Figure 1

This figure showed a videoimage of NO-associated fluorescent intensity taken from cremasteric arteriole of a young rat by using 20 ×-objective lenses. From 14 frames of working windows, the Histogram Menu in Image Program Software was used to define the mean value of fluorescent intensity of each window, and then the averaged intensity was calculated for all 14 small working window frames (7 × 3 μm² each window). The intensity difference (I_diff) between the averaged intensities obtained at 20 min (I_{20 min}) and at baseline (I_{0 min}) were calculated and represented by the percentage change in intensity from its baseline value, using the following equation: %Change of NO-associated fluorescent intensity = (I_{20 min}- I_{0 min}/I_{0 min})×100