Vasodilatory response of arteriovenous anastomoses to local cold stimuli in the dog's tongue.

In anesthetized dogs total tongue blood flow and its distribution to mucosa and muscle capillaries and to arteriovenous anastomoses (AVA) was determined by combining venous outflow measurements with the radioactive microsphere technique. Local temperature changes of the tongue surface in the physiological range revealed an inverse relationship between lingual blood flow (8.6--30.4 ml . min-1) and tongue surface temperature (40.5 to 27.7 degrees C). The temperature dependent changes of tongue blood flow were exclusively due to changes of AVA blood flow (6.3--21.4 ml . min-1).