Quantitative histochemistry of the cerebral cortex.

For some years in this laboratory the principles and methods of quantitative histochemistry introduced by Linderstr#{216}m-Lang and loiter (7, 10) have been used for studies on the chemical pathology of the nervous system. A particular effort has been made to describe the biochemical architecture of rat and human cerebral cortex, primarily because of its intrinsic neurological importance and the implications of its function for behavior. In addition, the laminated architecture of the cortex makes it a subdivision of the nervous system suitable for study by alternate section sampling and microanalysis of the Linderstr#{216}mLang type. Whether analyzed in terms of nerve cell bodies, or of fibrillar and protoplasmic plexuses, or of myelinated segments of intracortical axones, or even of blood vessels and glial elements, the isocortex presents a characteristic stratification of its anatomical components (1, 2, 13). Therefore, biochemical analyses at successive intracortical levels should not only provide quantitative information on cortical chemoarchitectonics, but also provide the basis for correlations between any differential distributions of chemical constituents and the selective non-uniformity of histological components. For carrying out such studies and testing the foregoing hypothesis, use has been made of an experimental design modified from that of Linderstr#{216}m-Lang and Mogensen (12), and described in detail previously (17). From a fresh frozen block of cortex, a cylinder 2 mm in diameter is punched out, and from it horizontal, 20 u thick microtome sections are cut at 12#{176}C from pia to white matter. These are used in con-