Sympathetic neurogenic control of blood flow in human nasal mucosa.

Nasal mucosal blood flow was investigated in patients undergoing a stellate ganglion blockade. Elimination of the sympathetic neurogenic control did not affect the resting blood flow in the mucosa, as registered with the 133Xe washout technique. This indicates that the basal sympathetic vasoconstrictor activity is low in the mucosal vessels that regulate blood flow. With laser doppler flowmetry, the normal pattern of spontaneous oscillations in blood flow was seen to be altered following stellate ganglion blockade. This suggests that vasomotion in the mucosa is partly dependent on sympathetic neurogenic activity. Furthermore, the decrease in blood flow normally induced by a peripheral cold provocation could not be elicited after the ganglion blockade, which means that the decrease is mediated by sympathetic vasoconstrictor fibres.