An ultrastructural study: the effects of ouabain perfusion on guinea pig myocardium
Models of muscle contraction were proposed as early as the third century B.C. by an Alexandrian physician, Erasistratus, who believed contraction was evoked by the passage of air into the muscle from surrounding blood vessels. Other historical investigators proposed equally supernatural explanations which involved the passage of "animal spirits" into the muscle. It was not until the mid-1800's that Kuhne successfully extracted a contractile protein which he called myosin. From these modest beginnings have evolved models for muscle contraction.