Mechanoreceptors – detects a mechanical stimulus (i.e. pressure)
| Type of Neurone | Sensory |
| Location | Dermis (Skin) |
| Size | ~1mm |
| Function | Detect Mechanical Stimuli |
Anatomy
- Found in the deeper layers (Dermis) of the skin primarily fingers, external genitals and soles of feet. Also in tendons, ligaments and joints.
- Approx 1mm diameter
- Contains a single myelinated sensory nerve ending (the end of a neurone)
- Sensory nerve ending is wrapped in lamellae (layers of connective tissue with viscous gel between)
- Blood capillary which surrounds the inner wall of the capsule provides relevant nutrients for optimal cellular function (i.e. glucose, Na, water etc.)
Function
- Stimulation occurs (e.g. tap on the arm)
- Lamellae deforms and press on the sensory nerve ending
- Sensory neurone cell membrane stretches which deforms the stretch-mediated sodium ion channels
- Channel opens and Na+ diffuses into the sensory neurone cell creating a generator potential
- If generator potential exceeds threshold level it will trigger depolarisation of the sensory neurone which will cause an action potential to travel along the axon
- Action potential is taken to CNS where a response will be produced (e.g. feeling the tap on the arm)