[Effect of echo-contrast agent on rat vascular smooth muscle cell proliferation during ultrasound exposure].

Objective: To investigate the effect of echo-contrast agent on rat vascular smooth muscle cell (VSMC) proliferation in the presence of ultrasound exposure.

Methods: The VSMCs of rats were cultured in 6-well plates with or without the echo-contrast agent and stained with trypan blue at 3, 24, and 48 h respectively after ultrasound exposure for 1 min at 2 MHz, 0.25 mechanical index (MI). At each time point as indicated after the exposure, the cells in parallel wells were trypsinized for cell counting using Coulter counter.

Results: No cytotoxicity was found in trypan blue staining. Compared with the control cells, the proliferation of VSMCs was inhibited by echo-contrast agent and adjunctive ultrasound within 24 h, but another 24 h later, the effect failed to be observed.

Conclusions: The proliferation of VSMC was inhibited by with low mechanical index cavitation activity of contrast agents.