Ischemic postconditioning lightening ischemia/reperfusion apoptosis of rats via mitochondria pathway.

OBJECTIVE:   To explore whether ischemic postconditioning will lighten hepatic apoptosis caused by hepatic ischemia/reperfusion injury by inhibiting the mitochondria pathway. MATERIALS AND METHODS: Pathomorphology of hepatic tissues in rats was observed under an optical microscope after hematoxylin-eosin (HE) staining. Hepatic apoptosis was detected using agarose gel electrophoresis (AGE) with DNA fragments and flow cytometry. Changes in morphology structure of mitochondria in hepatocytes of rats were observed under an electron microscope. Changes in mitochondria transmembrane potential of hepatocytes of rats were detected using a laser scanning confocal microscope (LSCM). Western blotting was adopted to detect changes in the expression of caspase-3 and cytochrome C protein in hepatocytes of rats. RESULTS: Compared with that in I/R group, swelling degree of mitochondria in most hepatocytes of rats in ischemic postconditioning (IPOST) group and IPC group was lighter. Changes in expression of caspase-3 and cytochrome C protein in hepatic cells of rats: caspase-3 was lowly expressed and cytochrome C was highly expressed in S group. The expression of caspase-3 was evidently higher in I/R group than that in S group and expression of cytochrome C protein was evidently lower than that in S group (p<0.05). The expression of caspase-3 protein was evidently decreased in IPOST group and IPC group and the expression of cytochrome C protein was evidently increased (p<0.05). CONCLUSIONS: IPOST can reduce hepatic apoptosis caused by hepatic ischemia/reperfusion injury in rats, which may be achieved by inhibiting the mitochondria pathway.

[Inhibition of ova fertilizability by pseudolaric acid B in hamster].

Pseudolaric acid B (PA), a diterpenoid compound isolated from the root of Pseudolarix kaempferi Gorden, was injected into hamster ovarian bursa with various concentration before ovulation. The successful rate of fertilization of ova was significantly decreased, but no effect was observed on spermatozoa activity and fertilizing ability. Hamster ova with or without cumulus were treated with PA at a concentration higher than 50 micrograms/ml in the medium, the fertilizing rate of ova was reduced markedly. At the concentration of 5 micrograms/ml, only the capacity of fertilization of the cumulus-free ova was inhibited. When PA was injected ig 20 mg/kg daily to hamsters (female) for 4 d before mating, partial antifertility effect was observed.