This was exciting, not only had we demonstrated brain cooling, but also the selective nature of this mechanism. At rest, when the arterial blood was at a normal temperature there was no cooling, during exercise cooling returned the blood to a normal temperature sparing the brain from overheating. It is important to understand this brain cooling mechanism in context. About a quarter of the heat generated is lost through lungs. The main loss is through sweating from skin.
Some heat is stored in the body so blood temperature rises.
It is hear that the guttural pouch comes into play and specifically cools the small amount of blood required for brain function. Both the sweating and respiratory heat losses help keep the whole animal cool. The significance of the cooling of the blood flowing over the guttural pouch in whole body terms is minimal. What is accomplished is a specific cooling of the blood entering the brain so that this vital organ is protected from heat stress during extreme exercise. I t is a unclear how this information will be applied to help us in the future.