Hypothermia and acetylcholine content of dog heart.

The acetylcholine level of dog heart has been determined under hypothermia. It was increased at 28 degrees C, and decrease at 20 degrees C. Further, it was observed that the heart rate and blood pressure decreased with gradual reduction in the body temperature of the dog and ventricular fibrillation occurred in 50% of the animals at 20 degrees C. It is proposed that cholinergic agents may have a role as antifibrillatory agents in hypothermia.