title: Possible involvement of amine oxidase inhibition in the sympathetic activation induced by khat (Catha edulis) chewing in humans.
abstract: The possibility that phenylalkylamines (cathinone and cathine) of khat, like amphetamines, are amine oxidase inhibitors with clinical significance is evaluated. Results show that khat chewing induces a significant increase in blood pressure, body temperature and urinary catecholamines in khat naive subjects. On the other hand, in habitual consumers a significant enhancement only of blood pressure is observed. Urinary concentrations of vanilmandelic acid show an inhibitory trend in both groups of subjects. This has been related to a decrease in catecholamine deamination. In fact, oxidative deamination of benzylamine catalyzed by beef plasma amine oxidase is non-competitively inhibited in vitro by cathinone (Ki = 0.05 mM) and cathine (Ki = 10 mM) as well as by amphetamine (Ki = 7.9 mM).
mesh_terms: D000328:Adult; D006631:Amine Oxidase (Copper-Containing); D000661:Amphetamine / Q000494:pharmacology; D002395:Catecholamines / Q000378:metabolism; D029754:Catha; D000697:Central Nervous System Stimulants / Q000494:pharmacology*; D006801:Humans; D008297:Male; D000587:Oxidoreductases Acting on CH-NH Group Donors / Q000037:antagonists & inhibitors*; D010936:Plant Extracts; D013564:Sympathetic Nervous System / Q000187:drug effects*
chemical_list: D002395:Catecholamines; D000697:Central Nervous System Stimulants; D010936:Plant Extracts; D000661:Amphetamine; D006631:Amine Oxidase (Copper-Containing); D000587:Oxidoreductases Acting on CH-NH Group Donors