Short of air? Cool it!

摘要

In this issue of The Journal of Physiology, in an elegant series of experiments on chronically instrumented ground squirrels, Tattersall & Milsom (2009) now demonstrate that both the threshold and the gain of the metabolic response to directly cooling the preoptic area with an implanted thermode are substantially reduced when the animals breathe hypoxic gas. This finding demonstrates clearly that there is a regulated shift in the body's metabolic response to cooling, mediated both by shivering and by non-shivering thermo-genesis, driven by temperature detectors in the brain. While the phenomenon has been studied before, by delving into the 'black box' these new findings speak directly to the neural mechanisms.