Inhibitory effect of harmane on morphine-dependent Guinea pig ileum.
Studies on the occurrence and properties of b-carbolines structurally related to harmala alkaloids have gained attention since it was hypothesized that some of these compounds play a role in processes of substance abuse and dependence. This study investigates the effects of harmane on naloxone-precipitated withdrawal syndrome in morphine-dependent guinea pig ileum. Segments of ilea from starved male guinea pigs were obtained and fixed at a resting tension of 1 g in an organ bath containing 10(-6) M morphine in Tyrode solution at 37 degrees C, which was bubbled with 95% O(2) and 5% CO(2). Tissues were incubated in 10(-6) M morphine containing Tyrode solution for 4 hours before harmane was added. Naloxone and harmane had no effect on naive ilea. Naloxone (10(-6) M) contracted morphine-dependent ilea. Harmane significantly inhibited the contractile response to naloxone in a dose-dependent manner (10(-7) M = 24%; 10(-6) M = 49.3%; 10(-5) = 70%). These results suggest that harmane may have beneficial effects on morphine withdrawal syndrome.
Aricioglu
Feyza
F
Department of Pharmacology, Faculty of Pharmacy, Marmara University, Haydarpasa, Istanbul, Turkey. feyzak@turk.net
Utkan
Tijen
T
D000317:Adrenergic alpha-Antagonists / Q000378:metabolism / Q000494:pharmacology; D000701:Analgesics, Opioid / Q000378:metabolism; D000818:Animals; D006168:Guinea Pigs; D006247:Harmine / Q000031:analogs & derivatives* / Q000378:metabolism* / Q000494:pharmacology*; D019329:Idazoxan / Q000378:metabolism / Q000494:pharmacology; D007082:Ileum / Q000187:drug effects*; D066298:In Vitro Techniques; D008297:Male; D009020:Morphine / Q000378:metabolism; D009021:Morphine Dependence; D009119:Muscle Contraction / Q000187:drug effects / Q000502:physiology; D009270:Naloxone / Q000378:metabolism; D009292:Narcotic Antagonists / Q000378:metabolism; D013375:Substance Withdrawal Syndrome; D015016:Yohimbine / Q000378:metabolism / Q000494:pharmacology
D000317:Adrenergic alpha-Antagonists; D000701:Analgesics, Opioid; D009292:Narcotic Antagonists; D015016:Yohimbine; D009270:Naloxone; D006247:Harmine; D009020:Morphine; C005010:harman; D019329:Idazoxan