Final Considerations on the Chemoreceptor Complex

The evidence presented above indicates that the presence of glomus cells is a requisite for hypoxic chemoreception. However, some limitations in the interpretation of the above considerations must be presented here  

That glomus cells exhibit membrane and cytoplasmic changes in response to hypoxia is very well documented (see Refs. 52-54), but the only way to demonstrate that hypoxia-induced glomus cell excitation initiates the full chemoreceptor process is by recording sensory discharges from the adjacent nerve fibers. 

Local destruction of glomus cells is commonly accompanied by elimination—or at least dedifferentiation—of sustentacular cells, whose actions have seldom been searched for and whose importance is poorly understood. 

Elimination of glomus cells suppresses not only their transduction mechanisms for natural chemical stimulation but also their possible trophic effects upon adjacent sensory nerve endings. 

Destruction of the parenchymal cells of the carotid body (both glomus and sustentacular cells)—by either cryocoagulation or by hgature-induced ischemia— is accompanied by a profound distortion of the rich vascularization of the carotid body, whose consequences may contribute to the abohtion of the hypoxic chemoreception observed. 

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