Biomaterial Database

Conduction velocity changes along lumbar primary afferent fibers in cats. 1984

A J Rindos, and G E Loeb, and H Levitan

Though peripheral conduction velocity is widely used to characterize afferent fibers according to somatosensory modality, disagreement exists as to whether or not conduction velocity varies along such an axon's length. Therefore, in this experiment, conduction velocities were measured over very short axonal segments (7.5 to 15 mm) within the posterior tibial nerve, sciatic nerve, and L7 dorsal root, using the method of spike-triggered averaging of neurograms recorded from tripolar electrodes. The conduction velocities for several units were also determined using electrical stimulation, so that the accuracy of the two techniques could be compared. For most units, dorsal root and sciatic nerve conduction velocities were not significantly different; however, they were not tightly correlated. Tibial nerve conduction velocity averaged 86% of that within the sciatic nerve. Variations in sciatic nerve conduction velocity within adjacent axonal segments (9 mm in length) rarely exceeded experimental error. It appears that spike-triggered averaging of signals from tripolar electrodes separated 15 mm or more apart is a more accurate method for measuring conduction velocity than electrical stimulation, which was subject to several large errors.

UI	MeSH Term	Description	Entries
D008161	Lumbosacral Region	Region of the back including the LUMBAR VERTEBRAE, SACRUM, and nearby structures.	Lumbar Region,Lumbar Regions,Lumbosacral Regions,Region, Lumbar,Region, Lumbosacral,Regions, Lumbar,Regions, Lumbosacral
D008297	Male		Males
D009412	Nerve Fibers	Slender processes of NEURONS, including the AXONS and their glial envelopes (MYELIN SHEATH). Nerve fibers conduct nerve impulses to and from the CENTRAL NERVOUS SYSTEM.	Cerebellar Mossy Fibers,Mossy Fibers, Cerebellar,Cerebellar Mossy Fiber,Mossy Fiber, Cerebellar,Nerve Fiber
D009431	Neural Conduction	The propagation of the NERVE IMPULSE along the nerve away from the site of an excitation stimulus.	Nerve Conduction,Conduction, Nerve,Conduction, Neural,Conductions, Nerve,Conductions, Neural,Nerve Conductions,Neural Conductions
D010812	Physical Stimulation	Act of eliciting a response from a person or organism through physical contact.	Stimulation, Physical,Physical Stimulations,Stimulations, Physical
D002415	Cats	The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)	Felis catus,Felis domesticus,Domestic Cats,Felis domestica,Felis sylvestris catus,Cat,Cat, Domestic,Cats, Domestic,Domestic Cat
D004558	Electric Stimulation	Use of electric potential or currents to elicit biological responses.	Stimulation, Electric,Electrical Stimulation,Electric Stimulations,Electrical Stimulations,Stimulation, Electrical,Stimulations, Electric,Stimulations, Electrical
D005260	Female		Females
D000344	Afferent Pathways	Nerve structures through which impulses are conducted from a peripheral part toward a nerve center.	Afferent Pathway,Pathway, Afferent,Pathways, Afferent
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia