title: Force-length relations of glycerinated rabbit psoas.
abstract: Force-length curves of glycerinated rabbit psoas were determined in media of physiological interest. In one set of experiments the free [Ca++] was constant at 10(-5) M and the [MgATP] varied. At low [MgATP] the elastic properties are those of a highly ordered, inextensible fiber; at high [MgATP] they are representative of a much more elastic body. At intermediate concentrations sigmoidal shaped curves were observed as were also found when [MgATP] was constant and the free [Ca++] varied. These curves closely resemble coexistence curves that have been reported for fibrous proteins.
mesh_terms: D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D002118:Calcium / Q000494:pharmacology; D004548:Elasticity; D005990:Glycerol; D009119:Muscle Contraction / Q000187:drug effects; D009132:Muscles / Q000187:drug effects; D011817:Rabbits; D013314:Stress, Mechanical
chemical_list: D000255:Adenosine Triphosphate; D005990:Glycerol; D002118:Calcium