Dantrolene reduces the threshold and gain for shivering.

Abstract

UNLABELLED: Dantrolene is used for treatment of life-threatening hyperthermia, yet its thermoregulatory effects are unknown. We tested the hypothesis that dantrolene reduces the threshold (triggering core temperature) and gain (incremental increase) of shivering. Healthy volunteers were evaluated on 2 random days: control and dantrolene (approximately 2.5 mg/kg plus a continuous infusion). In Study 1, 9 men were warmed until sweating was provoked and then cooled until arteriovenous shunt constriction and shivering occurred. Sweating was quantified on the chest using a ventilated capsule. Absolute right middle fingertip blood flow was quantified using venous-occlusion volume plethysmography. ..