New monochromatic synchrotron radiation microangiography system to measure intra and extracerebral arteriole changes in the rat.
BACKGROUND AND PURPOSE: Using a newly developed angiography system, which consists of monochromatic synchrotron radiation (MSR) as an X-ray source with a high-resolution camera system, we aimed at obtaining simultaneous in vivo three-dimensional (3D) cerebral vessel images and making observations of the intra- and extracerebral arterioles in rats during reperfusion after transient forebrain ischemia. METHODS: The detector features a 7μm equivalent pixel size projected onto the input area and an input field size of 7.0 mm x 7.0 mm. The changes in the cerebral microvessels were observed continuously before and for 30 min after transient cerebral ischemia with the MSR angiography system. RESULTS: Micro 3D rotational angiography provided good visibility of the rat intra- and extracerebral arterioles under basal conditions. The diameters of the middle cerebral artery and striate artery significantly increased one min after reperfusion, while the pial arteriole diameter significantly decreased. Thereafter, all of the three-type vessels significantly increased at 10 min after reperfusion. CONCLUSION: We herein describe and discuss the use of an in vivo experimental model in which changes in transient cerebral ischemia in the rat cerebral microcirculation were clearly depicted with an MSR angiography system. These findings show that an assessment of the cerebral regulation system can thus be performed easily and quantitatively using this method.