Linked Life Data

3612223

Source:http://linkedlifedata.com/resource/pubmed/id/3612223

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1987-9-14
pubmed:abstractText
1. The electrophysiological properties of alpha-motoneurons in old cats (14-15 yr) were compared with those of adult cats (1-3 yr). These properties were measured utilizing intracellular recording and stimulating techniques. 2. Unaltered in the old cat motoneurons were the membrane potential, action potential amplitude, and slopes of the initial segment (IS) and soma dendritic (SD) spikes, as well as the duration and amplitude of the action potential's afterhyperpolarization. 3. In contrast, the following changes in the electrophysiological properties of lumbar motoneurons were found in the old cats: a decrease in axonal conduction velocity, a shortening of the IS-SD delay, an increase in input resistance, and a decrease in rheobase. 4. In spite of these considerable changes in motoneuron properties in the old cat, normal correlations between different electrophysiological properties were maintained. The following key relationships, among others, were the same in adult and old cat motoneurons: membrane potential polarization versus action potential amplitude, duration of the afterhyperpolarization versus motor axon conduction velocity, and rheobase versus input conductance. 5. A review of the existing literature reveals that neither chronic spinal cord section nor deafferentation (13, 21) in adult animals produce the changes observed in old cats. Thus we consider it unlikely that a loss of synaptic contacts was responsible for the modifications in electrophysiological properties observed in old cat motoneurons. 6. We conclude that during old age there are significant changes in the soma-dendritic portion of cat motoneurons, as indicated by the modifications found in input resistance, rheobase, and IS-SD delay, as well as significant changes in their axons, as indicated by a decrease in conduction velocity.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0022-3077
pubmed:author
pubmed:issnType
Print
pubmed:volume
58
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
180-94
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
Basic electrophysiological properties of spinal cord motoneurons during old age in the cat.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't