Hormonal control of integumentary water-loss: evidence for a novel neuroendocrine system in an insect (Periplaneta americana).

An accelerated water-loss was observed in decapitated individuals, no equivalent increase being obtained following severance of the nervous connectives in the neck. Injection of brain and, to a lesser extent, corpus cardiacum extract resulted in a significant reduction in the rate of loss of water from decapitated individuals. The accelerated water-loss observed following decapitation appeared not to result from significant increase in excretory output or loss of water through the spiracles. It is suggested that integumentary transpiration may be affected by a blood-borne factor, or factors, which originate in the brain and corpus cardiacum.