Capillary diameter in rat heart in situ: Relation to erythrocyte deformability, O2 transport, and transmural O2 gradients

Henquell, L; LaCelle, Paul L.; Honig, Carl R.

doi:10.1016/0026-2862(76)90025-x

Cited by 70 publications

(46 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The diagrammatic representation in Fig. 15 (left) is appropriate in this situation, particularly so because the capillaries are very long (~1 mm) and end-to-end diffusion slow, and long compared to side-to-side intercapillary distances (17-20 µm) and venule-to-arteriole distances (15-50 µm), as shown by Bassingthwaighte et al 4 and Henquell et al 35 Let us consider region II in more detail for the situation following a bolus injection of a highly diffusible tracer into the coronary artery inflow. The average, or steadystate, value of the fractional escape rate, η(t), will always be F/λV for any tracer whose diffusional characteristics put it into regions I, II, or III.…”

Section: Modification Of the Clearance-flow Diagrammentioning

confidence: 99%

Physiology and theory of tracer washout techniques for the estimation of myocardial blood flow: Flow estimation from tracer washout

Bassingthwaighte

1977

Progress in Cardiovascular Diseases

View full text Add to dashboard Cite

Section: Modification Of the Clearance-flow Diagrammentioning

confidence: 99%

Physiology and theory of tracer washout techniques for the estimation of myocardial blood flow: Flow estimation from tracer washout

Bassingthwaighte

1977

Progress in Cardiovascular Diseases

View full text Add to dashboard Cite

“…Cardiac capillaries are, for the most part, long parallel tubes. 7 ' 13 For each field, a single line was drawn perpendicular to the long axis of the capillaries. All measurements of ICD were made on this line.…”

Section: Data Analysis and Statisticsmentioning

confidence: 99%

“…This measurement procedure is illustrated in Martini and Honig 7 and representative photomicrographs appear in Martini and Honig 7 and Henquell and Honig. 13 The method ensures that deviations from a parallel array do not bias our results and that each capillary is considered only once.…”

Section: Data Analysis and Statisticsmentioning

confidence: 99%

See 1 more Smart Citation

Intercapillary distance and capillary reserve in hypertrophied rat hearts beating in situ.

Henquell¹,

Odoroff²,

Honig³

1977

Circulation Research

View full text Add to dashboard Cite

SUMMARY Functional intercapillary distance (ICD) was measured in stop-motion photomicrographs of hypertrophied, normally compensated, well oxygenated rat hearts beating in situ. Left ventricular hypertrophy was produced by salt loading and unilateral nephrectomy. Minimum ICD (when all capillaries are open) also was measured. Ventricular weight increased by 30-40% within 8-9 weeks after nephrectomy. To compare the effect of normal and pathological growth, ICD was also measured in normal rats. In normal animals, minimum ICD and functional ICD increased linearly and proportionately with left ventricular weight. Consequently, the extent to which capillary recruitment could decrease ICD was the same in large and small normal hearts (about 2 fun). In the hypertrophied hearts, capillary recruitment could have maintained ICD within normal limits at rest for several weeks. After 8-9 weeks, however, the capillary reserve in hypertrophy was fully utilized at rest, and mean functional ICD was 1.5-2.0 fitn greater than normal for the age of the animal. An analysis of O 2 transport indicates that anoxic foci would exist throughout the hypertrophied heart and particularly in subendocardium when the capillary reserve is exhausted. The calculated amount of anoxic tissue appears sufficient to account for the focal necrosis and fibrosis observed in hypertrophy and for the development of circulatory failure. WEARN et al.1 -2 were the first to report that myocardial capillary circulation is compromised by the hypertrophy of disease. They concluded that neither the fibers nor the capillaries proliferate, and that the distance between capillaries increases because fiber diameter increases. This view has been challenged by recent studies based on different histological methods which purport to show that capillaries proliferate in pathological hypertrophy. However, it seems likely that capillary growth is not proportional to hypertrophy of the muscle fibers. 9 and V4 the capillaries in left ventricle 9 ' 10 are not perfused at rest. These unperfused capillaries constitute a functional reserve, available for adaptation to stress or disease. Consequently, diffusion distances could be maintained at or near the normal value at rest despite hypertrophy, as long as enough capillaries are available in the reserve. The study to be described was undertaken to: (1) evaluate the capillary reserve in hypertrophied hearts, (2) determine the effect of hypertrophy on the uniformity of diffusion distance, and (3) estimate the effect of altered capillary circulation on O 2 transport. Methods GENERALWe studied female Sprague-Dawley rats. Eight pairs of littermates were fed a standard laboratory diet until they Received June 14, 1976; accepted for publication January 26, 1977. reached 160 g at about 45 days. One member of each pair then was subjected to unilateral nephrectomy. In addition, a 60-mg pellet of deoxycorticosterone was implanted under the skin of the back. One week later, 1% NaCl solution was added to the drinking water. Control rats were n...

show abstract

“…Only two frequency distributions of diameters have been reported, both for myocardium. 1 "- 157 Capillaries taper by about 30% to 40%, 127 so that interpretation of published values of the mean diameter for various tissues is unclear. Diameter and taper may not be the same in long and short capillaries; a relation could strongly influence intracapillary concentration gradients.…”

Section: Capillary Diffusionmentioning

confidence: 99%

Report of the Hypertension Task Force of the National Heart, Lung, and Blood Institute. Current research and recommendations from the Subgroup on Local Hemodynamics.

1980

Hypertension

View full text Add to dashboard Cite

Capillary diameter in rat heart in situ: Relation to erythrocyte deformability, O2 transport, and transmural O2 gradients

Cited by 70 publications

References 21 publications

Physiology and theory of tracer washout techniques for the estimation of myocardial blood flow: Flow estimation from tracer washout

Physiology and theory of tracer washout techniques for the estimation of myocardial blood flow: Flow estimation from tracer washout

Intercapillary distance and capillary reserve in hypertrophied rat hearts beating in situ.

Report of the Hypertension Task Force of the National Heart, Lung, and Blood Institute. Current research and recommendations from the Subgroup on Local Hemodynamics.

Contact Info

Product

Resources

About