Involvement of 5-hydroxytryptamine neuronal system in Delta(9)-tetrahydrocannabinol-induced impairment of spatial memory.
The present study investigated the involvement of the serotonin (5-hydroxytryptamine, 5-HT) neuronal system in the Delta(9)-tetrahydrocannabinol-induced impairment of spatial memory in the eight-arm radial maze in rats. Delta(9)-Tetrahydrocannabinol (6 mg/kg, i.p.), which impairs spatial memory, significantly increased the 5-HT content in the ventral hippocampus. A microdialysis study showed that Delta(9)-tetrahydrocannabinol (6 mg/kg, i.p.) decreased 5-HT release in the ventral hippocampus. The 5-HT precursor, 5-hydroxy-L-tryptophan (5-HTP; 50 mg/kg, i.p.), the 5-HT re-uptake inhibitor, clomipramine (0.01 and 0.1 mg/kg, i.p.), the 5-HT receptor agonist, 5-methoxy-N,N-dimethyltryptamine (5-MeODMT; 0.01 and 0.03 mg/kg, i.p.), and the 5-HT(2) receptor agonist, 1-(2,5-dimethoxy 4-iodophenyl)-2-amino propane (DOI; 10 microg/kg, i.p.), significantly attenuated the Delta(9)-tetrahydrocannabinol-induced impairment of spatial memory. These results suggest that the 5-HT neuronal system may be involved in the Delta(9)-tetrahydrocannabinol-induced impairment of spatial memory.
Egashira
Nobuaki
N
Department of Physiology and Pharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, Japan.
Mishima
Kenichi
K
Katsurabayashi
Shutaro
S
Yoshitake
Tomohiro
T
Matsumoto
Yoshiaki
Y
Ishida
Junichi
J
Yamaguchi
Masatoshi
M
Iwasaki
Katsunori
K
Fujiwara
Michihiro
M
D006916:5-Hydroxytryptophan / Q000494:pharmacology; D000818:Animals; D013759:Dronabinol / Q000494:pharmacology*; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D018782:Maze Learning / Q000187:drug effects / Q000502:physiology; D008568:Memory / Q000187:drug effects* / Q000502:physiology; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D012701:Serotonin / Q000378:metabolism*; D017366:Serotonin Receptor Agonists / Q000494:pharmacology; D017367:Selective Serotonin Reuptake Inhibitors / Q000494:pharmacology; D013037:Spatial Behavior / Q000187:drug effects / Q000502:physiology
D006916:5-Hydroxytryptophan; D013759:Dronabinol; D012701:Serotonin; D017366:Serotonin Receptor Agonists; D017367:Selective Serotonin Reuptake Inhibitors