Cerebral circulation revisited: an historical essay.

Three centuries of investigations relevant to cerebral circulation, from the discoveries of circulation by Harvey (1628) and Willis (1664) to the 2-deoxyglucose methods of Sokoloff (1977), have been surveyed. Perspective is provided from discussion of such developments as: the discovery of oxygen and its role in combustion, respiration and cellular metabolism; recognition of the blood-brain barrier especially as selective exchange transport systems; introduction of the concept of metabolism and elucidation of details of glycolysis and oxidative phosphorylation; the discovery of neurotransmitters and an understanding of the ionic bases for conduction and neural activity; and introduction of modern techniques for studying cerebral circulation and metabolism, specifically, the Kety-Schmidt N2O method and the Sokoloff [14C]deoxyglucose autoradiographic method for regional and local applications, with subsequent adaptation to PET studies in situ.