On certain points connected with the Coagulation of the Blood

Calcium and muscle contraction: the triumph and tragedy of Lewis Victor Heilbrunn

Lewis Victor Heilbrunn has been called the pioneer of Ca²⁺ as an intracellular regulator (Campbell AK. Cell Calcium 7: 287-296, 1986; Campbell AK. Intracellular Calcium, 2015). In 1947, he was the first to provide convincing evidence that Ca²⁺ triggered muscle contraction (Heilbrunn LV, Wiercinski FJ. J Cell Comp Physiol 29: 15-32, 1947). Yet his work was met mostly with silence and neglect. One wonders why. Heilbrunn was a general physiologist who believed in the uniformity of nature with regard to movement. He believed that ". . . the theory of what makes cells divide should not be very different from the theory of what makes muscle contract . . ." (Heilbrunn LV. The Dynamics of Living Protoplasm, 1956). He did not believe that one could understand how the living machine worked by investigating its parts. He believed that, to understand life, one must study the dynamics of living protoplasm. The origin and evolution of Heilbrunn's thought process regarding the role of Ca²⁺ as a physiological activator will be traced back to the 1920s. The ways in which he tested the Ca²⁺ hypothesis in sea urchin eggs in the 1920s and 1930s will be explored. This work shaped Heilbrunn's thinking about the role of Ca²⁺ in muscle contraction. Importantly, why he and his results were ignored for years will be examined. It turned out that being right was not enough. Bad luck and a stubborn belief in an outmoded scientific philosophy contributed to the neglect.