Axon reflexes in human cold exposed fingers

Exposure of fingers to severe cold induces cold induced vasodilation (CIVD). The mechanism of CIVD is still debated. The original theory states that an axon reflex causes CIVD. To test this hypothesis, axon reflexes were evoked by electrical stimulation of the middle fingers of hands immersed in water at either 5°C or 35°C. Axon reflexes were...

Axon Reflexes in cold-exposed fingers

Prolonged immersion of fingers in cold water induces Cold-Induced Vasodilatation (CIVD). Although evidence is available that Arterio-Venous Anastomoses (AVAs) play an important role, the mechanism underlying CIVD remains unsolved. The main hypotheses are a paralysis of the AVAs due to an impaired neuromuscular transmission (I) and the occurrence...

Finger cold-induced vasodilatation during hypothermia, hyperthermia and at thermoneutrality

BACKGROUND: Exposure of the fingers to severe cold leads to cold-induced vasodilation (CIVD). The influence of ambient temperature on the CIVD-response is well understood and documented, but the response of CIVD to hyperthermia and mild hypothermia has rarely been investigated. METHODS: To investigate the influence of body thermal status on the...

Physiological responses of the human extremities to cold water immersion

Five subjects immersed their hands and feet twice during 1 hour sessions in a calorimeter bath, filled with water at 25 degrees C. Before immersion the hand (33.0 +/- 2.2 degrees C) was warmer than the foot (30.6 +/- 2.1 degrees C) and so was the blood flow: respectively 5.8 +/- 5.2 versus 0.7 +/- 0.3 ml.min-1.100 mo tissue-1 as determined by...