Capillary tissue cylinder, Krogh

A vast amount of work is being done to describe quantitatively the - transport of anabolites and metabolites in the microcirculation of the brain. The classical geometry for the capillaries and tissue has been the Krogh capillary-tissue cylinder. Recent investigations have considered other geometrical configurations to determine if other models derived for multicapillary systems are more descriptive than the single capillary structure used here. 

Table I. Normal Values of Parameters and Variables for the Krogh Capillary—Tissue Cylinder...

Krogh used this solution to express the concentration difference from the capillary (r = R ) to the outside of the tissue cylinder ... 

The basic assumption for all theoretical oxygen tension calculations was introduced by August Krogh. The organs, especially the muscles, are assumed to be composed of numerous, equal tissue cylinders with concentric capillaries. This rough assumption does not cover blood flow differences within the branches of the capillary bed which can be microscopically observed. 

Figure 1.11 Geometry of the Krogh cylinder-type model. The inner cylinder represents the capillary the outer cylinder corresponds to the tissue cylinder. Shaded area example of hypoxic region under conditions of high demand. Rt, tissue cylinder radius Rc, capillary radius z, distance along the capillary. (From McGuire and Secomb, 2001.)...

Krogh tissue cylinder model A cylindrical volume of tissue supplied by a central cylindrical capillary. Myogenic response Vasoconstriction in response to elevated transmural pressure and vasodilation in response to reduced transmural pressure. 

Figure 8.2 Cylindrical geometry of the Krogh-Erlang model of blood-tissue exchange. The upper panel, from Middleman [141], illustrates the assumed parallel arrangement of capillaries with each vessel independently supplying a surrounding cylinder of tissue. A diagram of the model geometry is provided in the lower panel. Figure in upper panel is reprinted with the permission of John Wiley Sons, Inc.

Figure 1. Tissue lump-capillary lump Krogh cylinder model...

Impulse Response for the Krogh Cylinder Model with Plug Flow in the Capillary (Phase 1), Finite Diffusional Resistance Perpendicular to Flow Direction in the Tissue (Phase 2) and No Resistance at the Capillary Wall (Phase Boundary). Equivalent to Case 2. 

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