Barnea E R, Shurtz-Swirski R
University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School, Camden.
Hum Reprod. 1992 Mar;7(3):305-10. doi: 10.1093/oxfordjournals.humrep.a137640.
The polycyclic aromatic hydrocarbons are major environmental pollutants. Benzo[a]pyrene and 3-methylcholanthrene are prominent members of this group of compounds. In the present study, we have examined the effect of these carcinogens/mutagens upon human chorionic gonadotrophin (HCG) secretion in the first trimester placenta in vitro. At 7-9 weeks in static cultures, exposure to 50 microM benzo[a]pyrene for 24 h increased beta-HCG secretion by placental explants. The effect after 6 h of incubation was less apparent. The effect of 5 microM benzo[a]pyrene at the two time points also was less significant than 50 microM benzo[a]pyrene. In explants exposed to 50 microM 3-methylcholanthrene, the effect on HCG secretion was also stimulatory. In superfusion of placental explants pretreated overnight with benzo[a]pyrene, there was a similar increase in the pattern of pulsatile beta-HCG secretion, as analysed by the area under the curve and the pulse amplitude, which was most evident at 24 h with the 50 microM dose. No significant effect on pulse frequency was noted. The effect of 50 microM 3-methylcholanthrene was also stimulatory. In order to determine the functional integrity of the explants treated with benzo[a]pyrene, the effect of 1 min pulses of 10(-10) gonadotrophin-releasing hormone (GnRH) analogue (a known HCG stimulator in superfusion) was tested, demonstrating that it increased beta-HCG secretion compared to controls. In addition, there was also an increase in whole HCG, as measured by the Tandem-R assay following exposure to benzo[a]pyrene. In conclusion, short-term exposure to carcinogens increases HCG secretion of placental explants in early pregnancy and this effect is maintained after removal of the xenobiotic.
多环芳烃是主要的环境污染物。苯并[a]芘和3-甲基胆蒽是这类化合物中的重要成员。在本研究中，我们检测了这些致癌物/诱变剂对孕早期胎盘体外分泌人绒毛膜促性腺激素（HCG）的影响。在7 - 9周的静态培养中，胎盘外植体暴露于50微摩尔的苯并[a]芘24小时后，β-HCG分泌增加。孵育6小时后的效果不太明显。在这两个时间点，5微摩尔苯并[a]芘的作用也比50微摩尔苯并[a]芘的作用小。在暴露于50微摩尔3-甲基胆蒽的外植体中，对HCG分泌的影响也是刺激性的。在用苯并[a]芘预处理过夜的胎盘外植体的灌注实验中，通过曲线下面积和脉冲幅度分析，搏动性β-HCG分泌模式有类似的增加，在24小时时50微摩尔剂量最为明显。未观察到对脉冲频率有显著影响。50微摩尔3-甲基胆蒽的作用也是刺激性的。为了确定用苯并[a]芘处理的外植体的功能完整性，测试了10^(-10)促性腺激素释放激素（GnRH）类似物（灌注中已知的HCG刺激剂）1分钟脉冲的作用，结果表明与对照组相比，它增加了β-HCG分泌。此外，通过串联R法测量，暴露于苯并[a]芘后总HCG也有所增加。总之，短期暴露于致癌物会增加孕早期胎盘外植体的HCG分泌，并且在去除外源性物质后这种作用仍然存在。
