Linked Life Data

8395580

Source:http://linkedlifedata.com/resource/pubmed/id/8395580

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1993-9-29
pubmed:abstractText
1. A characteristic plateau pattern was observed in the rate of afferent discharges during ramp-and-hold stretch of spindles isolated from semitendinosus muscles of frogs. The plateau pattern was more frequent in summer frogs (84%) than winter frogs (11%). 2. The plateau pattern consisted of a discharge rate around 120 imp/s at the end of dynamic stretch, followed by second and third steps of plateau rates around 60 and 40 imp/s, respectively. The intervals of impulses in lower steps were approximately n times those of the top step. 3. The plateau pattern was not sensitive to cutting extracapsular myelinated branches or lowering temperature from 23 to 12 degrees C. However, the number of the plateau was reduced in both cases. 4. Application of depolarizing current to the sensory terminal abolished the plateau pattern. In contrast, in spindles that did not show a plateau pattern, hyperpolarizing current induced such a pattern. 5. Calcium channel blockers and protein kinase C inhibitors abolished the plateau pattern. The plateau pattern could be established in quiescent spindles by drugs eliciting Ca2+ entry, raising cytosolic-free Ca2+, and activating protein kinase C. 6. The most striking aspect of the present study is the stability in the discharge rate at each step of the plateau, irrespective of different experimental conditions. This suggests that the spindle sensory terminal possesses a stable intrinsic rhythm generator in excitation, of which maximum frequency is 120 imp/s. The generator seems to be triggered by stretch stimulus and to be regulated by cytoplasmic Ca2+ and protein kinase C.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0022-3077
pubmed:author
pubmed:issnType
Print
pubmed:volume
70
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
275-83
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Plateau pattern of afferent discharge rate from frog muscle spindles.
pubmed:affiliation
Department of Physiology, Nagoya University School of Medicine, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't