Peripheral chemoreceptors respond to
hypoxia using which channel?
a) Calcium channel
b) Sodium channel
c) Potassium channel
d) Chloride channel
Correct Answer - C
Ans: C. Potassium channel.
Carotid bodies are composed of glomus cells (also called type I),
which are of neuronal phenotype and contain a variety of
neurotransmitters.
Glomus cells are in functional contact with the afferent nerve
endings.
Glomus cells are initial site(s) of sensory transduction.
Hypoxia releases transmitter(s) from glomus cells, which in turn by
depolarizing the sensory nerve ending leads to an increase in
sensory discharge.
One hypothesis assumes that a K±channel protein is an O2 sensor
and that hypoxia depolarizes glomus cells by inhibiting the K+
channel, leading to an increase in cytosolic Ca2+, resulting in
transmitter(s) release