title: Hypoxia-reoxygenation-induced apoptosis in cultured neonatal rat cardiomyocyets and the protective effect of prostaglandin E.
abstract: The aim of the present study was to investigate the effect of prostaglandin (PG) E1 on hypoxia/re-oxygenation (H/R) apoptosis and the expression of bcl-2 and bax in cultured neonatal rat cardiomyocytes. The H/R model was made using the first generation of cultured neonatal rat cardiomyocytes. Hypoxia/re-oxygenation apoptosis was studied by electron microscopy and agarose gel electrophoresis. The percentage of apoptotic cells was measured by terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick end-labeling (TUNEL). The expression of bcl-2 and bax was detected by in situ hybridization and immunohistochemical staining. Most cells of the H/R group tested by electron microscopy showed cytoplasmic concentration, nuclear chromatin condensation and margination. Prostaglandin E1 (5, 15 and 45 microg/L) relieved the injury. The results of DNA electrophoresis in the H/R group showed a typical DNA ladder and the DNA ladder decreased gradually corresponding with increasing doses of PGE1. The TUNEL staining showed that the total number of apoptotic cells in the H/R group was much more than that in the PGE1 (45 microg/L) group. The results of in situ hybridization and immunohistochemical staining showed that the bcl-2 content in the H/R group was lower than that in the control group; bax content showed the reverse. Compared with the H/R group, bcl-2 content was significantly higher in the PGE1 (5, 15 and 45 microg/L) groups. However, bax content in the PGE1 (5, 15 and 45 microg/L) groups was significantly lower than that in the H/R group. 6. In conclusion, H/R injury can induce cardiomyocyte apoptosis. Prostaglandin E1 obviously has anti-apoptotic effects on cardiomyocytes and the mechanisms probably involve the inhibition of bax expression and increased expression of bcl-2.
authors.affiliation: Department of Pharmacology, College of Basic Sciences, Zhengzhou University, Zhengzhou, China.
authors.forename: Xiang-Qin
authors.initials: XQ
authors.lastname: Ma
authors.forename: Run-Fang
authors.initials: RF
authors.lastname: Fu
authors.forename: Guo-Qing
authors.initials: GQ
authors.lastname: Feng
authors.forename: Zhen-Ji
authors.initials: ZJ
authors.lastname: Wang
authors.forename: Shou-Guo
authors.initials: SG
authors.lastname: Ma
authors.forename: Shi-Ai
authors.initials: SA
authors.lastname: Weng
mesh_terms: D000527:Alprostadil / Q000494:pharmacology*; D000818:Animals; D000831:Animals, Newborn; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D002478:Cells, Cultured; D004247:DNA / Q000096:biosynthesis / Q000235:genetics; D004591:Electrophoresis, Polyacrylamide Gel; D019254:Genes, bcl-2 / Q000235:genetics; D000860:Hypoxia / Q000188:drug therapy / Q000473:pathology*; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D020287:In Situ Nick-End Labeling; D008854:Microscopy, Electron; D032383:Myocytes, Cardiac / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D010100:Oxygen / Q000502:physiology*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D051381:Rats; D051028:bcl-2-Associated X Protein / Q000096:biosynthesis / Q000235:genetics
chemical_list: D012333:RNA, Messenger; D051028:bcl-2-Associated X Protein; D004247:DNA; D000527:Alprostadil; D010100:Oxygen