Direct effects of Rho-kinase inhibitor on pial microvessels in rabbits

作者：Kotoda Masakazu^*; Ishiyama Tadahiko; Shintani Noriyuki; Matsukawa Takashi

来源：Journal of Anesthesia, 2015, 29(2): 186-190.

DOI：10.1007/s00540-014-1903-x

• Rho-kinase
• Y-27632
• Pial microvessels

Rho-kinase inhibitor is widely used for prevention of cerebral vascular spasm. However, the cerebral pial vascular action of Rho-kinase inhibitor has not been investigated. We therefore evaluated the direct effects of Y-27632, a Rho-kinase inhibitor, on pial microvessels.
Experiments were performed on anesthetized rabbits. A closed cranial window was used to visualize the pial microcirculation. After baseline hemodynamic and pial vascular measurements, the cranial window was superfused with four increasing concentrations of Y-27632 (10(-9), 10(-7), 10(-6), 10(-5) mol l(-1); n = 7) dissolved in artificial cerebrospinal fluid for 7 min each. We measured the diameters of pial vessels, mean arterial pressure (MAP), heart rate (HR), and rectal temperature at 7 min after application of each Y-27632 concentration.
MAP, HR, rectal temperature, arterial pH, PaCO2, PaO2, and plasma Na+, K+ and glucose concentrations did not change significantly during the experimental period. Y-27632 at 10(-9) to 10(-7) mol l(-1) did not produce any significant change in pial arterioles. Topical application of Y-27632 at 10(-6) and 10(-5) mol l(-1) produced pial large (8.4 +/- A 5.7 and 19.8 +/- A 12.7 %) and small (10.1 +/- A 8.5 and 18.1 +/- A 12.3 %) arterioles dilation. However, Y-27632 did not produce any change in pial large and small venules.
We evaluated the direct effects of Y-27632 on pial microvessels. Y-27632 dilates only pial arterioles in a concentration-dependent manner, and most at a concentration of 10(-5) mol l(-1). Y-27632 is a potent cerebral pial arteriolar dilator but is not a venular dilator.

• 出版日期2015-4