Fernando de Castro Rodríguez was born in Madrid, the capital city of Spain, on February 25th 1896. Around 1916, while studying his degree in Medicine (M.D.), the young de Castro joined the research group of the neuropathologist Nicolás Achúcarro at the Laboratorio de Investigaciones Biológicas, directed by Santiago Ramón y Cajal, awarded with the 1906 Nobel Prize in Physiology or Medicine. Fernando de Castro progressed fast with histological techniques and the early and finally fatal illness of Achúcarro (dead in 1918) made that Cajal adopted De Castro as his own Ph.D. student. The relationship between The Maestro and his young pupil dured for the rest of the life of Cajal (dead in October 1934): Fernando de Castro never left the Cajal Institute for more tan a few months long.

In 1922, De Castro obtained his Ph.D. degree at the Universidad de Madrid (currently named Universidad Complutense) with a doctoral thesis studying the structure of sensitive and sympathetic ganglia in normal and pathological condition. This research granted Fernando de Castro with the international recognition, considered for decades as the top world-wide specialist in the field together with the Russian Lawrentjev. Not in vain, it was in the mid 1920 when Wilder Penfield worked with Pío del Río-Hortega, knew Cajal and De Castro and invited the latter to write two chapters on the sturecture of peripheral ganglia in his celebrated treaty on Neurology. This recognition remained almost intact in the 1960s, when Penfield renewed the entrustment for the secoind edition of his textbook. But it should be considered that the research of Fernando de Castro on this discipline granted something even more valuable for him: the special distinction of Cajal, who based in the unusual skills on Histology developed by his young disciple, chose De Castro to publish together the book "Elementos de técnica micrográfica del sistema nervioso" in1933. This book compiles all the techniques and protocols developed by the Cajal School or Spanish Neurological School, and is part of this Project granted by FENS.

Also in the middle 1920s, Fernando de Castro started to study the sensory nature of the innervation of the aorto-carotid region. He identified and distinguished between the baroreceptors (which detect changes in the arterial pressure) and the chemoreceptors (which detect changes in the chemical composition of blood), and localised the latter situated in a minuscule structure linked to the light of the internal carotid artery called "glomus caroticum" or carotid body. This should be considered as De Castro´s outmost scientific contribution, because his was the first description of an arterial chemoreceptor. With this, Fernando de Castro established the anatomical basis of the cardio-respiratory reflexes recently described by the German physiologist Heinrich Hering. De Castro´s findings inspired Corneille Heymans to study the carotid body as the key for the chemosensory reflexes: it was only after the stage of Fernando de Castro at Heymans´ laboratory at Ghent University when the Belgian physio-pharmacologists reoriented research in the way that bring Corneille Heymans to be awarded with the Nobel Prize in Medicine in 1938. Without the meticulouse work of Fernando de Castro and his hypothesis on the carotid body as the site for the arterial chemoreceptors, Heymans´ demonstration should be largely more difficult and take more time: this is the reason for which many in the international scientific community consider that Fernando de Castro and Corneille Heymans should share the Nobel Prize.

Other scientific problems attacked by Fernando de Castro in different moments of his scientific career were the organization and development of neuroglia at the olafctory bulb and cortex, the regeneration of axons (and the nervous system in general) and the structure of synapses.

The Spanish Civil War, Fernando de Castro and Jorge Francisco Tello were the only disciples of Cajal who defended the Cajal Institute (including all the equipement and belongins): they accomplied this task with stoic efficacy and defiating perils derived from the condition of Madrid as battle front during almost the entire war. Once finalized the war, Fernando de Castro funded the Cajal Museum, within the Cajal Institute, while he was deposed from his chair at the university due to political repression; it was not until 1950 when De Castro recovered his position at the Universidad de Madrid.

Till his death in 1967, Fernando de Castro maybe was the most genuine representant of the Cajal School, always interested in the veneration of the universal Aragonian. This was the motor to organize in 1952 a fruitful international symposium to commemorate the first century of Cajal´s birth: this scientific meeting was held in Madrid and a number of Nobel awardees in Medicine possitively responded to De Castro´s call in such a delicate situation of Spain in the international scenario at that time. Besides this, Fernando de Castro tried to actively perpetuate Cajal´s memory and example, which successfully reached with a series of disciples and collaborators recruited and formed with him, like the eminent morphologists Constantino Sotelo and Facundo Valverde or the physiologists Antonio Gallego and Antonio Fernández de Molina, among others.

International recognition after the IInd World War came to de Castro by hand of the  Fédération Mondiale de Neurologie (Neuropathology Committee), the Academia Nazionale dei Linceii (Italy) and the International Brain Research Organization-IBRO, among a number of institutions from other countries (Chile, Peru, Argentina, Colombia) in recognition of the research achievements of Fernando de Castro, as well as his colleagues, like Corneille Heymans, Lord Adrian, Giusseppe Levi, who due to the direct action of De Castro, came to Madrid in 1952 (a moment in which Spain still was politically isolated for political reasons) to commemorate the first century of Cajal´s birth at CSIC (Madrid). In this context and also in 1952, Fernando de Castro convinced CSIC and authorities in Spain to re-publish Cajal opus magna (“Histologie du Systeme Nerveux de l´homme et des Vertebrés”).

De Castro was also designed as the head of the official commission to attend the Nobel ceremony in Stockholm (Sweden), 1959, where the Spanish-born Severo Ochoa was awardeed with the Nobel Prize in Physiology or Medicine. After awarding him with six research prizes along his career (Rodríguez Abaytúa -1923-, Martínez y Molina -1924-, Obieta -1941-, Santiago Ramón y Cajal -1947- and the prize of the Academy -1949-), Fernando de Castro was finally ellected academic member by the Real Academia Nacional de Medicina-RANM (Spain) in 1964 and one year before by the Real Academia de Ciencias Exactas, Físicas y Naturales (Spain).

Months after officially retired from his universitary responsabilities, Fernando de Castro died in Madrid (Spain) on April 15th, 1967 due to a renal cancer.



  1. de Castro, F. (1981) La Escuela Neurológica Española. Editorial de la Universidad Complutense, Madrid (Spain). ISBN 84-7491-014-5.
  2.   de Castro, F. (2009) Towards the sensory nature of the carotid body: Hering, De Castro and Heymans. Front. Neuroanat. 3:23 (1-11) (doi:10.3389/neuro.05.023.2009).
  3.  Gómez Santoz, M. (2009) Fernando de Castro. Su vida y su obra. Ed. Fundación Mutua Madrileña, Madrid (Spain). 

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