Fig. 15.
APGWamide decreases the excitability of B20 and B4/5 in a concentration-dependent manner. Depolarizing current pulses (3 sec duration) were injected into B20 (A) and B4/5 (B) every 60 sec. APGWamide was applied in ascending concentrations (from 10−7 to 10−5m).A, Examples from experiments that were performed in normal saline (1) and in high-divalent saline (2). The application of APGWamide reduced the excitability of B20 in a concentration-dependent manner (fromleft to right, 40, 24, 12, 0, and 33 spikes in1; 28, 22, 12, 0, and 19 spikes in 2). B20 spiking showed almost complete recovery in normal saline (1) and only partial recovery in high-divalent saline (2) after peptide washout.B, B4/5 excitability was reduced by APGWamide in a concentration-dependent manner (from left toright, 24, 18, 6, 0, and 24 spikes). B4/5 spiking recovered completely after peptide washout. Experiments were performed in normal saline.