adrenergic beta receptor drug pathway - beta-agonist and beta-blocker 2010-06-30T10:47:27Z PW:0000799 The pharmacokinetics and pharmacodynamics pathway of adrenergic beta receptors drugs - beta-agonists and blockers. Adrenergic beta receptors, in response to epinephrine or norepinephrine couple to the Gs alpha subunit of heterotrimeric G protein to elicit several responses. Beta-agonists are used to stimulate while beta-blocker antagonists are used to inhibit these responses, as necessary. Genetic variations can result in changes in drug availability and can cause differences in the response of the organism to the drug. pathway vpetri cardiovascular system drug pathway respiratory system drug pathway