2013 Sensory Physiology

Receptor potentials

Critical Fact IconA receptor potential is a graded response to a stimulus that may be DEPOLARIZING or HYPERPOLARIZING. Receptor potentials have a threshold in stimulus amplitude that must be reached before a response is generated, and their amplitude saturates in response to intense stimuli.

  • graded means the amplitude of the receptor potential is proportional to the size of the stimulus

  • the transduction process couples stimulus detection (i.e., activation of a receptor protein) to the opening or closing of ion channels

    • the nature of receptor proteins, and how they are coupled to ion channels, is different in each sensory system
    • the transduction channels are often non-selective (typically resulting in the transduction current being carried by Na+, but sometimes by other ions)
    • for example, compare the nature of the different types of transduction channels in the somatosensory system
Receptor potential properties

 

 

 

Email: Dr. Janet Fitzakerley | ©2013 University of Minnesota Medical School Duluth | Last modified: 6-feb-13 10:03 PM