Golgi tendon organ

from Wikipedia, the free encyclopedia
Golgi tendon organ
from Gray's Anatomy, 1918

The Golgi tendon organ present in all vertebrates , named after Camillo Golgi , is a sense organ of deep sensitivity . It is a kind of nerve network that is used to measure and regulate muscle tension . It is located at the transition between muscle and tendon and, together with the muscle spindles, is responsible for proprioception of the muscles.

The Golgi tendon organs use class Ib nerve fibers to transmit information to the central nervous system about the state of tension in the respective muscles. Skin and joint afferents also play a role, as do Ia and II afferents of the muscle spindles. The effect of this multimodal signal is mainly inhibitory on the motor neuron of one's own muscle (autogenic inhibition). In addition, the antagonist is activated via excitatory interneurons .

construction

The Golgi tendon organ consists of a connective tissue capsule (perineural capsule) traversed by tendon fibers, which surrounds the branched end of an afferent nerve fiber of type Ib. The tendon fibers run through the sensitive endings of the nerve.

function

An increase in muscle tension causes the tendon to tighten. As a result, the nerve fiber ends that run through the tendon fibers are stretched and an action potential is triggered through the mechanosensitive ion channels . This is transmitted via Ib nerve fibers to the spinal cord, where it is transmitted to several interneurons in the anterior horn of the spinal cord. These interneurons inhibit the activity of the muscle's motor neuron (autogenic inhibition) and increase that of the antagonists. In addition, the signals are passed on to the primary somatosensory cortex via the lemniscale system .

Inverse stretch reflex (autogenic inhibition)

The inverse stretch reflex is a self-reflex . By activating the Golgi tendon organ, u. a. activates an inhibitory interneuron in the spinal cord, which has an inhibitory effect on the α-motor neuron and thus on muscle tension. The aim of this reflex is to keep the muscle tension in an optimal range. In extreme situations, it protects the muscle from overload.

See also

Individual evidence

  1. ↑ Antje Hüter-Becker, among other things: biomechanics, kinetics, performance physiology, training theory. Thieme Verlag, 2005, ISBN 3-13-136861-6 , p. 104, (online)
  2. ↑ S. Silbernagl, A. Despopoulos: Pocket Atlas of Physiology. 7th edition. Thieme 2007, ISBN 978-3-13-567707-1 , (online)
  3. ^ Mark F. Bear: Neuroscience . Ed .: Andreas K. Engel. 3. Edition. Springer Verlag, ISBN 978-3-8274-2028-2 .

literature

  • Mark F. Bear, Barry W. Connors, Michael A. Paradiso: Neurosciences . Translated from the English by Andreas Held, Catherine Hornung a. a. 3. Edition. Spektrum Akademischer Verlag, Heidelberg 2009, ISBN 978-3-8274-2028-2 , pp. 492-493.
  • Renate Lüllmann-Rauch: pocket textbook histology. 2nd Edition. Georg Thieme Verlag, Stuttgart 2006, ISBN 3-13-129242-3 , p. 548.
  • RF Schmidt, F. Lang, M. Heckmann: Human physiology - with pathophysiology . 31st edition. Springer Medizin Verlag, Heidelberg 2010, ISBN 978-3-642-01650-9 .