The discovery of vasomotor nerves

The relative contribution of Claude Bernard and Charles Edouard Brown-Séquard to the discovery of vasomotor nerves is described and discussed. The controversy surrounding these two founding fathers of autonomic physiology and pharmacology is also summarized. In 1851, Bernard showed that section of the cervical sympathetic nerve unexpectedly elicited a marked and rapid increase in skin temperature. In 1852, Brown-Séquard extended these observations and established the relationship between blood vessels and the sympathetic nervous system. Thus, Brown-Séquard was the first to demonstrate the existence of sympathetic vasoconstrictor fibres. In contrast, Bernard discovered vasodilator nerves and is the founder of the modern concept of vasomotricity.