title: [Diffusion of fluorescein molecules in muscle fiber. II. The ratio of the coefficient of diffusion to the fiber diameter].
abstract: The diffusion of sodium fluorescein was studied upon alteration of the medium tonicity and the fibre stretching. In the former case, coefficients of both translational (Dt) and of rotational (Dr) diffusion changed, but not equally. With a decrease of the fibre diameter on hypertonia, Dt is reduced more drastically than Dr, which means that the diffusion anisotropy (see formula in text) is diminished. On stretching muscle fibres, provided their volumes are constant, the diffusion rate is not changed. It is concluded that the surface-ordered water in muscle fibre capillaries, in which dye molecules are diffusing, becomes desorganized in the process of hypertonic contraction due to the increase of ionic concentration (potassium, for the most time).
mesh_terms: D000818:Animals; D004058:Diffusion; D005452:Fluoresceins / Q000378:metabolism*; D066298:In Vitro Techniques; D007424:Intracellular Fluid / Q000378:metabolism; D009129:Muscle Tonus; D009132:Muscles / Q000378:metabolism*; D011896:Rana temporaria
chemical_list: D005452:Fluoresceins
vernacular_title: Diffuziia molekul fluorestseina v myshechnom volokne. II. Zavisimost' koéffitsienta diffuzii ot diamtera volokna.