| At present, alkylphenol polyethoxylates (APEs) as industrial materialare used broadly in the world. Most of the APEs and its ramifications, with the stablechemical property, are difficult to degrade, may concentrate through the food chain.Therefore it is very easy for the APEs to enter organism, disturb the normal hormoneeffects and have profound and all-pervading influence on the creatural reproduction.Bisphenol A (BPA) is one of the alkylphenol polyethoxylates. In this study, Ranachensiensis were used as experimental animals, 17β-estradiol (E2) as positivecomparison. At the different stages of spermatogenesis, R. chensiensis were exposed indifferent concentrations of BPA and E2 in order to observe the effects of environmentalestrogen BPA on spermatogenesis of R. chensiensis by histology andimmunohistochemistry. The main results and conclusions as follows:1. To understand the effects of BPA on spermiation and fecundation of R.chensinensis. At breed season, adult male R. chensinensis were exposed respectively toBPA (5×10-7M, 5×10-8M), E2 (5×10-9M, 5×10-10M), 1‰ethanol as solvent controland control, while adult females were exposured respectively to BPA (5×10-7M, 5×10-8M) 62 days. Ovulation, spermiation and hatching ratio were observed and recorded.The results indicated that BPA didn't affect ovulation. Observation of microstructure ofspermary under light microscope showed that most spermatozoa still stayed in the wallof seminiferous tubules and were surrounded by Sertoli cells treated with BPA and E2.While in solvent control and control group, most spermatozoa have left the wall of thetubules and gathered in the lumen of the seminiferous tubules. It could be concludedthat BPA can inhibit spermiation of R. chensinensis, affecting fecundation andincubation.2. To study the effects of BPA on spermatogenesis of R. chensiensis, at thedifferent stages of spermatogenesis, which including spermatozoa emissions stage,spermatogonia proliferation stage, spermatocytes actively divided stage, spermiogenesisstage, spermatozoa sperm storage overwintering stage. Adult male R. chensinensis wereexposed respectively to BPA (5×10-7M , 5×10-8M), E2 (5×10-9M, 5×l0-10M), 1‰ethanol as solvent control and control, at every stage about 60 days. The resultsindicated that, in groups treated with BPA and E2, Testis interstitial tissue thicken at the stage of spermatozoa emissions and spermatozoa sperm storage overwintering, andspermatozoa emissions were restrained at the stage of spermatozoa emissions,spermatogonia and sertoli cells Apoptosis at the stage of spermatogonia proliferation,spermatocytes and sertoli cells proliferation were restrained at the stage ofspermatocytes actively divided, spermatozoa formation and muture were delayed at thestage of spermiogenesis. It could be concluded that BPA can affect the progress ofspermatogenesis of R. chensiensis, and at the different stage of spermatogenesis, theeffects of mechanism on spermatogenesis of R. chensiensis is different.3.To examine the hormonal distribution and accepters's expression in testis of R.chensiensis during the process of spermatogenesis with the immunohistochemistry. Theresults indicated: Firstly, the positive reaction of testosterone (T) and androgen receptor(AR) in testis of R. chensiensis was lower in April, and enhanced in June, continuallystrengthened in Augest, but reduced in September, and obviously weakened inDecember; Secondly, the positive reaction of E2 and estrogen receptor (ER) in testis ofR. chensiensis was stronger in April, but reduced in June and Augest, evidentlyenhanced in September, and reduced markedly in December; Thirdly, the positivereaction of aromatase (ARO) in testis of R. chensiensis was stronger in April, reduced inJune, enhanced in Augest, reduced again in September, obviously enhanced inDecember. It is obvious that the change of T is consistent with AR, that of E2 is alsoconsistent with ER, and that of ARO is basically consistent with E2 and ER; the changelaw of E2 and T is correlative negatively. These showed this experiment with theimmunohistochemistry, which was used to check the changes of T, AR, E2,ER andARO, is reasonable in theory. The contents of T,AR,E2,ER and the expressed changelaw are nearly interrelated to the progress of spermatogenesis of R. chensiensis. Therelationship is according with the basic law of hormone regulation of the progress ofspermatogenesis of the vertebrate.4. To examine the effects of BPA on hormones and receptors in testis of R.chensiensis during the process of spermatogenesis with the immunohistochemistry.Theresults as follows:(1) Compared with control group, the positive reactions of T in testis of alldisposed groups enhanced in April, August and December, but weakened in June andSeptember. AR wenkened in April and June, enhanced in Augest, and no obbiouslychanged in September and December. (2) Compared with control group, the positive reactions of E2 in testis of alldisposed groups enhanced in April, June, August and December, but weakened inSeptember. ER wenkened in April, September and December, but enhanced slightly inJune and Augest.(3) Compared with control group, the positive reactions of ARO in testis of alldisposed groups, weakened in April, June, Augest and December, enhanced inSeptember.These results showed that BPA could obviously affect the content of hormones andthe expression level of receptors in testis of R. chensiensis during the process ofspermatogenesis, but the effects have discrepant in different stages of spermatogenesis,also different in different concentrations of BPA.It is suggested that BPA can interfereincretion function in the process of procreation through the living water of R.chensiensis, but the different spermatogenesis stages of R. chensiensis and the differentindividuals for the sensitivity degree of BPA are different, which leads to anunconspicuous law of the effects of BPA on incretion function in the process ofprocreation.
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