Average values of the synapto-pHluorin responses to stimulation as well as the initial rate of post-stimulus synapto-pHluorin decay (endocytosis rate)
Synapto-pHluorin responses were measured over an 8-s period for three different stimulation conditions in each cell (mean ± S.E.M., n = 4 cells). Isoflurane (0.95 ± 0.03 mM) led to a 42 ± 1.7% reduction in peak response (p < 0.05 by paired t test) and a 51 ± 3.4% reduction in endocytosis rate (p < 0.05 by paired t test) at a stimulus frequency of 10 Hz. At a lower stimulus frequency (6.8 Hz), where the peak response matched that for 10-Hz stimulation in isoflurane, endocytosis was identical (p > 0.05 by paired t test).