AJP - Cell Physiology, Vol 263, Issue 6 C1152-C1159, Copyright © 1992 by American Physiological Society
Characterization of cultured chemoreceptor cells dissociated from adult rabbit carotid body
M. T. Perez-Garcia, A. Obeso, J. R. Lopez-Lopez, B. Herreros and C. Gonzalez
Departamento de Bioquimica y Biologia Molecular y Fisiologia, Facultad de Medicina, Universidad de Valladolid, Spain.
Short-term cell cultures were obtained from enzymatically dissociated
carotid bodies from adult rabbits, and morphological and functional
characterization of the cultured chemoreceptor cells were carried out.
Under phase contrast, freshly isolated type I cells are round, bright, and
10-14 microns in diameter and exhibit strong fluorescence when stained with
the glyoxylic acid technique. The content of endogenous dopamine in the
cultures increased from 80 pmol/10(5) cells 2 h after plating the cells to
200 pmol/10(5) cells on the 3rd day, and the rate of synthesis and storage
of [3H]dopamine from the precursor [3H]tyrosine increased from 1.7
pmol.10(5) cells-1.h-1 in 1-day cultures to 4 pmol.10(5) cells-1.h-1 on the
3rd day; the later values represent 80-85% of the expected values for the
intact carotid body. After labeling with [3H]tyrosine, cultured
chemoreceptor cells release [3H]dopamine when challenged by hypoxia, high
external K+, or the protonophore dinitrophenol, the pattern of response
being similar to that of the intact carotid body. When studied by whole
cell clamp recording, individual chemoreceptor cells exhibit a marked
variability in the properties of some ionic currents; the data, however, do
not support the existence of distinct subpopulations of type I cells.
