Interneurones of the supratrigeminal area mediating reflex inhibition of trigeminal and facial motorneurones in the rat
| Autor: | J.D. van Willigen, P.J.W. Jüch, R.F. Minkels |
|---|---|
| Rok vydání: | 1995 |
| Předmět: |
Male
Periodontium Reflex Stretch Facial motor nucleus Mandibular Nerve Action Potentials Sensory system Stimulus (physiology) Inferior alveolar nerve Inhibitory postsynaptic potential Trigeminal Nuclei Postsynaptic potential Interneurons Neck Muscles Pons medicine Animals Neurons Afferent General Dentistry Muscle Spindles Motor Neurons Chemistry Masseter Muscle Neural Inhibition Cell Biology General Medicine Anatomy Electric Stimulation Rats body regions Facial Nerve Trigeminal motor nucleus medicine.anatomical_structure nervous system Otorhinolaryngology Excitatory postsynaptic potential Mastication Microelectrodes |
| Zdroj: | Archives of oral biology. 40(4) |
| ISSN: | 0003-9969 |
| Popis: | Whether sensory information from the inferior alveolar nerve is mediated by different types of interneurones in the supratrigeminal area (Su5) and whether different types of these interneurones have different inhibitory actions on jaw-closing motor neurones of the trigeminal motor nucleus was investigated. The intracellular responses of periodontal afferents in the mesencephalic trigeminal nucleus, Su5 interneurones and jaw-closing motor neurones were studied in response to graded, single-shock stimulation of the ipsilateral inferior alveolar nerve. It was found that the inhibitory action of afferent inflow from the inferior alveolar nerve to jaw-closing motor neurones is possibly mediated by two types of Su5 interneurones (T-I and T-II). These Su5 neurones were discriminated on the basis of their firing characteristics. The findings also indicated that: (1) T-I neurones are responsible for short-latency, low-threshold inhibitory postsynaptic potentials (IPSPs) observed in the trigeminal motor nucleus neurones; (2) T-II interneurones mainly contribute to the amplitude of these IPSPs at higher stimulus strengths; (3) the late part of plateau IPSPs in the jaw-closing motor neurones is induced by a characteristic firing of T-II neurones. It was also shown that afferent inflow from the inferior alveolar nerve, probably mediated by collaterals of T-I and T-II interneurones, also evokes IPSPs in neurones of the intermediate subnucleus of the facial motor nucleus. The characteristics of these IPSPs resemble those of the IPSPs recorded in the jaw-closing motor neurones. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect