DENERVATION IMPAIRS CUTANEOUS MICROVASCULAR FUNCTION AND BLISTER HEALING IN THE RAT HINDLIMB

SKIN sensory nerve nocifensor functions were investigated non-invasive ly in rats by measuring neurogenic inflammation and blister healing-ra te after unilateral hindlimb denervation. Axon reflexes were evoked by transdermal iontophoresis of acetylcholine (ACh) or noxious electrica l stimulation (TNS). Sodium nitroprusside (SNP) evoked direct dilator responses. Resultant changes in skin microvascular blood flux were mea sured by laser Doppler flowmetry. Compared with their sham-operated co ntrol limbs, denervation reduced inflammatory responses (ACh or TNS) b y more than 85% and SNP responses by 28% (p < 0.05). Healing of dry-ic e blisters raised on the hindpaw 14d post-denervation was significantl y slower to complete healing (42d) than controls (26d) and initial inf lammation was attenuated, confirming that innervation is important for inflammation and blister-healing.