【摘要】 本研究分二批进行,第一批用成年雄性大鼠每天接受X射线全身照射50mGy/次和100mGy/次,剂量率为15mGy/分,6次/周,共照5周（30次）,累积剂量分别为1.5Gy和3.0Gy。受照大鼠睾丸重量在停照后4周内呈持续性减轻,以照射剂量大,停照时间长者,减轻最明显（相当于对照43.9%）。睾丸中cAMP含量于停照后1周升高,以100mGy组明显（P<0.01）,停照后2周仍显著高于对照（P<0.05）,停照后4周回降到正常较低水平。而血浆和肾上腺中cAMP和胸上腺中cGMP含量无明显变化。第二批实验动物条件与第一批相同,每天接受16.3mGy,⁶⁰Coγ射线全身照射,剂量率为45.3pGy/分,6次/周,每次照射6小时,在照射6、10、14、18、22周,累积剂量分别为0.59、0.98、1.37、1.76、2.15Gy时与相应对照组比较,垂体、睾丸中cAMP含量及睾丸重量无显著差别,证实慢性小剂量全身照射对睾丸组织的损伤主要取决于剂量率大小,剂量率愈大损伤愈明显。更多还原

【Abstract】 The effects of low-level radiation on cAMP in peasma, adrenal and testis and cGMP in adrenal of rats were studied. Adult male rats were given whole-body irradiation with x-rays at a dose rate of 15 mGy/min. They were irradiated with 50 and 100 mGy daffy for 30 days within 5 weeks with cumulative doses of 1.5 and 3.0 Gy respectively. One, two and four weeks after termination of irradiation, the levels of cAMP in plasma, the adrenal gland and testis, the level of cGMP in the adrenal gland and the weights of the body, testes and pitutary were examined. The weights of testes decreased within 4 weeks after irradiation as compared with the control and the level of cAMP in the testis was significantly increased at weeks 1 and 2 in the 3.0 Gy group. At week 4, it returned to near normal. In another experiment, animals were irradiated with ⁶⁰Co γ-ray at a dose rate of 45.3μGy/min, 16.3 mGy/6h/day and 6 days per week. At 6, 10, 14, 18 and 22 weeks, with cumalative doses of 0.59, 0.98, 1.37, 1.76 and 2.15 Gy respectively, the levels of cAMP in the pitutary and testis and testicular weight were quantified. No significant changes were found. These results suggest that dose rate is an important factor In the determination of the degree of damage of the testis following low-level irradiation.更多还原