微波辐射对大鼠睾丸P450scc mRNA表达水平的影响

Change of P450scc expression in testis of rats after microwave irradiation

目的探讨微波辐射对成年大鼠睾丸组织中细胞色素P450胆固醇侧链裂解酶(P450scc)表达水平的影响。方法采用放射免疫方法(RIA)分别测定经微波辐射后3,6,24,72h及对照组大鼠的血清睾酮含量,同时运用RTPCR方法测定睾丸组织中P450sccmRNA的表达水平变化。结果辐射组大鼠在微波辐射后3h,其血清睾酮含量及P450sccmRNA水平均显著低于对照组(分别较对照组降低83.1%和53.6%,且均P<0.01),6h后略有回升,但仍明显低于对照组(分别较对照组降低52.6%和29.2%,且均P<0.01),于24h后恢复至正常水平,在72h时再次出现显著降低(分别较对照组降低57.6%和53.5%,且均P<0.01)。结论微波辐射能在转录水平影响睾丸间质细胞P450sccmRNA的表达,从而降低睾酮的含量。

Objective To observe the change of cytochrome P450 cholesterol side chain catenase (P450scc) expression in testis tissue of adult rats after microwave irradiation. Methods Sixty rats were irradiated by microwave once for 15 minutes. At the time points of 3, 6, 24 and 72 hours after the irradiation the serum contents of testosterone in the rats were tested by using radioimmunoassay (RIA), the level of the P450scc mRNA in testis tissue was also measured by using semi-quantitative RT-PCR. Another 15 rats were used as control group. Results The contents of testosterone, the expression level of P450scc mRNA at 3 hours after microwave irradiation were significantly lower than those in the rats of the control group (decreased 83.1%, 53.6%, respectively, P<0.01). At 6 hours after microwave irradiation, although the expression of P450scc mRNA was slightly elevated it was still significantly lower than that of the control group (decreased 52.6% and 29.2%, respectively, P<0.01) and recovered in 24 hours. At 72 hours, the content of testosterone, the expression level of P450scc mRNA were significantly lowered when compared with those of the control group (decreased 57.6%, 53.5%, respectively, P<0.01). Conclusion Microwave irradiation may affect the transcription of P450scc in the Leydig cells of adult rat,thereby inhibit the testosterone synthesis and secretion.