Clonidine-induced antinociception and locomotor hypoactivity are reduced by dexamethasone in mice

被引:8
作者
Capasso, A [1 ]
Loizzo, A [1 ]
机构
[1] Univ Salerno, Dipartimento Sci Farmaceut, I-84084 Salerno, Italy
关键词
D O I
10.1211/0022357011775587
中图分类号
R9 [药学];
学科分类号
1007 ;
摘要
The effects of dexamethasone pretreatment on clonidine-induced antinociception and locomotor hypoactivity were investigated in mice. In the hot-plate and the tail-flick tests, dexamethasone administered intraperitoneally at a dose of 1 mg kg(-1), 30 or 60 min before clonidine, reduced clonidine antinociception in both tests and reduced clonidine-induced locomotor hypoactivity in the activity cage. When administered 15 min before clonidine, dexamethasone had no effect on clonidine antinociception. A higher dexamethasone dose (10 mg kg(-1)) induced the same effects observed at a dose of 1 mg kg(-1) in the hot-plate and the tail-flick tests, but the former dose had a stronger effect on locomotor hypoactivity. Dexamethasone (10 ng/mouse) administered intracerebroventricularly 30 min before clonidine was also able to reduce both clonidine-induced antinociception and locomotor hypoactivity. The protein synthesis inhibitor, cycloheximide, administered intraperitoneally at the dose of 10 mg kg(-1). 2 h before clonidine, was able to prevent dexamethasone effects on clonidine induced antinociception. The glucocorticoid receptor antagonist RU-38486, administered intracerebroventricularly at the dose of 1 ng/mouse, was also able to block dexamethasone effects on clonidine-induced antinociception and locomotor hypoactivity, whereas both cycloheximide and RU-38486 per se did not influence pain sensitivity or locomotor activity. These results suggest: that the dexamethasone effects on clonidine-induced antinociception and locomotor hypoactivity depend on the stimulating effects that dexamethasone exert, on the protein synthesis via the glucocorticoid receptor in the brain.
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页码:351 / 360
页数:10
相关论文
共 54 条
[1]   DEXAMETHASONE INDUCES BIPHASIC EFFECT ON MORPHINE HYPERMOTILITY IN MICE - A DOSE-RELATED PHENOMENON [J].
CAPASSO, A ;
DIGIANNUARIO, A ;
LOIZZO, A ;
PIERETTI, S ;
SORRENTINO, L .
LIFE SCIENCES, 1991, 49 (19) :1411-1418
[2]   CENTRAL INTERACTION OF DEXAMETHASONE AND RU-38486 ON MORPHINE ANTINOCICEPTION IN MICE [J].
CAPASSO, A ;
DIGIANNUARIO, A ;
LOIZZO, A ;
PIERETTI, S ;
SORRENTINO, L .
LIFE SCIENCES, 1992, 51 (14) :PL139-PL143
[3]   DEXAMETHASONE INCREASES ADENYLYL CYLASE ACTIVITY AND EXPRESSION OF THE ALPHA-SUBUNIT OF GS IN GH3 CELLS [J].
CHANG, FH ;
BOURNE, HR .
ENDOCRINOLOGY, 1987, 121 (05) :1711-1715
[4]   POSSIBLE PHYSIOLOGICAL-ROLE OF ADRENAL AND GONADAL-STEROIDS IN MORPHINE ANALGESIA [J].
CHATTERJEE, TK ;
DAS, S ;
BANERJEE, P ;
GHOSH, JJ .
EUROPEAN JOURNAL OF PHARMACOLOGY, 1982, 77 (2-3) :119-123
[5]   Cellular actions of opioids and other analgesics: Implications for synergism in pain relief [J].
Christie, MJ ;
Connor, M ;
Vaughan, CW ;
Ingram, SL ;
Bagley, EE .
CLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, 2000, 27 (07) :520-523
[6]   SEDATIVE EFFECTS OF ALPHA-SYMPATHOMIMETIC DRUGS AND THEIR ANTAGONISM BY ADRENERGIC AND CHOLINERGIC BLOCKING DRUGS [J].
DELBARRE, B ;
SCHMITT, H .
EUROPEAN JOURNAL OF PHARMACOLOGY, 1971, 13 (03) :356-&
[7]  
DREW GM, 1979, BRIT J PHARMACOL, V67, P133
[8]   EFFECTS OF ALPHA-ADRENOCEPTOR AGONISTS AND ANTAGONISTS ON PRE-SYNAPTICALLY AND POSTSYNAPTICALLY LOCATED ALPHA-ADRENOCEPTORS [J].
DREW, GM .
EUROPEAN JOURNAL OF PHARMACOLOGY, 1976, 36 (02) :313-320
[9]   ENHANCEMENT OF CLONIDINE-INDUCED ANALGESIA BY LESIONS INDUCED WITH SPINAL AND INTRACEREBROVENTRICULAR ADMINISTRATION OF 5,7-DIHYDROXYTRYPTAMINE [J].
DUAN, J ;
SAWYNOK, J .
NEUROPHARMACOLOGY, 1987, 26 (04) :323-329
[10]  
FIELDING S, 1978, J PHARMACOL EXP THER, V207, P899