Pharmacological mechanism in slip-down behavior of mice.
Slip-down from a raised platform was previously found in mice treated with morphine, and this behavior was also recognized in mice treated with a monoamine releaser methamphetamine. Pharmacological examination on the slip-down indicated that the behavior was induced by receptor stimulations by D2 agonist PPHT and 5HT-2 agonist DOI. In mice treated with PPHT, antagonists of D1, alpha2, 5HT-2 and opioid mu and kappa suppressed the behavior. In mice treated with DOI, antagonists of D1, alpha2, 5HT-1A, 5HT-3 and opioid mu and delta suppressed the behavior. These present findings suggest that the slip-down was mainly induced by opioid mu receptor activity regulated with monoamine activities. When the slip-down is considered as an anxious behavior, it may be also suggested that the anxiety induced by 5-HT activities furthermore stimulated the behavior via the other opioid receptor activities.
Masuda
Yutaka
Y
Psychosomatic Division, Department of Neuropsychiatry, Akita University School of Medicine, Akita 010-8543, Japan.
Suzuki
Minoru
M
Takemura
Takaubu
T
Sugawara
Junya
J
Guo
Naxin
N
Liu
Yang
Y
Kawarada
Yoshihikio
Y
Shimizu
Tetsuo
T
Sugiyama
Toshihiro
T
D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D018491:Dopamine Agonists / Q000494:pharmacology*; D018492:Dopamine Antagonists / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D008297:Male; D008694:Methamphetamine / Q000494:pharmacology; D051379:Mice; D008815:Mice, Inbred Strains; D009043:Motor Activity / Q000187:drug effects*
D018491:Dopamine Agonists; D018492:Dopamine Antagonists; D008694:Methamphetamine