Fig. 2.
Flow cytometric analysis of epididymal rat spermatozoa stained with 5-(and-6)-carboxy-2′,7′-dichlorodihydrofluorescein diacetate (carboxy-H2DCFDA) and propidium iodide (PI). (a, b) Dot plot cytograms before (a) and after (b) stimulation with tert-butyl hydroperoxide (TBHP). In these cytograms, the lower quadrants represent viable (PI−) spermatozoa and the upper quadrants represent dead (PI+) spermatozoa. (c, d) Intracellular reactive oxygen species levels in spermatozoa were evaluated according to mean DCF fluorescence intensity (DCFMFI) before (open) and after stimulation (shaded) with TBHP in total (c) and viable (d) sperm populations.