Detailed Animation on Tendon Reflex скачать в хорошем качестве

Detailed Animation on Tendon Reflex

A tendon reflex is initiated by a substantial amount of tension in a muscle tendon, and results in the reflex relaxation of the skeletal muscle attached to that tendon. It is less sensitive than the stretch reflex, but produces an opposite effect. 1. Golgi tendon organ The reflex begins when sensory receptors known as Golgi tendon organs are activated. Golgi tendon organs are located within a tendon, at its junction with a muscle, and are activated in response to increased tension, such as when a tendon is tapped with a tendon hammer for example. 2. Sensory neuron This fires an action potential along a somatic sensory neuron, which travels via the dorsal root of a spinal nerve into the spinal cord. 3. Inhibitory interneuron Here, the sensory neuron synapses with an inhibitory interneuron, which in turn synapses ipsilaterally with a motor neuron in the anterior gray horn of the spinal cord. 4. Motor neurons The interneuron releases an inhibitory neurotransmitter that inhibits the motor neuron, making it less excitable and reducing the likelihood of an action potential being generated. 5. Skeletal muscle This leads to relaxation of the skeletal muscles attached to the stretched muscle tendon (in this case the extensor muscles of the knee), thereby reducing tension in the tendon and protecting it from damage. In addition, the sensory neuron also synapses with an excitatory interneuron, which in turn synapses ipsilaterally with a motor neuron that controls the antagonistic muscles (in this case the flexors of the knee). This leads to contraction of these muscles, which causes the simultaneous relaxation of the muscle connected to the tendon under tension. The contraction of one muscle that results in the relaxation of its antagonist is known as reciprocal innervation.