Lack of effect of adrenal denervation on analgesia elicited by continous and intermittent cold water swim in the rat

The present experiment was conducted to determine if continuous and/or intermittent cold water swim analgesia is dependent upon a factor released from the adrenal medullae. Male Sprague-Dawley rats (300-350 g) underwent either bilateral adrenal denervation or sham surgery and two weeks later were exposed to continuous (3.5 m) or intermittent (10 s in, 10 s out for 6 min) swim in water at 4 degrees C. Adrenal denervation failed to affect either intermittent or continuous cold water swim analgesia. It was concluded that both types of cold water swim analgesia are independent of adrenal medullary function.