PHASIC CHANGES IN HUMAN NASAL AND SKIN BLOOD-FLOW - RELATIONSHIP WITHAUTONOMIC TONE

To assess the autonomic control of the microcirculation in human skin and nasal mucosa, the spontaneous fluctuations of a laser Doppler sign al recorded on forearm skin and nasal mucosa were compared with heart rate fluctuations and the respiratory signal in 11 healthy subjects by means of spectral analysis. Possible direct mechanical-thermal effect s of airflow on the nasal mucosa were evaluated by comparing recording s obtained when the subjects were breathing through either the nose or the mouth. Comparison of the spectral analysis of the signal obtained for skin and nasal mucosa blood flow allowed us to define the charact eristics of the autonomic tone of the microcirculation in these two ar eas. The skin is mainly influenced by sympathetic activity, and the na sal blood flow is regulated by both sympathetic and parasympathetic ac tivity.