[Changes in cholino- and adrenoceptors as affected by blood proteolytic enzymes]. / Izmenenie kholino- i adrenoretseptorov pod deistviem proteoliticheskikh fermentov krovi.

The effects of kallikrein, thrombin, and plasmin on interaction of acetylcholine and noradrenaline with receptors of the isolated portal vein of guinea-pigs were studied. The functional activity of receptors was studied by the pharmacokinetic method. It was found that kallikrein and thrombin do not disturb the kinetics of agonist interaction with receptors, whereas the magnitude of isometric vascular contractions dramatically decreased after plasmin treatment and becomes disproportionate to the concentration of neurotransmitters. Exposure of the portal vein to kallikrein or thrombin caused different changes in the sensitivity and quantity of active cholino- and adrenoreceptors. These proteolytic enzymes reduced the sensitivity of receptors to noradrenaline and increased it to acetylcholine. Exposure to kallikrein brought about a decrease in the quantity of active cholinoreceptors and a rise in the number of adrenoreceptors. The treatment of the vessels with thrombin resulted in a decrease in the number of active adrenoreceptors. The number of active cholinoreceptors remained unchanged.

[Parameters of bradykinin interaction with cardiovascular system receptors]. / Parametry vzaimodeistviia bradikinina s retseptorami serdechno-sosudistoi sistemy.

The equation describing kinetics of interaction between bradykinin and cardiovascular receptors resembles the equations describing depressive adrenergic and some cholinergic reactions in dogs, rabbits and white rats. In this study of bradykinin receptor state, in order to describe quantitatively hypotensive action of different bradykinin doses on interaction of this peptide with receptors, bradykinin had to be injected intraaortally. The data obtained revealed that the greatest efficiency of kininergic reaction occurred in dogs whereas the least--in white rats.