Figure 2.

Reversibility of nerve-evoked twitch blockade produced by candoxin. (a) Segments of tracing showing the complete blockade of nerve-evoked twitches of the chick biventer cervicis muscle produced by candoxin (100 μg ml⁻¹; 13.6 μM). Candoxin was washed out at the point indicated. (b) Neostigmine (1 μM) was added to the bath at the point indicated. The vertical bar represents the magnitude of the twitch response in g tension. The horizontal bar depicts the time in min. The figures are representative of six experiments. (c) Comparison of the time to full recovery from complete blockade of nerve-evoked twitch responses produced by various concentrations of candoxin in the chick biventer cervicis muscle (n=6), mouse phrenic nerve hemidiaphragm (n=4) and GPD (n=4). Candoxin was washed out immediately following the establishment of complete twitch blockade. The time required for the restoration of nerve-evoked twitch responses to 100% of control twitch height is shown. (d) Comparison of the time to full reversal of blockade of nerve-evoked twitch responses produced by candoxin (100 μg ml⁻¹; 13.6 μM) following the addition of various concentrations of neostigmine. Neostigmine was added 5 min after complete twitch blockade was established. Data is the mean of four experiments for all tissues. Vertical bars represent the s.e.m.