The glomus cell of the carotid labyrinth of Xenopus laevis.

The ultrastructure of the glomus cells of the carotid labyrinth was investigated in the anuran, Xenopus laevis. These cells show many catecholamine containing granules. About 50 cells in groups of 3-5 are located near the sinusoids. Morphologically, their organelles are similar to those previously reported in Bufo vulgaris. Striking features are (1) intimate appostion of the glomus cell to smooth muscle (g-s connection), (2) gap junctions between adjacent glomus cells, (3) exocytotic figures. Based on these findings a possible function of the glomus cell is discussed.