[Sensitive innervation of the skin of the concha auriculae]

By means of the retrograde transport of horseradish peroxidase (HP) method sensitive innervation of the rabbit concha auriculae skin has been studied. For the investigation the skin area 2 X 2 sm large has been chosen on the internal surface of the right concha auriculae 6 sm below the upper edge of the ear. The HP solution is injected in the skin areas 5-6 mm large with normal electrical permeability and with decreased electrical resistance to the constant electrical current. In the first case innervation is ensured only by ipsilateral sensitive neurons of the spinal nodes (SN) CIII. Small neurons make 75% of the total amount of the labelled cells. In the second case about 98% of the skin areas are innervated by the neurons of the SN CIII and about 2% by the neurons of the SN CII. Small and middle neurons make 60% and 38%, respectively. Single labelled cells are revealed in the SN CIV. The HP-positive neurons, innervating the skin areas with an increased electrical permeability nearly 3 times exceed the neurons, projecting on the skin areas with normal electrical permeability. The large labelled neurons make 2% in both cases. Localization of the HP-positive cells in the SN is diffuse, structural compositions of the neurons are not revealed. In the trigeminal node labelled neurons are not found.