Abstract：OBJECTIVE: It is still unexplained whether hypoxia of renal tissues induced by asphyxia is closely related to acute renal tubular epithelial cells (RTEs) injury. This paper aims to study the effect of hypoxia on G 1/S transition in neonatal pig's RTEs in vitro so as to explore the relationship between hypoxia and acute RTEs injury. METHODS: A hypoxic cell model of G 1/S transition of RTEs in neonatal piglets was established by sodium cyanide exposure. Some of the hypoxic G 1/S cells received cantharidin and were used as the Intervention group. The non-hypoxic and non-interfered G 1/S cells were used as the Control group. Cell distribution rate and cell apoptosis rate of G 1 and S phases were determined by flow cytometry 0, 60, 120 and 180 minutes after cessation of hypoxia. The cell p21 expression was measured by immunocytochemistry. RESULTS: The cell cycle distribution rate of the S phase in the Hypoxic group 0 and 60 minutes after cessation of hypoxia ( 1.4%± 2.5% and 0.5%± 0.9%) were lower than those of the Intervention group ( 98.3%± 1.6% and 99.0%± 1.0%) (P< 0.01). The cell apoptosis rates in the Hypoxic group 120 and 180 minutes after cessation of hypoxia ( 33.6%± 0.8% and 37.5%± 1.2%) were higher than those of the Intervention group ( 20.9%± 1.7% and 22.5%± 1.1%) and the Control group ( 25.6%± 1.1% and 23.6%± 1.4%) (P< 0.01). The cell distribution rate of the G 1 phase had a positive liner correlation with cell p21 expression of the same term (r= 0.64, P< 0.01), but it was not related to the cell apoptosis rate. CONCLUSIONS: Acute RTEs injury in the perinatal period is closely related to hypoxia. The possible mechanism is that hypoxia may restrain the advance of G 1/S transition and increase cell apoptosis rate of the S phase.
SHEN Qing,YAO Yu-Jia,XIONG Ying et al. Effect of hypoxia on cell cycle of G1/S renal tubular epithelial cells of the newborn pig[J]. CJCP, 2004, 6(4): 265-268.
