Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1993 May 15;81(10):2636-43.

Characterization of ultrasound-potentiated fibrinolysis in vitro

Affiliations
  • PMID: 8490172
Free article

Characterization of ultrasound-potentiated fibrinolysis in vitro

A Blinc et al. Blood. .
Free article

Abstract

We have characterized the effects of ultrasound on fibrinolysis in vitro to investigate the mechanism of ultrasonic potentiation of fibrinolysis and to identify potentially useful ultrasound parameters for therapeutic application. Radiolabeled clots in thin walled tubes were exposed to ultrasound fields in a water bath at 37 degrees C, and lysis was measured by solubilization of radiolabel. Ultrasound accelerated lysis of plasma, whole blood, and purified fibrin clots mediated by recombinant tissue-type plasminogen activator (rt-PA), urokinase, or streptokinase, but ultrasound by itself caused no clot solubilization. The degree of ultrasonic potentiation was dependent on plasminogen activator concentration, increasing from 2.2-fold at a streptokinase concentration of 75 U/mL to 5.5-fold at 250 U/mL in a 1 MHz ultrasound field at 4 W/cm2. Ultrasound exposure resulted in heating due to absorption by the plastic tube, but the temperature increase was insufficient to account for the increase in clot lysis rate, indicating that the primary effect was nonthermal. Ultrasound did not accelerate hydrolysis of a peptide substrate by rt-PA and did not alter the rate of plasmic degradation of fibrinogen, indicating that the augmentation of enzymatic fibrinolysis required the presence of a fibrin gel. The acceleration of fibrinolysis by ultrasound was greater at higher intensities and duty cycles and was maximum at frequencies between 1 and 2.2 MHz, but decreased at 3.4 MHz. These findings suggest that ultrasound accelerates enzymatic fibrinolysis by increasing transport of reactants through a cavitation-related mechanism.

PubMed Disclaimer

Similar articles

Cited by

Publication types

LinkOut - more resources