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Which chemicals are stored in vesicles within carotid body type I cells?
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Chemoreception
Animals, such as this pine grosbeak, use chemoreception to respond to chemicals that can be tasted and smelled in their environments. Many of these chemicals affect behaviors such as food preference and defense.
Type I cells within the carotid body contain electron-dense vesicles that store several neuroactive substances. These chemicals include:
- Acetylcholine1
- Catecholamines1
- Neuropeptides, specifically:
- Enkephalins1
- Vasoactive intestinal polypeptide1
- Substance P1
It is believed that when these cells are stimulated by hypoxia or hypercapnia, they release one or more of these substances to act upon the sensory nerve fibers involved in chemoreception.1