Figure 3. Effects of halothane (upper) and isoflurane (lower) on3H-DA release rate stimulated by nicotine (5 x 10 sup -4 M from striatal synaptosomes. Experiments were performed in either the presence (filled triangles) or absence (filled squares) of a desensitizing nicotine concentration (10 sup -7 M). Data (means +/- SD) are expressed in pmol [center dot] mg protein sup -1 [center dot] min sup -1.