Receptor potential, a type of graded potential, is the transmembrane potential difference of a sensory receptor.
A receptor potential is often produced by sensory transduction. It is generally a depolarizing event resulting from inward current flow. The influx of current will often bring the membrane potential of the sensory receptor towards the threshold for triggering an action potential.
A receptor potential is a form of graded potential. An example of this is in a taste bud, where taste is converted into an electrical signal sent to the brain. When stimulated, the taste bud triggers the release of neurotransmitter through exocytosis of synaptic vesicles from the presynaptic membrane. The neurotransmitter molecules diffuse across the synaptic cleft to the postsynaptic membrane.
Graded potentials vary in size. They arise from the summation of the individual actions of ligand-gated ion channel proteins, and decrease over time and space. They do not typically involve voltage-gated sodium and potassium channels.
Famous quotes containing the words receptor and/or potential:
“The disinterest [of my two great-aunts] in anything that had to do with high society was such that their sense of hearing ... put to rest its receptor organs and allowed them to suffer the true beginnings of atrophy.”
—Marcel Proust (18711922)
“Not many appreciate the ultimate power and potential usefulness of basic knowledge accumulated by obscure, unseen investigators who, in a lifetime of intensive study, may never see any practical use for their findings but who go on seeking answers to the unknown without thought of financial or practical gain.”
—Eugenie Clark (b. 1922)