Abstract
Feedforward control of human thermoregulation by skin sympathetic nerve activitySatoshi IWASE1, Naoki SAWASAKI2, Daisaku MICHIKAMI3, Tadaaki MANO4, Junichi SUGENOYA1, Jian CUI51. Department of Physiology, Aichi Medical University, 2. Department of Surgery, Tokai Hospital3. Ohtsuka Pharmaceutical Co. Ltd.4. Director, Tokai Central Hospital5. Pennsylvania State UniversityTwo ways of thermoregulation has been recognized, feedforward and feedback mechanisms. Feedforward mechanism employs neural afferent pathway, whereas feedback uses convection of the blood stream from the peripheral to the core. We investigated the relation between the microneurographically recorded skin sympathetic nerve activity (SSNA) and the tympanic temperature (Tty) measured as the core. Four exposure conditions, 1) local cold, 2) generalized cold, 3) local heat, 4) generalized warming, were loaded to the subjects and the response of SSNA and Tty were analyzed in time series analysis. The abilities to activate and to suppress SSNA were correlated to the changes in Tty, indicating that the individuals who are excellent in activating/suppressing SSNA are excellent in thermoregulation. The time lag of neural activation in Tty was within 1 min, whereas that of convectional Tty change was approx. 10 min. We concluded that skin sympathetic regulation is critical in rapid thermoregulation in humans. [J Physiol Sci. 2006;56 Suppl:S96]
