SUBCUTANEOUS NORADRENALINE CONCENTRATION INCREASE IN NORMAL SUBJECTS DURING COLD-EXPOSURE EVALUATED BY MICRODIALYSIS

Changes in local noradrenaline level in subcutaneous tissue were measu red in four healthy males (23-33 years) during cold stimulation using a microdialysis technique. The subcutaneous dialysate noradrenaline co ncentration increased during cold exposure by a factor of 3.5 (P<0.003 ). A correction factor due to plasma overflow of noradrenaline to subc utaneous tissue was calculated from noradrenaline infusion studies. Th is correction had a minimal effect on the observed increase in dialysa te noradrenaline concentration and the level of significance was only slightly altered after correction for plasma overflow. The microdialys is technique in combination with a sensitive radioenzymatic noradrenal ine assay may be useful to assess changes in local subcutaneous noradr enaline level in man during physiological stimulation.