Bezold, Albert von

(b. Ansbach, Bavaria. 7 January 1836; d. Würzburg, Bavaria, 2 March 1868)

physiology.

Bezold’s father, Johann Daniel Christoph, was a physician in Rothenburg and Ansbach. After attending secondary school at Ansbach, Albert began to study medicine at the University of Munich in 1853, with the aim of devoting himself to experimental research; he transferred to Würzburg the following year. At the beginning of 1854 he contracted rheumatic endocarditis, which recurred several times. The ailment led to a mitral stenosis, which resulted in his death at the age of thirty-two.

For the completion of his studies Bezold went in the fall of 1857 to Berlin, where he worked under the physiologist Emil Du Bois-Reymond, famous for his electrophysiological investigations: from him Bezold learned to apply physical methods to the study of biological phenomena. In 1858 Du Bois-Reymond made him an assistant in his institute and in 1859, at the age of twenty-three, he received a surprise appointment to the newly created chair of physiology at the University of Jena. Before he assumed his post in Jena, he went for several days to Würzburg to complete the requirements for the M.D. by presenting the dissertation “Über die gekreuzten Wirkungen des Rückenmarks.” He had tried by experimental means to elucidate the cross effects of the motor and sensory paths while studying there. In 1865 Bezold was called to the new chair of physiology in Würzburg. Although he was active there for only three years, he made it a renowned center for physiological research.

Bezold’s investigations were primarily on the physiology of the nerves and muscles, as well as of the heart. At Würzburg he also made pharmacological investigations, especially on the effects of veratrine, atropine, and curare on the muscles, nerves, and the heart and circulatory system. He confirmed Pflüger’s law in Untersuchungen über die elektrische Erregung der Nerven und Muskeln (1861) and demonstrated that it is also valid for the direct stimulation of the muscle fiber.

In the physiology of the heart, Bezold occupied himself primarily with the problem of which nerve impulses influence the work of the heart. Galen had assumed that the contractions of the heart were independent of the brain. When Bezold turned to these problems, intracardial sources of heart stimulation had already been described; he localized them in the collection of ganglia in the septum interatriale (Bezold’s ganglia). Through cleverly planned experiments Bezold settled the controversy over the relationship between the vagus nerve and the heartbeat. He proved that stimulation of the vagus decreases the rate of heartbeat and that it depresses the total energy output of the heart. In the Untersuchungen über die Innervation des Herzens (1863), Bezold also presented his experiments on the function of the sympathetic nerve, from which he concluded that stimulation of the cervical sympathetic would increase the frequency and the force of the heartbeat.

Bezold’s experiments with veratrine led to the discovery of an effect on the circulation that originated from the heart and was characterized by bradycardia and lowering of the blood pressure. In the heart, veratrine stimulates the sensory (“depressing”) vagus fibers and thus stimulates the vagus center. The efferent component of the reflex, via the vagus tract, decreases the heartbeat; through the vasomotor center, it lessens the tone of the vessels and thus decreases the blood pressure. In 1937 the pharmacologist Adolf Jarisch reexamined this regulatory heart-circulation reflex and recognized its general significance; today it has become important, as the “Schonreflex” (protective reflex) of the heart, for the understanding of pathological processes and is known as the Bezold-Jarisch reflex.

BIBLIOGRAPHY

I. Original Works. Among Bezold’s writings are Untersuchungen über die elektrische Erregung der Nerven und Muskeln (Leipzig, 1861); Untersuchungen über die Innervation des Herzens, 2 vols. (Leipzig, 1863); and “Über die Physiologischen Wirkungen des essigsäuren Veratrins,” written with L. Hirt, in Untersuchungen aus dem physiologischen Laboratorium in Würzburg (Leipzig, 1867), pp. 73–123.

A complete bibliography of his writings is in Robert Herrlinger and lrmgard Krupp, Albert von Bezold, pp. 123–124; see also pp. 113–114.

II. Secondary Literature. Works on Bezold are Paul Diepgen, Unvollendete (Stuttgart, 1960), pp. 34–37; Robert Herrlinger, “Albert von Bezold und die Entdeckung der Innervation des Herzens,” in Von Boerhaave bis Berger, ed. K. E. Rothschuh (Stuttgart, 1964), pp. 106–120: Robert Herrlinger and lrmgard Krupp. Albert van Bezold (Stuttgart, 1964); and Friedrich von Recklinghausen, “Gedächtnisrede auf Albert von Bezold, in Verhandlungen der physikalisch-medizinischen Gesellschaft in Wärzburg, n.s. 1 (1869), xli-xlviii.

Johannes Steudel