Perfusion in hamster skin treated with glycerol.

BACKGROUND AND OBJECTIVE The objective of this article is to quantify the effect of hyper-osmotic agent (glycerol) on blood velocity in hamster skin blood vessels measured with a dynamic imaging technique, laser speckle contrast imaging (LSCI). STUDY DESIGN/MATERIALS AND METHODS In this study a dorsal skin-flap window was implanted on the hamster skin. The hyper-osmotic drug, that is, glycerol was delivered to the skin through the open dermal end of the window model. A two-dimensional map of blood flow of skin blood vessels was obtained from the speckle contrast (SC) images. RESULTS Preliminary studies demonstrated that hyper-osmotic agents such as glycerol not only make tissue temporarily transparent, but also reduce blood flow. The blood perfusion was measured every 3 minutes for 36-66 minutes after diffusion of anhydrous glycerol. Blood flow in small capillaries was found to be reduced significantly within 3-9 minutes. Blood flow in larger blood vessels (i.e., all arteries and veins) decreased over time and some veins had significantly reduced blood flow within 36 minutes. At 24 hours, there was a further reduction in capillary blood perfusion whereas larger blood vessels regained flow compared to an hour after initial application of glycerol. CONCLUSION Blood flow velocity and vessel diameter of the micro-vasculatures of hamster skin were reduced by the application of 100% anhydrous glycerol. At 24 hours, capillary perfusion remained depressed.