[Relationship between reaction of membrane potential and size of glomus cells in rat carotid body during hypoxia].

The membrane potentials (Em) of 85 cultured isolated glomus cells were measured by intracellular recording. The shapes of glomus cells were recorded by microscopic photograph and the cell diameter was measured by micrometer enlarger. The glomus cells with different diameters exhibited two distinct responses to hypoxia. The glomus cells with diameter shorter than 10 microns were depolarized in response to hypoxia, while the cells with diameter over 10 microns were hyperpolarized during hypoxia. Thus, it is sugested that glomus cells may be divided into two functionally different subtypes. Although the smaller glomus cells depolarized more seriously under extreme hypoxia, the degree of hypoxia could not change the original response pattern of glomus cells to hypoxia.