title: Indirect biochemical evidence that reserpine methiodide produces selective depletion of peripheral biogenic amines in rats.
abstract: Reserpine, an alkaloid from Rauwolfia serpentina was widely used for its antihypertensive action in the past. In the present investigation, reserpine methiodide (RMI), a quaternary analogue of reserpine was synthesised and evaluated biochemically for its central and peripheral amine depleting actions in rats and compared with reserpine. The 24 h urinary excretion of vanillylmandelic acid (VMA), 5-hydroxyindoleacetic acid (5-HIAA) and homovanillic acid (HVA), the respective metabolites of noradrenaline, serotonin and dopamine were estimated and considered as indirect biochemical indices for the amine depleting action of reserpine and RMI. The results indicate that RMI at doses of equal to and double the equimolar doses of reserpine was found to deplete the peripheral amines without affecting the central stores of the amines. The results further suggest that the quaternization of reserpine might restrict its transfer across the blood-brain barrier and could be the reason for its selective peripheral action.
authors.affiliation: Pharmacology Division, Department of Pharmaceutical Sciences, Andhra University, Visakhapatnam, Andhra Pradesh, India.
authors.forename: S
authors.initials: S
authors.lastname: Sreemantula
authors.forename: K M
authors.initials: KM
authors.lastname: Boini
authors.forename: S
authors.initials: S
authors.lastname: Koppula
authors.forename: E K
authors.initials: EK
authors.lastname: Kilari
authors.forename: S
authors.initials: S
authors.lastname: Nammi
mesh_terms: D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology*; D014150:Antipsychotic Agents / Q000494:pharmacology*; D001679:Biogenic Amines / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D004298:Dopamine / Q000032:analysis; D005260:Female; D006719:Homovanillic Acid / Q000652:urine; D006897:Hydroxyindoleacetic Acid / Q000652:urine; D007454:Iodides / Q000494:pharmacology*; D008297:Male; D009638:Norepinephrine / Q000378:metabolism; D051381:Rats; D012110:Reserpine / Q000494:pharmacology*; D012701:Serotonin / Q000378:metabolism; D014642:Vanilmandelic Acid / Q000652:urine
chemical_list: D000959:Antihypertensive Agents; D014150:Antipsychotic Agents; D001679:Biogenic Amines; D007454:Iodides; D012701:Serotonin; D006897:Hydroxyindoleacetic Acid; D014642:Vanilmandelic Acid; D012110:Reserpine; D004298:Dopamine; D009638:Norepinephrine; D006719:Homovanillic Acid