Linked Life Data

11549745

Source:http://linkedlifedata.com/resource/pubmed/id/11549745

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
18
pubmed:dateCreated
2001-9-10
pubmed:abstractText
The Aplysia multifunctional feeding central pattern generator (CPG) produces at least two types of motor programs, ingestion and egestion, that involve two sets of radula movements, protraction-retraction and opening-closing movements. In ingestion, the radula closes during retraction to pull food in, whereas in egestion, the radula closes during protraction to push inedible objects out. Thus, radula closure shifts the phase in which it occurs with respect to protraction-retraction in the two programs. To identify the central switching mechanisms, we compared activity of CPG neurons during the two types of motor programs elicited by a higher-order interneuron, cerebral-buccal interneuron-2 (CBI-2). Although CPG elements (B63, B34, and B64) that mediate the protraction-retraction sequence are active in both programs, two other CPG elements, B20 and B4/5, are preferentially active in egestive programs and play a major role in mediating CBI-2-elicited egestive programs. Both B20 and B4/5 control the phasing of radula closure motoneurons (B8 and B16) to ensure that, in egestive programs, these motoneurons fire and produce radula-closing movements only during protraction. Elsewhere, another higher-order interneuron, CBI-3, was shown to convert CBI-2-elicited egestion to ingestion. We show that CBI-3 switches the programs by suppressing the activity of B20 and B4/5. CBI-3, active only during protraction, accomplishes this through fast inhibition of B20 during protraction and slow inhibition of B4/5 during retraction. The slow inhibition is mimicked and occluded by APGWamide, a neuropeptide contained in CBI-3. Thus, fast conventional and slow peptidergic transmissions originating from the same interneuron act in concert to meet specific temporal requirements in pattern switching.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
1529-2401
pubmed:author
pubmed:issnType
Electronic
pubmed:day
15
pubmed:volume
21
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
7349-62
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Neural mechanisms of motor program switching in Aplysia.
pubmed:affiliation
Department of Physiology and Biophysics, Mount Sinai School of Medicine, New York, New York 10029-6574, USA. jjing@inka.mssm.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.