The experiments were carried out on 15 rats aged between 4–6 months. Myometrial tissue (1,5– 2 cm long) was set up in 4 isolated organ baths (20 ml) at 37 ^oC. After recording the pattern of myometrial tissue spontaneous motility: salbutamole –β2-adrenergic receptors agonist, dobutamine –β₁-adrenergic receptors agonist, propranolol –β₁ – and β₂-adrenergic receptors antagonist, isoprenaline –β₁ and β₂-adrenergic receptors agonist, adrenaline –α and β-adrenergic receptors agonist were added into the organ baths. The dose of the formulae was fixed in preliminary experiments. Adrenergic receptor activated by salbutamole selective agonist caused decrease in myomerial motility. On the other hand adrenergic receptor blocked by propranolol eliminated the restraining influence of salbutamole on myometrial motility. Adrenergic receptor activated by dobutamine selective agonist caused decrease in uterus motility. Adrenergic receptor blocked by propranolol antagonist eliminated the restraining influence of dobutamine on uterus. Adrenergic receptor activated by isoprenaline and adreneline also caused decrease in uterus motility. The experiments exhibited the presence of both the adrenergic receptor subtypes (β₁ and β₂) in the myometrial of rats. Adrenergic receptor activated by β-adrenergic agonist caused decrease in uterus motility.

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