Figure 5.

Cutaneous vascular conductance (CVC) measured at three times during rapid STEP heating: at baseline before heating (averaged over the 5 min prior to heating), at the peak of the initial response, and at a plateau of the sustained response after 30 min maintained at 42°C (averaged over the last 5 min of this period). The effect of cigarette smoking on these values is shown in A, and that of nicotine nasal spray in B, both in separate sites not treated (n = 8 for cigarettes and n = 9 for nasal spray) and treated with bretylium via iontophoresis (n = 5 for cigarettes and n = 6 for nasal spray). Values are means ±s.d. and are expressed as a percentage of the reference CVC for that site. * Significant difference from before nicotine administration, signed-rank test, P < 0.05.