[Study of the changes in the membrane permeability of smooth muscle cells for Ca45 and Na22 isotopes under the action of catecholamines].

Relaxation of smooth muscles of the stomachal band, but not of the portal vein of rats, induced with isadrine, is accompanied by a reduced entrance of Ca45 into the cells, this process, however, being barred by propranol. Contraction of smooth muscles of the seminal duct, aortic band and that of the portal vein of the rats, induced by norepinephrine is attended by an intensified incorporation of Ca45 in the cells, which diminishes in the presence of phentolamine. Norepinephrine stimulates an insignificant increase of the Na22 entrance into the cells of the portal vein and does not produce any regular changes in the movement of this isotope in the cells of the seminal duct of the rats.