CYTOCHEMICAL DEMONSTRATION OF SUBTYPES OF TYPE-I CELLS IN THE RABBIT CAROTID-BODY CHEMORECEPTOR

Samples of carotid bodies from control and reserpinized rabbits were i ncubated in a sodium chromate and potassium dichromate buffer after pr imary glutaraldehyde fixation. Such a cytochemical staining method cou ld show that the reserpine treatment resulted in a decrease in the ele ctron density of the densecored vesicles to a different degree in diff erent subtypes of Type I cells. The decrease was moderate in subtype B cells, obvious in subtype C cells, and invisible in subtype A cells. The present work offered a morphofunctional evidence for the existence of subtypes of Type I cells, and gave a hint that the different subty pe cells may store different catecholamines.