H₃ receptors

Question

H₃ receptors

Quizplus · Accepted Answer

H₁ receptors are involved in inflammation and allergic reactions,producing wheal and flare reactions in the skin,bronchoconstriction and mucus secretion,nasal congestion and irritation,and hypotension in anaphylaxis. H₂ receptors regulate gastric acid secretion and feedback control of histamine release. H₃ receptors may be autoreceptors for cholinergic neurotransmission in the airway at the autonomic ganglia,involved in central nervous system functioning and feedback control of histamine synthesis and release. The typical antihistamine found in cold medications is an H₁-receptor antagonist.Examples are pyrilamine and chlorpheniramine.H₂-receptor antagonists include cimetidine (Tagamet)and ranitidine (Zantac),which are used to block gastric acid secretion when treating ulcers.

H3 Receptors

H₃ Receptors