Linked Life Data

9224832

Source:http://linkedlifedata.com/resource/pubmed/id/9224832

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1997-9-12
pubmed:abstractText
Non-monosynaptic group I and group II excitation of human lower limb motoneurones was investigated. Changes in the firing probability of individual voluntarily activated motor units belonging to various muscles (soleus, gastrocnemius medialis, tibialis anterior, peroneus brevis, quadriceps and biceps femoris) were investigated after stimulation of various nerves (posterior tibial, common peroneal and femoral nerves) with weak (0.4-0.6x motor threshold) electrical stimuli. In all investigated motor nuclei, stimulation of the "homonymous" nerve evoked a peak of increased firing probability with a latency that was 3-7 ms longer than the monosynaptic Ia latency. The more caudal the motor nucleus explored, the greater the central delay. This strongly suggests a transmission through neurones located above the lumbar enlargement. If one excepts the sural-induced excitation of peroneus brevis units, which seems to be mediated through a particular pathway, the main peripheral input to neurones mediating non-monosynaptic excitation evoked by these weak stimuli is group I in origin. The pattern of distribution of non-monosynaptic group I excitation was very diffuse, since stimulation of each nerve was able to evoke excitation in all investigated nuclei. In most cases, non-monosynaptic excitation evoked in a given motor unit by stimulation of one nerve was depressed on combined stimulation of two nerves, and evidence is presented that this lateral inhibition is exerted at a premotoneuronal level. By contrast, there was no evidence that increasing the afferent input in a given pathway evokes an "autogenetic" inhibition in this pathway. The negative correlation found between non-monosynaptic group I-induced and late group II-induced facilitation of the quadriceps H-reflex when using high stimulus intensities applied on the common peroneal nerve suggests that these two effects could be mediated through common interneurones.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0014-4819
pubmed:author
pubmed:issnType
Print
pubmed:volume
115
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
35-46
pubmed:dateRevised
2009-11-11
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Further evidence for non-monosynaptic group I excitation of motoneurones in the human lower limb.
pubmed:affiliation
UMR CNRS 5549 (CERCO), Faculté de Médecine, Toulouse, France.
pubmed:publicationType
Journal Article, Clinical Trial, Research Support, Non-U.S. Gov't