Influence of histamine, cimetidine and pyrilamine on naloxone-induced jumping in morphine-dependent mice.
In the present study, the effects of histamine on naloxone-induced jumping in the presence or absence of adrenoceptor or acetylcholine receptor antagonists in morphine-dependent mice were examined. In these experiments, the drugs were used before s.c. injection of naloxone (2 mg/kg), to test their effects on the expression of jumping. The i.c.v. administration of histamine (5-20 microg/mouse) 15 min before naloxone injection decreased the number of jumps in mice. When the histamine H(2) receptor antagonist, cimetidine (5-20 mg/kg), and the histamine H(1) receptor antagonist, pyrilamine (5-20 mg/kg), were administered i.p. to morphine-dependent mice, only cimetidine enhanced the jumping behaviour. Administration of cimetidine (20 mg/kg, i.p.), 30 min, of the beta-adrenoceptor antagonist, propranolol (2.5-10 mg/kg, i.p.), 15 min but not of pyrilamine (20 mg/kg, i.p.), 30 min before naloxone injection, decreased the histamine effect. The i.p. administration of an acetylcholine receptor antagonist, atropine (5 and 10 mg/kg, i.p.), the alpha(1)-adrenoceptor antagonist, prazosin (0.5, 1 and 2 mg/kg, i.p.), and alpha(2)-adrenoceptor antagonist, yohimbine (0.5, 1 and 2 mg/kg, i.p.), 15 min before naloxone injection, had no effect on the histamine response. Single administration of propranolol, atropine or prazosin decreased, while yohimbine increased the naloxone-induced jumping. It is concluded that the histamine H(2) receptor mechanism may be involved in the influence of histamine on the expression of naloxone-induced jumping in morphine-dependent mice.
Zarrindast
Mohammad Reza
MR
Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, P.O. Box 13145-784, Tehran, Iran. zarinmr@ams.ac.ir
Assadi
Elham
E
Oryan
Shahrbano
S
Torkaman-Boutorabi
Anahita
A
Sahebgharani
Mousa
M
D000818:Animals; D001285:Atropine / Q000008:administration & dosage / Q000493:pharmacokinetics; D002927:Cimetidine / Q000008:administration & dosage / Q000493:pharmacokinetics*; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D004338:Drug Combinations; D004347:Drug Interactions; D006632:Histamine / Q000008:administration & dosage / Q000493:pharmacokinetics*; D006635:Histamine H2 Antagonists / Q000008:administration & dosage / Q000493:pharmacokinetics; D007274:Injections, Intraperitoneal; D007276:Injections, Intraventricular; D007279:Injections, Subcutaneous; D051379:Mice; D009020:Morphine / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics; D009021:Morphine Dependence / Q000503:physiopathology*; D009043:Motor Activity / Q000187:drug effects*; D009270:Naloxone / Q000008:administration & dosage / Q000009:adverse effects* / Q000037:antagonists & inhibitors; D011224:Prazosin / Q000008:administration & dosage / Q000493:pharmacokinetics; D011433:Propranolol / Q000008:administration & dosage / Q000493:pharmacokinetics; D011738:Pyrilamine / Q000008:administration & dosage / Q000493:pharmacokinetics*; D011970:Receptors, Histamine H2 / Q000187:drug effects; D015016:Yohimbine / Q000008:administration & dosage / Q000493:pharmacokinetics
D004338:Drug Combinations; D006635:Histamine H2 Antagonists; D011970:Receptors, Histamine H2; D015016:Yohimbine; D009270:Naloxone; D009020:Morphine; D001285:Atropine; D002927:Cimetidine; D006632:Histamine; D011433:Propranolol; D011738:Pyrilamine; D011224:Prazosin