OBJECTIVETo study the effect of high power microwave (HPM) radiation on the testicular germ cell apoptosis.

METHODSOne hundred and twenty-five Spraque-Dawley rats were randomly divided into two groups, unexposed control group and experimental group(further divided into four subgroups: 10 mW/cm2 5 min, 10 mW/cm2 10 min, 20 mw/cm2 5 min, and 20 mW/cm2 10 min), and then the experimental group was radiated with S wave band of 10 mW/cm2, 20 mW/cm2 high power microwave for 5 or 10 min. Testicular samples were taken at 6 h, 24 h, 48 h, 72 h and 5 d after radiation and separately studied. At the end of the process, testicular germ cell apoptosis was detected by in situ terminal deoxynucleotityl transferase mediated dUTP nick end labeling (TUNEL).

RESULTSThe number of apoptotic cells of the 6 h, 24 h and 48 h experimental groups at 5 min after 10 and 20 mW/cm2 radiation was remarkably larger than that of the controls (P < 0.01), especially after 10 mW/cm2 radiation, the number of the 6 h group reached the peak (161.27 +/- 5.90) /5 convoluted seminiferous tubules. The changes in the other experimental groups had no significant difference compared with the controls (P > 0.05).

CONCLUSIONHPM can increase germ cell apoptosis of the rat testis, which is related to the time of radiation and sample acquisition. In the condition of the present test, 5 minutes of HPM radiation may significantly enhance testicular germ cell apoptosis and damage, which in turn may influence the reproductive function of the rats.