神経系

Neurons and Glia The neuron doctrine The Golgi Stain Cajal’s contribution CAMILLO GOLGI 1843-1926 Italy Pavia University SANTIAGO RAMON Y CAJAL 1852-1934 Spain Madrid University 1906 Nobel Laureate in Medicine in recognition of their work on the structure of the nervous system

Histology The microscopic study of the structure of tissue. Nissl stain: Introduced by German neurologist Franz Nissl in the late 19th century. A class of basic die stain the nuclei of all cells and also stain clumps of material surrounding the nuclei of neurons.

The Golgi Stain Italian histologist Camillo Golgi discovered that by soaking brain tissue in a silver chromate solution, Golgi stain, a small percentage neurons became darkly colored in their entirety.

Drawing by Camillo Golgi of a hippocampus stained with the silver nitrate method Drawing of a Purkinje cell in the cerebellum cortex done by Santiago Ramón y Cajal, clearly demonstrating the power of Golgi's staining method to reveal fine detail.

Glial cells Glial cells are thought to contribute to brain function mainly by insulating, supporting, and nourishing neighboring neurons. There are at least three types of glia; astrocytes, microglia, and oligodendrocytes.

Important roles of glial cells Greg Miller, Science 308; 778-781, 2005

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Microglia It was R. Cajal's student, Pio del Rio-Hortega, who coined the term microglia around 1920. He conducted the first systematic studies on this cell type. The cells had been previously described by F. Nissl and F. Robertson but Rio-Hortega is rightly considered the "father" of the microglia. Many of his observations are still valid. Resting microglia show characteristic elongated, almost bipolar cell bodies with spine-like processes that often branch perpendicularly.