Vater-Pacini corpuscles

Vater-Pacini corpuscles, also known as Pacinian corpuscles, are one of the four major types of mechanoreceptors found in the skin. They are responsible for sensing pressure and vibration. Named after their discoverers, Abraham Vater and Filippo Pacini, these sensory receptors are located in both the dermal and subcutaneous layers of the skin, as well as in various internal organs. They play a crucial role in the sensory system of humans and many other animals.

Structure

Vater-Pacini corpuscles are oval-shaped and consist of a central nerve ending surrounded by concentric layers of connective tissue, resembling an onion. These layers act as a filter, allowing the corpuscle to detect rapid vibrations and pressure changes. The central nerve fiber is a part of the peripheral nervous system and is connected to the larger sensory neurons that relay information to the brain.

Function

The primary function of Vater-Pacini corpuscles is to sense mechanical stimuli, specifically vibrations and pressure. They are most sensitive to vibrations between 10 and 50 Hertz. When pressure is applied to the skin, it deforms the layers of the corpuscle, causing a mechanical stimulus that activates the nerve ending. This activation generates a nerve impulse that is transmitted to the brain, where it is interpreted as touch or vibration.

Location

Vater-Pacini corpuscles are widely distributed throughout the human body. They are most abundant in areas sensitive to vibration, such as the fingertips, soles of the feet, and external genitalia. They are also found in the pancreas, where their function is not entirely understood.

Clinical Significance

The sensitivity of Vater-Pacini corpuscles can decrease with age, leading to a diminished sense of touch and vibration. Additionally, certain medical conditions, such as diabetes mellitus, can affect their function, contributing to the development of peripheral neuropathy. Understanding the role and health of these corpuscles is important in diagnosing and treating sensory disorders.

See Also

• Mechanoreceptor
• Sensory system
• Skin
• Peripheral nervous system