[Role of catecholamines, released due to stress, on stimulation of heparin secretion by mast cells in rats]

The secretory status of mast cells of mesentery and subcutaneous connective tissue was studied in rats using the morphometry analysis. Immobilization for 30 min has induced a 3.7-fold decrease of the heparin saturation index in these mast cells and a 3-fold increase of the granulolysis index. In rats preliminary given propranolol, alpha-adrenoceptor antagonist (1.25 mg/kg), a stimulatory effect of immobilization was absent. Phentolamine, alpha-adrenoceptor antagonist (6 mg/kg), partially inhibited the immobilization effect. Isoprenaline, beta-agonist (1.5 mg/kg), activated heparin secretion in rats without immobilization, while phenylephrine, alpha-agonist (2.5 mg/kg) had no effect on the secretory state of mast cells. Propranolol in the same dose also blocked the stimulatory action of i. v. injected alpha-thrombin (50 NIH/kg) on heparin secretion from mast cells of subcutaneous connective tissue. The obtained results show that catecholamines participate in activation of heparin release from mast cells induced both by the stress and by thrombin injection. Their action is mediated by beta-adrenoceptors of the vessel wall.