Inhibitory effects of MK-801 on contextual sensitization to climbing behavior and on development of tolerance to hypothermia induced by a single high dose of apomorphine.
A single high dose of apomorphine (10 mg x kg(-1)) produced not only contextual sensitization to and conditioning of climbing behavior, but also context-independent tolerance to hypothermia. MK-801 (0.15 and 0.3 mg x kg(-1)) inhibited contextual sensitization to and conditioning of climbing behavior. Development of tolerance to hypothermia was also inhibited by MK-801. Dopamine D1 antagonist, SCH23390 (0.5 mg x kg(-1)), but not D2 antagonist, sulpiride, inhibited sensitization to and conditioning of climbing behavior. D2 antagonist, sulpiride (50 mg x kg(-1)), but not D1 antagonist, SCH23390, inhibited development of tolerance to hypothermia. These results suggest that MK-801 inhibited contextual sensitization to climbing behavior and development of tolerance to hypothermia through glutamatergic modulation of dopaminergic functions at dopamine receptors.
Yun
J S
JS
College of Pharmacy, Chungbuk National University, Cheongju, Korea.
Kim
H S
HS
Lee
M K
MK
Oh
K W
KW
Jang
C G
CG
Park
W K
WK
Seong
Y H
YH
Lee
S C
SC
Oh
S K
SK
D000818:Animals; D001058:Apomorphine / Q000494:pharmacology; D001552:Benzazepines / Q000494:pharmacology; D003213:Conditioning, Psychological / Q000187:drug effects*; D003864:Depression, Chemical; D016291:Dizocilpine Maleate / Q000494:pharmacology*; D004298:Dopamine / Q000378:metabolism; D018491:Dopamine Agonists / Q000494:pharmacology; D018492:Dopamine Antagonists / Q000494:pharmacology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology*; D007035:Hypothermia / Q000139:chemically induced / Q000378:metabolism*; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D009043:Motor Activity / Q000187:drug effects*; D017447:Receptors, Dopamine D1 / Q000187:drug effects; D017448:Receptors, Dopamine D2 / Q000187:drug effects; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism; D013469:Sulpiride / Q000494:pharmacology
D001552:Benzazepines; D018491:Dopamine Agonists; D018492:Dopamine Antagonists; D018691:Excitatory Amino Acid Antagonists; D017447:Receptors, Dopamine D1; D017448:Receptors, Dopamine D2; D016194:Receptors, N-Methyl-D-Aspartate; D016291:Dizocilpine Maleate; D013469:Sulpiride; D001058:Apomorphine; D004298:Dopamine