Anatomy & Organs

Father Pacini Bodies – Structure, Function & Diseases

Father Pacini bodies

Vater-Pacini corpuscles belong to the mechanoreceptors in the skin that are particularly suitable for detecting vibrations. A thickening serves as a sensor. There is a thickening at the unmyelinated ends of the otherwise medullated nerves , which can reach a diameter of up to 2 millimeters. The thickening consists of 40 to 60 concentric layers of lamellae, which are surrounded on the outside by a connective tissue capsule.

What is the Father Pacini body?

Vater-Pacini corpuscles are named after the German anatomist Abraham Vater (18th century) and the Italian anatomist Philippo Pacini (19th century). Together with 4 other types of mechanoreceptors, they belong to the tactile sensors, of which each type is optimized for the detection of specific stimuli.

The father-Pacini corpuscles are the only tactile sensors in the hypodermis (subcutis) because they can cover a relatively wide field according to their specialization. They adapt quickly, which means they specialize in rapid changes in stimuli. Their main task is the sensory detection of vibrations. Due to their extremely fast adaptation, they are optimized for vibrations in the frequency range of 300 Hz (oscillations per second), a frequency that is already perceived by the human ear as a low-pitched tone.

The sensory head of the Vater-Pacini corpuscles consists of a thickening at the unmyelinated nerve endings of afferent neurons, which are otherwise surrounded by a myelinated sheath. Father-Pacini corpuscles are found in the palms of the hands and soles of the feet as well as on the fingertips. Further accumulations are found in the periosteum , in the pancreas , in other organs of the lower abdomen, in the urinary bladder and in the vaginal area.

Anatomy & Structure

Father-Pacini corpuscles mark the unmyelinated terminal part of sensory nerves, which are surrounded by a myelinated sheath the rest of their course. The Vater-Pacini corpuscles consist of a thickening of the nerve endings, which arise from a concentric – onion-skin-like – layering of up to 60 lamellae.

The lamellae consist of flattened Schwann cells that normally envelop unmyelinated neurons. The individual lamellae are each separated from one another by an extremely thin film of interstitial body fluid. Inside the sensor heads is a fluid-filled space in which the free end of the nerve can move. On the outside, the tactile bodies are surrounded by a connective tissue capsule. The anatomical structure of the Vater-Pacini corpuscles makes them very quickly adapting tactile sensors.

A deformation of just a few micrometers already causes an influx of sodium ions that trigger an action potential. The sensors hardly react to slow deformations that last longer. They specialize in rapidly changing compression deformations that typically occur with vibrations.

Function & Tasks

Together with Merkel cell receptors, Krause corpuscles, Meissner corpuscles and Ruffini corpuscles, Vater-Pacini corpuscles form a composite of skin sensors known as the sense of touch. In order to convey a more complete picture of the responsible brain areas, the sense of touch is supplemented by temperature and pain sensors. The brain is not only able to create a picture of the situation from the millions of sensor reports, but the received and processed reports can also be converted into conscious or unconscious instructions for action.

For example, high temperature reports lead to an unconscious opening of the skin’s sweat pores in order to intensify the evaporative cooling for a cooling effect. Father Pacini corpuscles are specialized in rapid pressure changes and changes in the direction of the pressure effects, so that they can perceive vibrations very well. You can even detect weak vibrations up to several hundred vibrations, i.e. vibrations that are already far into the audible range, which starts at around 200 Hz. Father Pacini corpuscles respond not only to vibrations applied to the skin from the outside, but also to changes in pressure on the skin when hands slide over a rough surface.

This means that they not only serve as part of a warning device against possible imminent injuries, but are also part of the sense of touch for better haptic detection of a surface. At the same time, they complement the fine sensory detection of lightweights such as spiders and insects that crawl over the skin and can potentially become dangerous.

Diseases

As with all sensory performances, which are recorded by the formation of nerve action potentials and are passed on in the form of electrical impulses via ganglia and other “clearing points” such as the thalamus , functional disorders can also occur in the father-Pacini bodies.

A reduced performance of the tactile corpuscles can be due to mechanical injuries in the affected skin areas or to infections or tumors that lead to serious physiological changes. Much more frequently, however, the transmission paths of the nervous impulses, i.e. the neurons themselves or the conversion of the nervous impulses at the synapses, are affected. Only rarely are disturbances in surface sensitivity limited to Pacini bodies. As a rule, such disturbances extend to all skin sensors in a certain area. The perceptual sensation can refer not only to a weakening ( hypaesthesia ), but also to an increase ( hyperaesthesia ) of the sensations.

Weakening of the surface sensitivity can often be observed, which can often be attributed to circulatory disorders (ischemia) and thus to a lack of supply to the afferent sensory nerves. Ischemias in this area are often indicators of serious metabolic disorders such as diabetes . In addition to metabolic disorders, hypaesthesia up to complete numbness (numbness) can also be caused by mechanical pressure exerted on the nerves. The mechanical pressure can typically arise at constrictions that serve the passage of nerves and blood vessels to joints such as the carpal tunnel in the wrist .

Lisa Newlon
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Hello! I am Lisa Newlon, and I am a medical writer and researcher with over 10 years of experience in the healthcare industry. I have a Master’s degree in Medicine, and my deep understanding of medical terminology, practices, and procedures has made me a trusted source of information in the medical world.