Microvascular behavior and effects of sonazoid microbubbles in the cremaster muscle of rats after local administration.
OBJECTIVE
The purpose of this study was to observe Sonazoid perfluorobutane microbubbles (GE Healthcare, Amersham, Buckinghamshire, England) in and their effects on the cremaster capillary microcirculation of rats.


METHODS
Sonazoid (0.3 x 10(9) microbubbles in 0.5 mL) was observed by intravital microscopy in the cremaster muscle after retrograde administration into the femoral artery of 6 animals. Microbubble and microvessel diameters and blood flow velocities and the overall mean and SD of the 1-minute volume flow through the microscopic field were calculated from the 2 to 4 capillaries observed in the field of each animal. Fluorescein isothiocyanate-dextran leakage was used to assess extravasation after microbubble passage.


RESULTS
seconds, respectively, before they were released and capillary flow normalized. No microbubble size changes, damming, or coalescence of bubbles and no changes in microvessel diameter or microvascular blood flow velocities, volume flow, or perfusion heterogeneity occurred during or after the passage of the Sonazoid suspension or the vehicle. No fluorescein isothiocyanate-dextran leakage was observed.


CONCLUSIONS
The passage of Sonazoid bubbles at concentrations higher than those expected after intravenous administration of the Sonazoid did not durably impair microvascular perfusion, structural integrity, or macromolecular retention in the rat cremaster muscle. The duration of discrete capillary obstructions was short and in all cases comparable with that of naturally occurring leukocyte plugging.
Braide
Magnus
M
Department of Anatomy and Cell Biology, University of Göteborg, Sweden.
Rasmussen
Henrik
H
Albrektsson
Ann
A
Bagge
Ulf
U
D000818:Animals; D005466:Fluorocarbons / Q000494:pharmacology*; D008297:Male; D045423:Microbubbles; D009130:Muscle, Smooth / Q000098:blood supply* / Q000187:drug effects*; D051381:Rats; D013737:Testis
D005466:Fluorocarbons; C108042:perfluorobutane