Figure 3.
Characterization of the mannitol- and angiotensin II-induced potentiation of mEPSCs. A, Representative examples of the effect of AM251, a cannabinoid type 1 receptor blocker, on the mannitol- and angiotensin II-induced potentiation of mEPSC. a, Mannitol; b, angiotensin II. The holding potential was −70 mV. Plots of frequency are single measurements, whereas plots of amplitude are mean ± SEM over 30 s. B, Summary data for the characterization of mEPSCs under mannitol and angiotensin II application. a, Frequency (left) and amplitude (right) of mEPSCs. mannitol (n = 8), mannitol plus AM251 (n = 8), mannitol plus PMP-AVP (n = 6), mannitol plus atosiban (n = 6) and mannitol (fluorocitric acid) (n = 5), respectively. b, Angiotensin II (n = 8), angiotensin II plus AM251 (n = 6), angiotensin II plus PMP-AVP (n = 4), angiotensin II plus atosiban (n = 6) and angiotensin II (fluorocitric acid) (n = 4). Data are mean ± SEM. *p < 0.05, compared with mannitol or angiotensin II. C, Mannitol-induced potentiation of mEPSCs is extracellular Ca2+ dependent. a, A representative example of the effect of mannitol (60 mm) on mannitol-induced potentiation of mEPSCs in the Ca2+-free perfusion medium. b, Summary data for the effects of mannitol on frequency (left) and amplitude (right) of mEPSCs in normal solution (n = 8) and in Ca2+-free solution (n = 8). Data are mean ± SEM. **p < 0.01, compared with no treatment.