[Histochemical study of the chemoreceptor function of the carotid body in comparison with the superior cervical ganglion].

The distribution and relative activities of some dehydrogenases and diaphorases in the rat's carotid body and ganglion cervicale superior were studied histochemically and cytophotometrically. The treatment of rats by the medium with decreased oxygen and increased carbon dioxide contents, a reliable rise of NAD--diaphorase activities was found in the interlobe tissue and (less expressed and late appearing) in the principal cells. In contrast, such changes were not observed in the ganglion cervicale superioir, that have not a special chemoreceptory function. It is supposed that these changes in enzyme activities in the carotid body is due to the chemoreceptory function of the intralobe tissue containing the IInd type cells and "special" cells of sensitive nerve terminals.