Different character: Golgi And Cajal

Fig. 1

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Camillo Golgi (1842-1926) and Santiago Ramón y Cajal (1852-1934) were jointly awarded the Nobel Prize in Physiology or Medicine for their research on the structure of the nervous system in 1906. This dual award was a first for the Nobel committee. Each of them had their own conception of the nervous system: Golgi believed that the nervous system was comprised of a diffuse network formed by the axonal processes; Cajal defended the individuality of the nerve cell. As result, the corresponding Nobel lectures represented a defense of these two conflicting theories—the reticular and the neuron doctrine.

Golgi discovered the first and unique method of staining nervous cells. He called it the “black reaction”, which was later renamed Golgi’s method or the Golgi stain. Based on his observations, he drew up a reticular theory according to which nerve cells were fused or interlaced in a diffuse nerve network spreading throughout the nervous system. Golgi is renowned amongst the scientific community not only for the discovery of the chrome-silver impregnation method, but also such important contributions as the characterization of two fundamental types of nerve cells, still named after him type I (motor) neurons and Golgi type II (sensory) neurons. Golgi noticed that an intracellular structure existed in neurons that he designated the “internal reticular apparatus” which is known today as the “Golgi apparatus”. He described the “tendinous sensory corpuscles” that bear his name ”Golgi tendon organ” He described what are now known as the Muller-Golgi tubules which are the canaliculi of the parietal cells of the gastric glands. He defined the Golgi-Mazzoni corpuscles used to describe an encapsulated structure, similar to the Pacini corpuscle but found only in the fingertips. In addition, he contributed descriptions of Golgi-Rezzonico filaments in the nerve fibres, the neuropathology of chorea, early peritoneal blood transfusion, and provided many fundamental contributions to the study of malaria, elucidating the cycle of the malarial agent, Plasmodium, in red blood cells.

Fig. 2

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In 1900, Golgi was named Senator [Fig. 1-2]. In his private life, Golgi married Donna Lina Aletti, a niece of scientist Giulio Bizzozero (1846-1901). He loved music and played flute and composed some musical pieces. Golgi was considered an introverted, quite and reserved person. He was depicted as a severe, authoritarian man in public life [Fig. 1-2].

Fifteen years later using Golgi’s method, Cajal became the champion of the nervous theory, according to which the nervous system is composed of individual cells, like any other tissue. In 1887, Cajal had the possibility to see some preparation of nervous tissue impregnated with the Golgi method. Using this technique, he began a systematic study of the nervous system confirming the usefulness of the Italian scientist. He studied how the axons of some small stellate cells located in the molecular layer end freely over the soma of the Purkinje cells, making pericellular contacts.

Fig. 3

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Fig. 4

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Rudolf Alber von Kölliker (1817-1905) called these structures “terminal nets” which were identified as dendritic spines. These anatomical discoveries were published by Cajal in 1888. Another important concept discovered by Cajal was the polarization, nerve impulse is received by the dendrites of the cell, which is transported to the cell body, and through the axon the signal can then be transmitted on beyond the cell. In this way Cajal predicted the direction of the nerve impulse in all system. Cajal presented the so-called Law of Dynamic Polarization at the medical congress in Valencia in 1891. He postulated the growth cone probed the pathway to determine where the nerve fibre had to grow, and that it was attracted to or repelled by certain chemical substance secreted by the cells it encounters along its route. This is the theory of chemotropism formulated in 1892. He formulated the neuronal doctrine that supported the theory of the individuality of the neuron, a concept suggested by William His (1831-1944), Fridtjof Nansen (1861-1930) and August Forel (1848-1937) although they had never demonstrated it. This neuronal theory contrasted with the reticularist that was defended by Golgi and Joseph Gerlach (1820-1896). This theory was presented to the German Anatomical Society Congress celebrated in Berlin in 1889. Cajal’s major discoveries of the nervous system were: individual cells are the basis units of the nervous system; polarization of nerve cells; the cone of growth and its function; the cell organization of the central and peripheral nervous system of different animal species. In his life Cajal was an clever artist and he loved the photography trying the first technical application of colour. Cajal married Silveria Fananas and they had seven children. Cajal was a friendly but outstanding “character” [Fig. 3-4].

Camillo Golgi’s studies permitted to know the histological and anatomical elements on the structure of nervous system marked an era with his preparations stained with the “reazione nera”. Santiago Ramón Cajal discovered new neuroanatomical concept and he is considered one of the founders of modern neurobiology.

References

• De Carlos J A and Borrell J A historical reflection of the contributions of Cajal and Golgi to the foundation of neuroscience. Brain Res Rev 55: 8-16; 2007
• Finger S. Origins of Neuroscience. New York-Oxford, Oxford University Press, 1994
• Katz-Sidlow R J. The formulation of the Neuron Doctrine. Arch Neurol 55: 237-40; 1998
• Kruger L The sensory neuron and the triumph of Camillo Golgi. Brain Res Rev 55: 406-10; 2007
• Mazzarello P. Golgi: a biography of the founder of modern Neuroscience. Oxford University Press, 2010