Fig. 7. Action potential (AP) distribution in responses to stimulation with 10 µg bombykal. Post-stimulus-time histograms (binwidth=10 ms) for recordings from ZT 8-11 for the beginning (A; 0-20 min), middle (B; 80-100 min) and end of the recordings (C; 160-180 min). Both in the controls (left) as well as under the influence of 8bcGMP (right) the first phasic part of the AP response declined, leading to a more tonic response. Also, the numbers of APs over the first 100 ms (insert in C) showed a significant decrease both with 8bcGMP and in the controls. This decline was stronger in the presence of 8bcGMP. Since the sample sizes differed for the different time windows all y-axes were scaled to y=nx1.6 (dotted line=100 ms after the onset of the sensillar potential). Different lower case letters in the inserts denote significant differences between tested groups of means, which are separated by dotted lines (ANOVA and Tukey HSD post-hoc-test; =0.01, P<0.01).