Muscarinic cholinergic and histaminergic H1 and H2 receptors are not involved in the LH response to naloxone in man.
The role of muscarinic-cholinergic and H1-, H2-histaminergic receptors as possible mediators of the LH response to the opioid antagonist naloxone was evaluated in 18 normal men. Subjects were divided in 3 groups of 6 men; the increment of LH in the plasma elicited by naloxone was evaluated after giving naloxone alone or together with dexchlorpheniramine, cimetidine or pirenzepine (respectively H1-, H2-histaminergic and muscarinic-cholinergic receptor antagonists). LH release was significantly stimulated by naloxone in all subjects; this response was not altered by histaminergic or cholinergic blockade. These results confirm the stimulatory effect of naloxone on LH release in man, without evidence of the involvement of H1-, H2-histaminergic or muscarinic-cholinergic pathways.
D000328:Adult; D002744:Chlorpheniramine / Q000494:pharmacology; D002927:Cimetidine / Q000494:pharmacology; D006801:Humans; D007986:Luteinizing Hormone / Q000097:blood*; D008297:Male; D009270:Naloxone / Q000494:pharmacology*; D010890:Pirenzepine / Q000494:pharmacology; D011968:Receptors, Histamine / Q000502:physiology*; D011969:Receptors, Histamine H1 / Q000502:physiology*; D011970:Receptors, Histamine H2 / Q000502:physiology*; D011976:Receptors, Muscarinic / Q000502:physiology*
D011968:Receptors, Histamine; D011969:Receptors, Histamine H1; D011970:Receptors, Histamine H2; D011976:Receptors, Muscarinic; D009270:Naloxone; D010890:Pirenzepine; C018904:dexchlorpheniramine; D002744:Chlorpheniramine; D002927:Cimetidine; D007986:Luteinizing Hormone