Camillo Golgi

The Italian physician whose 'black reaction' stain made individual neurons visible for the first time — and who, ironically, used it to defend the wrong theory.

Camillo Golgi (1843–1926) was born in Corteno, a village in Lombardy now renamed Corteno Golgi in his honour. He trained in medicine at the University of Pavia, where he would spend most of his career.

The kitchen laboratory

In 1872 he took a post as chief physician at a hospital for the chronically ill in Abbiategrasso. With no proper laboratory, he set up a microscope in the hospital kitchen and worked at night. There, in 1873, he discovered the black reaction (reazione nera): tissue hardened in potassium dichromate and soaked in silver nitrate showed a few neurons stained black in their entirety. Golgi used it to describe nerve cells in the cerebellum, olfactory bulb and spinal cord, and identified two types of neurons — those with long axons (now called Golgi type I) and those with short axons that stay local (Golgi type II).

The Golgi apparatus and tendon organ

Golgi's name is attached to several discoveries. In 1898 he described an internal network in nerve cells — now known as the Golgi apparatus, a structure in almost all of the body's cells that packages proteins. He also described the Golgi tendon organ, a sensor that detects tension in tendons, and made important contributions to the study of malaria.

The wrong side of history

Golgi believed his stains showed a continuous nerve network — the reticular theory — and never accepted Cajal's neuron doctrine. When they shared the 1906 Nobel Prize, Golgi used his lecture to attack it. History sided with Cajal, but without Golgi's method Cajal could never have made his case.