Increased sciatic nerve blood flow in diabetic rats: assessment by
'molecular' versus particulate microspheres.
Chang, Kathy, Yasuo Ido, Wanda Lejeune, Joseph R. Williamson, and
Ronald G. Tilton[acute]a.
Department of Pathology, Washington University School of Medicine,
660 South Euclid Avenue, St. Louis, Missouri 63110, [acute]a
Department of Cellular Biology, Texas Biotechnology Corporation, 7000
Fannin, Houston, Texas 77030 USA
APStracts 4:0067E, 1997.
Sciatic nerve blood flow in diabetic rats is typically increased or
unchanged when assessed by the reference sample microsphere method in
our laboratory; in contrast, blood flow is generally reported to be
decreased 50 % when assessed with laser Doppler flowmetry or hydrogen
clearance polarography. To address concerns that increased blood flow
observed with microspheres might be anomalous because of their
particulate nature and/or because insufficient numbers of
microspheres are captured in the nerve, a plasma soluble 'molecular
microsphere' (3H-desmethylimipramine, mol wt = 276) and 11.3 m 153Gd
-microspheres were injected sequentially to assess blood flow in rats
with streptozotocin diabetes of 2 to 4 weeks duration. Nerve blood
flows in diabetic rats were increased 1.5 to 2 fold (vs control rats)
with both tracers; these increases were prevented by tolrestat, an
inhibitor of aldose reductase. These observations indicate that blood
flow in sciatic nerve (like that in retina and kidney) is increased
early after the onset of diabetes and is: 1) demonstrable with a
plasma soluble tracer as well as with particulate microspheres, and
2) linked to increased metabolism of glucose via the sorbitol
pathway.
Received 31 October 1996; accepted in final form 5 March 1997.
APS Manuscript Number E545-6.
Article publication pending Am. J. Physiol. (Endocrinol. Metab.).
ISSN 1080-4757 Copyright 1997 The American Physiological Society.
Published in APStracts on 21 March 1997