Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5 Pt 2
pubmed:dateCreated
1991-12-23
pubmed:abstractText
It is known that a substantial amount of capillary tortuosity is found in shortened muscles. However, the increased capillary length and surface area contributed by tortuosity and branching are seldom taken into account when capillarity is estimated and/or blood-tissue exchange is modeled in muscles. In this paper, we sought morphometric estimates of capillarity in transverse sections that incorporated data on capillary geometry. We derived equations to estimate capillary perimeter per fiber perimeter (i.e., capillary-to-fiber perimeter ratio) in transverse sections. We show how capillary-to-fiber perimeter ratio is related to capillary surface per fiber surface, i.e., to the amount of capillary surface available for exchange per muscle fiber surface area, and how it can be obtained by morphometry. Because capillary tortuosity and fiber perimeter are both a function of sarcomere length, the degree of extension or shortening of muscle samples obviously needs to be taken into account when capillary-to-fiber perimeter ratio is compared between muscles and/or samples. Using data currently available on capillary length and diameter with fiber shortening and extension, we show that it is a feature of capillary-to-fiber perimeter ratio to change relatively little with sarcomere length. As sarcomere length decreases from 2.80 to 1.58 microns in perfusion-fixed hindlimb muscles of rats, capillary and fiber perimeters in transverse sections increase substantially, whereas the ratio between the two variables, capillary-to-fiber perimeter ratio, changes only less than or equal to 10-15%.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
261
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
H1617-25
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Muscle capillary-to-fiber perimeter ratio: morphometry.
pubmed:affiliation
Department of Medicine, University of California, San Diego, La Jolla 92093-0623.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't