The objectives of this research proposal are: to study the metabolism of arachidonic acid within brain blood vessels and its component cells from normotensive and hypertensive animals. To examine the extent to which vasoactive molecules modify the metabolism of arachidonic acid in smooth muscle, endothelial cells and in organ culture of small vessels from normotensive and hypertensive animals. To compare arachidonic acid metabolism in cerebral vessels of different sizes. The experiments over the past nine months have focussed on: developing methods for separating cerebral blood vessels into isolates of arterioles and capillaries, as well as methods which maximize the viability of these blood vessels after separation from surrounding parenchyma establishing a cell culture facility for maintaning smooth muscle cells, endothelial cells from large cerebral blood vessels as well as from capillaries and arterioles. Exploring the interaction between platelet products and vascular endothelial and smooth muscle cells in culture. By studying the cerebral blood vessels, its ability to interact with platelet and other circulating factors during health and disease.