TY - JOUR
T1 - Evidence for stretch-induced resistance increase of proximal coronary microcirculation
AU - Cornelissen, A. J.
AU - Spaan, J. A.
AU - Dankelman, J.
AU - Chan, C. C.
AU - Yin, F. C.
PY - 2001
Y1 - 2001
N2 - We investigated the influence of stretch on regional hemodynamic parameters of the septal circulation. We used a similar experimental setup and mathematical model, as described previously (14). Five ventricular septa were isolated from anesthetized dogs, sutured to a biaxial stretching apparatus, and perfused with an oxygenated perfluorochemical emulsion at maximal vasodilation. Under unloaded and biaxially stretched conditions, flow and septal thickness (to index vascular volume) were measured continuously. Pressure was varied sinusoidally at 30, 50, and 70 mmHg with amplitude of 7.5 mmHg over frequencies ranging between 0.015 and 7 Hz. Admittance (flow/pressure) and capacitance (thickness/pressure) transfer functions were calculated and interpreted in terms of a two-compartmental model with volume-dependent resistances. Parameter estimation showed that the proximal resistance and compliance were unaffected, whereas the resistance of the proximal part of the microcirculation, including the small arterioles, increased with stretch. The effect of stretch on the distal resistance and capacitance, however, could not be determined unequivocally
AB - We investigated the influence of stretch on regional hemodynamic parameters of the septal circulation. We used a similar experimental setup and mathematical model, as described previously (14). Five ventricular septa were isolated from anesthetized dogs, sutured to a biaxial stretching apparatus, and perfused with an oxygenated perfluorochemical emulsion at maximal vasodilation. Under unloaded and biaxially stretched conditions, flow and septal thickness (to index vascular volume) were measured continuously. Pressure was varied sinusoidally at 30, 50, and 70 mmHg with amplitude of 7.5 mmHg over frequencies ranging between 0.015 and 7 Hz. Admittance (flow/pressure) and capacitance (thickness/pressure) transfer functions were calculated and interpreted in terms of a two-compartmental model with volume-dependent resistances. Parameter estimation showed that the proximal resistance and compliance were unaffected, whereas the resistance of the proximal part of the microcirculation, including the small arterioles, increased with stretch. The effect of stretch on the distal resistance and capacitance, however, could not be determined unequivocally
M3 - Article
C2 - 11709438
SN - 0363-6135
VL - 281
SP - H2687-H2696
JO - American journal of physiology. Heart and circulatory physiology
JF - American journal of physiology. Heart and circulatory physiology
IS - 6
ER -