Table 1.

Effect of GVIA and MVIIC on whole contraction

StimulusGVIA IC50(nm)MVIIC IC50 (nm)Maximum % inhibition by GVIAMaximum % inhibition by MVIIC
5 Hz3020053.4  ± 6.6683.4  ± 5.50
10 Hz3020054.8  ± 5.2685.5  ± 3.74
20 Hz12522548.6  ± 4.0880.1  ± 6.99
50 Hz>100047036.3  ± 2.8876.1  ± 4.06
  • The concentration of toxin required to reduce the amplitude of bladder dome contractions by 50% was interpolated from graphs of toxin concentration versus response at a particular frequency. These values are listed for GVIA and MVIIC in columns 2 and 3. The maximum inhibition produced by GVIA, obtained at concentrations >30 nm, is shown in column 4. The maximum effect of MVIIC obtained in these experiments, at a concentration of 3 μm, appears in column 5. Each calculation is based on the results of eight experiments on preparations from different animals.