on total phospholipids (TP) and various phospholipids- phosphatidylcholine (PC), phosphatidylserine (PS), phosphatidylinositol (PI) and phosphatidylethanolamine (PE) on liver plasma and ovary were investigated during the reproductively active preparatory and prespawning phases of the annual reproductive cycle in the freshwater female catfish, H. fossilis. The effect of E2 on TP was generally stimulatory and has pronounced effect than 17alpha,20betaP during both the phases. The levels of PC was promoted high during prespawning phase by E2 comparatively very less than by 17alpha, 20betaP in studied tissues during both the phases. The levels of PS after E2 treatments was maximum in all tissues during prespawning phase whereas 17alpha,20betaP was effective only in liver during this phase. The PI was elevated in liver during preparatory phase but its elevation was in all studied tissues during prespawning phase after E2 treatments. The levels of PI was most effective in ovary during preparatory phase in response to 17alpha,20betaP. The levels of PE was declined in liver but elevated in ovary after E2 treatments during both the phases. Treatments of E2 during preparatory phase showed greater number of vitellogenic oocytes as compared to 17alpha,20betaP treatments. The present finding has demonstrated that estradiol-17beta has more pronounced effects than the 17alpha,20beta P in regulation of different phospholipids and ovarian recrudescence during reproductively active phases and among the phospholipids the PC is the main phospholipids of vitellogenin/ovarian lipids in H. fossilis.