Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1988-2-8
pubmed:abstractText
Mechanical characteristics and electrical activity were studied in the extraocular muscles of the catfish, Ictalurus punctatus. The contractile properties were determined by stimulation of the individual muscle nerve branches to lateral and medial rectii and the superior and inferior oblique muscles. The speed of contraction was higher than in most other fish muscle, with a twitch contraction time of about 12 ms and a tetanus fusion frequency of 150-170 Hz in all four eye muscles. The fatigue resistance was also high. These properties were the same in fully innervated and partially innervated muscle, largely irrespective of what part of the muscle that was activated. Although different fibre types are known to exist in fish extraocular muscle, it was not possible to obtain functional separation of the mechanical force profile even in the lateral rectus with two distinct motoneuronal innervations. We suggest that polyneuronal innervation of the muscle fibres produces the mechanical responses. Since EMG activity during spontaneous eye movements was similar in the global and the orbital parts of the muscle, all types of fibres in fish extraocular muscle are probably recruited for all types of eye movements.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0001-6772
pubmed:author
pubmed:issnType
Print
pubmed:volume
131
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
361-9
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
Motoneuronal innervation and mechanical properties of extraocular muscles in the catfish, (Ictalurus punctatus).
pubmed:affiliation
Department of Ophthalmology, Karolinska Institute, Huddinge Hospital, Stockholm, Sweden.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't