Cholinergic Dimensions to Carotid Body Chemotransduction
Prevalent current opinion depicts the basic chemoreceptive unit in the carotid body as a glomus or Type I cell being a storehouse of several neurotransmitters; apposed to it is a neuron, properly called a dendrite, whose cell body is in the petrosal ganglion and whose axon terminates in nucleus tractus solitarius. Prevalent current opinion describes hypoxic chemotransduction in the following steps: (a) Hypoxia by some mechanism, perhaps involving a change in the configuration of a membrane protein, depolarizes the glomus cell, perhaps by altering the conductance of an ion channel in the membrane; (b) Extracellular calcium enters the glomus cell; (c) One or more excitatory neurotransmitters is released into the synaptic cleft between the glomus cell and the apposed neuron; (d) The neurotransmitter binds to a postsynaptic receptor; (e) An action potential is initiated in the neuron. OUR HYPOTHESIS: ACETYLCHOLINE IS AN ESSENTIAL EXCITATORY NEUROTRANSMITTER IN THE PROCESS OF HYPDXIC CHEMOTRANSD UCTION.
KeywordsDopamine Bicarbonate Acetylcholine Nism Atropine
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