Muscle blood flow in the cat: comparison of the microdialysis
ethanol technique to direct measurement.
Hickner, Robert C., Ulf Ekelund, Stefan Mellander, Urban Ungerstedt,
and Jan Henriksson.
Department of Physiology and Pharmacology, Division of Physiology
III and Pharmacology, The Karolinska Institute, S-114 86 Stockholm
and the Department of Physiology and Biophysics, University of Lund,
S-223 62, Lund, Sweden
APStracts 2:0137A, 1995.
A quantitative validation of the microdialysis ethanol technique was
performed in cat gastrocnemius muscle. Six to eight microdialysis
probes were inserted into the isolated muscle preparation and
perfused (0.5 - 10.0 Nl min-1) with Krebs-Henseleit buffer containing
between 5 and 1000 mmol l-1 ethanol. Skeletal muscle blood flow was
held constant in the range of 4-99 ml 100g-1 min-1 by a servo
-controlled roller pump and was determined using the microdialysis
ethanol technique as well as by timed collection of venous outflow.
The ethanol outflow/inflow ratio ([ethanol]collected
dialysate/[ethanol]infused perfusion medium) decreased in a non
-linear fashion when microdialysis perfusion flow rates of 0.5 and 1.0
Nl min-1 were employed. However, a linear decrease was found between
4 and approximately 45 ml 100g-1 min-1 (r=-0.92--0.99). The lower the
outflow/inflow ratio was at 4 ml 100g-1 min-1 (i.e. due to a low
probe perfusion flow rate or a large dialysis membrane), the greater
was the sensitivity of the method. It is concluded that this non
-radioactive technique provides a simple and valid method for
determining nutritive blood flow in skeletal muscle.
Received 13 June 1994; accepted in final form 10 March 1995.
APS Manuscript Number A578-4.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 10 April 1995.