Cholesterol In Ovary Research Articles

Impairment of steroidogenesis and reproduction in sexually mature Cyprinus carpio by phenol sulfide under laboratory conditions

Profiles of nonesterified and esterified cholesterol in ovary, liver and serum were studied in sexually mature Cyprinus carpio exposed to sublethal concentrations of phenol and sulfide for 45 days. Phenol caused a gradual and significant increase in nonesterified cholesterol in ovary and liver with a concomitant rise in the hepatosomatic index (HSI), while the gonadosomatic index (GSI) decreased gradually. Phenol exposure had little effect on serum nonesterified cholesterol. Sulfide exposure, on the other hand, resulted in a gradual and significant decrease in only ovarian nonesterified cholesterol and an increase in both hepatic and serum nonesterified cholesterol. Using [4- 14C]cholesterol as a tracer, it was found that for 45-day exposure, sulfide had an adverse effect on the transport of cholesterol from circulation to ovary. Both the pollutants had an inhibitory effect on the conversion of radiolabelled cholesterol to steroidal products.

In Vitro biosynthesis of steroids from cholesterol by the ovaries and pyloric caeca of the starfish Asterias rubens

1. 1. In vitro biosynthesis of steroids from cholesterol in ovaries and pyloric caeca of Asterias rubens has been investigated. 2. 2. The formation of pregnenolone and progesterone was demonstrated in both tissues by using 1,2- 3H-cholesterol as a precursor. 3. 3. Pregnenolone and progesterone are produced in small quantities; the ovaries appear to be more active in the biosynthesis of these steroids than the pyloric caeca. 4. 4. The results indicate the presence of the following biosynthetic enzyme systems in ovaries and pyloric caeca of Asterias rubens: a side-chain-cleaving enzyme complex and a Δ 5–Δ 4- isomerase-3β- HSD complex. 5. 5. The importance of these enzymes and the function of cholesterol for the biosynthesis of steroids will be discussed.