PHYSIOLOGICAL CHARACTERISTICS OF SUPERFICIAL BRANCH OF THE RADIAL NERVE INNERVATING MECHANORECEPTIVE UNITS IN THE HUMAN BODY / 西安交通大学学报(医学版)

ABSTRACT

By means of intraneural microrecording (IN-MR) and intraneural microstimulation (INMS),the characteristics of hairy skin's mechanoreceptiveunits innervated by superficial branch of radial nerve andthe sensations mediated by the nerve were ob-served on the awaking human body. A total of 47mechanoreceptive units were identified, 35 of them(74. 5%) were classified as SA units and 12 ofthem (25. 5%) as RA units, hair-follicle unit andPC unit were not found in experiments. The aver-age mechanical thresholds of SA units were some-what higher than those of RA units, receptivefields of RA and SA Ⅰ units were significantlysmaller than those of SA Ⅱ units. The type of unitexcited by INMS determined the sensations quali-y, RA units evoked intermittent tapping, SA Ⅰ u-nits evoked sustained pressure; SA Ⅱ units evokedno particular sensation when activated in isolation.The results indicate that the characteristics of themechanoreceptive units in the hairy skin do not differ from those in the glabrous skin at the humanbody.