FIG. 4.

Effects of LH stimulation on DNA damage in Leydig cells. A) Leydig cells were isolated from and 24 mo-old Brown Norway rats stimulated with 100 ng/ml LH for 2 h and analyzed by Comet assay. Open arrow indicates a representative cell with very little or no damage. Dashed arrow indicates a cell with damaged DNA. Original magnification ×10. B) MA-10 cells were stimulated with 100 ng/ml LH for increasing times and analyzed by Comet assay. *Significantly different from control value, P < 0.05. C) Effects of vitamin E (VE) treatment on LH-induced DNA damage in MA-10 cells. MA-10 cells were stimulated with 100 ng/ml LH in the presence of 20 μM VE and analyzed by Comet assay. DNA damage was assessed by single-cell electrophoresis, with single cells determined to be damaged or not. DNA damage values are expressed as a percentage of total cells counted. *Significantly different from control cells incubated without LH, P < 0.05.