ISSN:
1432-1106
Keywords:
Trigeminal nerve
;
Primary afferent fiber
;
Trigeminal spinal nucleus
;
PAD
;
Intra-axonal record
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Summary Intra-axonal recordings were made from trigeminal primary afferent fibers in the trigeminal spinal nuclei oralis and caudalis of cats. Primary afferent depolarization (PAD) was evoked in these afferents by stimulation of the trigeminal peripheral sensory branches (the frontal, infraorbital and lingual nerves), the cerebral cortex and the trigeminal spinal nucleus caudalis. The properties of the PAD, including the threshold, latency, receptive field (sensory branches effective for PAD induction) and frequency-following capacity, were studied with the following results: 1. Stimulation of all the peripheral branches tested as well as the cerebral cortex could evoke PAD in the same single fiber. The latency of the PAD evoked by stimulation of the nerve in which the fiber being recorded from was included was generally shorter than that evoked by other branches. The PAD evoked by peripheral nerve stimulation was assumed to be disynaptic in some cases. 2. The peripherally evoked PAD was chiefly attributable to low threshold afferents in the stimulated sensory branches of the trigeminal nerve. 3. The peripherally evoked PAD could follow stimulation at up to 30/sec, though the amplitude was reduced. 4. Stimulation of the nucleus caudalis could evoke PAD with disynaptic latency in the majority of the fibers terminating in the same nucleus, whereas it evoked PAD with mainly polysynaptic latency in the fibers terminating in the nucleus oralis. The results are discussed in relation to the neuronal circuitry responsible for induction of the trigeminal PAD.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00236874
Permalink
