Summary
The carotid body of the rat consists of “glomera” interspersed by blood vessels and nerve bundles. Each “glomus” consists of 2–12 Type I cells, incompletely invested by 1–3 Type II cells. Type I cells are characterised by the presence of numerous dense cored vesicles in their cytoplasm and may exhibit “synaptic”-like contacts with each other.
Small efferent nerve endings make synaptic contact with one or more Type I cells. Large cup-shaped afferent nerve endings make multiple synaptic contacts of two kinds with one or more Type I cells. A second kind of efferent nerve ending is occasionally seen in synaptic contact with one of these afferent nerve endings.
A model for the mode of operation of the glomus as a chemoreceptor is proposed.
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This study was supported by a Research Fellowship from the British Heart Foundation (Miriam Morgan) and a Science Research Council Studentship (R. J. Pack).
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Morgan, M., Pack, R.J. & Howe, A. Nerve endings in rat carotid body. Cell Tissue Res. 157, 255–272 (1975). https://doi.org/10.1007/BF00222070
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DOI: https://doi.org/10.1007/BF00222070