Premium
Botulinum toxin A inhibits sweat secretion via a post‐synaptic mechanism
Author(s) -
Shibasaki Manabu,
Davis Scott L,
Cui Jian,
Low David,
Keller David M,
Crandall Craig G
Publication year - 2006
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.20.5.a1245
Botulinum toxin A (BOTOX) disrupts neurotransmitter release from cholinergic nerves. Interestingly, the effective duration of BOTOX in impairing sweat secretion is greater relative to its effect in impairing muscle contraction, suggesting possible different mechanisms in these tissues. The aim of this study was to investigate the effects of BOTOX on sweating to exogenous administration of acetylcholine. BOTOX was injected in dorsal forearm skin at least three days before assessment. On the experimental day intradermal microdialysis probes were placed at the BOTOX site and an adjacent untreated site. After a minimum of 90 min following microdialysis probe placement, incremental doses of acetylcholine were administered through the microdialysis membranes while sweat rate was assessed (protocol 1; n=6) or while a combination of sweat rate and skin blood flow were assessed (protocol 2; n=7). Local skin temperature was controlled at 38°C in protocol 1 and at 34°C in protocol 2. Appropriate sweating was observed at the control site for both protocols; however, there was an absence of sweating at the BOTOX site. Cutaneous vascular conductance increased to a similar level between BOTOX and control sites (4.6±2.0 versus 4.2±1.0 AU/mmHg), although the dose‐response curve was slightly shifted to higher acetylcholine concentrations at the BOTOX site. These results suggest that BOTOX is capable of inhibiting sweat secretion via a post‐synaptic mechanism without appreciably altering acetylcholine‐mediated cutaneous vasodilation. Project funded by NIH HL67422, HL 61388, and GM68865