Summary: Adrenoceptors a receptors a, receptors: vasoconstriction: increased peripheral resistance, BP r, contraction of radial muscle of iris: mydriasis a2 receptors: CNS, presynaptic membranes of adrenergic nerves: vasodilatation inhibition of ne release inhibition of insulin release receptors • 1 receptors: vasoconstriction: increased peripheral resistance, BP↑; contraction of radial muscle of iris: mydriasis • 2 receptors: CNS, presynaptic membranes of adrenergic nerves: vasodilatation, inhibition of NE release; inhibition of insulin release Summary: Adrenoceptors 11