Calcium Channel Activation and Neural Output During Hypoxic Chemotransduction in the Carotid Body
Calcium ions play a key role in neural transmission at synapses. When the nerve impulse reaches the pre-synaptic nerve terminal, voltage dependent calcium channels open followed by an influx of calcium ions. This triggers the release of a pre-synaptic neurotransmitter and subsequent binding to its post-synaptic receptor1. Substantial experimental evidence suggests that the neurotransmitters in the carotid body are released from type-I cells during hypoxic chemotransduction3,4. Therefore, it is reasonable to hypothesize that calcium channels in type-I cells of the carotid body must be activated to achieve hypoxic chemotransduction. This hypothesis was tested by administering calcium channel blockers and an agonist to the cat carotid body through an in situ perfusion system.
KeywordsCatheter Acetone Bicarbonate Acetylcholine Verapamil
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