AIMTo isolate and purify the brain microvessels without intact neural cells used for cloning specific gene at the blood-brain-barrier.

METHODSMagnetic beads ranging from 200-500 nm were synthesized and infused into cerebral spheres through carotid arteries. The brain tissues were dissected by mechanic and enzymatic methods, and sieved to discharge tissues and large blood vessels. The brain microvessels labelled by magnetic beads were sorted in magnetic fields, and identified by morphology, molecular biology and biologic activity.

RESULTSScanning electric micrograph of the obtained brain microvessels showed the vessels grossly free of adjoining neural cells except an occasional nerve ending. RT-PCR products of microtube-associated protein 2a, glutamine synthetase and CD31 from brain tissue had positive lanes, but only CD31 had positive lanes from isolated microvessels. The endothelial cells from isolated microvessels had more fluorescence than that from cultured endothelial cells.

CONCLUSIONHighly purified microvessels without intact neural cells can be obtained by this method.