Evaluation of direct and axon reflex sweating in the mouse

The nicotinic axon reflex-mediated sudomotor response was studied in mice a nd rats by recording the impressions of sweat droplets made in silicone mol ds after local injection of nicotine, and compared with sweating induced by acetylcholine and pilocarpine. Nicotine failed to activate mouse plantar s weat glands at any of the concentrations used (from 3 X 10(-6) to 3 X 10(-1 ) M). On the contrary, both acetylcholine and pilocarpine produced a dose-d ependent increase in the number of secreting sweat glands. The location of sweat glands reactive to pilocarpine and acetylcholine was similar and rest ricted to the pads near the site of injection. We conclude that the sudomot or axon reflex response mediated by nicotinic receptors is not present in t he mouse and the rat. (C) 2000 Elsevier Science B.V. All rights reserved.