ATP- and ACh-induced responses in isolated cat petrosal ganglion neurons
Chemoreceptor (glomus) cells of the carotid body are synaptically connected to the sensory nerve endings of petrosal ganglion (PG) neurons. In response to natural stimuli, the glomus cells release transmitters, which acting on the nerve terminals of petrosal neurons increases the chemosensory afferent discharge. Among several transmitter molecules present in glomus cells, acetylcholine (ACh) and adenosine 5â€²-triphosphate (ATP) are considered to act as excitatory transmitter in this synapse. To test if ACh and ATP play a role as excitatory transmitters in the cat CB, we recorded the electrophysiological responses from PG neurons cultured in vitro. Under voltage clamp, ATP induces a concentration-dependent inward current that partially desensitizes during 20-30Â s application pulses. The ATP-induced current has a threshold near 100Â nM and saturates between 20-50Â Î¼M. ACh induces a fast, inactivating inward current, with a threshold between 10-50Â Î¼M, and saturates around 1Â mM. A large part of the population of PG neurons (60%) respond to both ATP and ACh. Present results support the hypothesis that ACh and ATP act as excitatory transmitters between cat glomus cells and PG neurons. Â© 2006 Elsevier B.V. All rights reserved.
|Título según WOS:||ATP- and ACh-induced responses in isolated cat petrosal ganglion neurons|
|Título según SCOPUS:||ATP- and ACh-induced responses in isolated cat petrosal ganglion neurons|
|Título de la Revista:||BRAIN RESEARCH|
|Editorial:||ELSEVIER SCIENCE BV|
|Fecha de publicación:||2007|
|Página de inicio:||60|