Progesterone-Induced Acrosome Reaction: DISCUSSION(6)
These non-viable spermatozoa remained P-BSA-FITC positive, probably due to postacrosomal cytosolic staining (see Figs. 1C and 3B). Although a slightly higher proportion of P-BSA-FITC spermatozoa was determined with the flow cytometer in comparison with the fluorescence microscopy observation, the differences were smaller than 3-6%. It should be mentioned that P-BSA-FITC-stained sperm samples were analyzed as fixed samples for the fluorescence microscopy but were not fixed for analysis with the flow cytometer. buy flovent inhaler
This may explain the small differences observed. Furthermore, the flow cytometer cannot distinguish between different localization patterns of P-BSA-FITC but only discriminates between the intensity of P-BSA-FITC bound to individual sperm cells. The difficulty in distinguishing the actual staining patterns was probably due to a variability in the intensity of fluorescence emitted by a unit area of sperm surface, as related to the receptor density per unit area. It is therefore possible that some spermatozoa weakly stained with P-BSA-FITC were determined to be positive using flow cytometry but negative using fluorescence microscopy due to difference in sensitivity of the FL-1 detector compared to the naked eye.