Quercetin, a biot1avonoid (100-300 mg/kg) produced dose dependent increase in tail-flick latency, the analgesic effect bei ng sensitive to reversa l by naloxone (1 mg/kg) . Prior trea tment with haloperidol (I mg/kg), 0 1/02 receptor antagoni st haloperidol , sulpiridc (50 mg/kg), a selective O2 receptor antagonist, yohimbine (5 mg/kg), a a2-adrenoreceptor antagoni st but not by SCH 23390 a, se...

Acute stress affects cellular integrity in many tissues including the liver, but its underlying mechanism is still unclear. The aim of the present study was to investigate the potential involvement of catecholamines and adrenoceptors in the regulation of acute restraint stress-induced liver injury. Restraint was achieved by placing mice in restraint tubes. Mice were treated with either an α-l a...

UNLABELLED Agonism of alpha-adrenoreceptors has a powerful anesthetic result mediated, in part, by effects on the spinal cord. Alpha-adrenoreceptor agonists (e.g., dexmedetomidine) can decrease the minimum alveolar anesthetic concentration (MAC) of inhaled anesthetics (e.g., halothane) to zero, with an apparently additive interaction between halothane and dexmedetomidine. We tested whether the ...

Experiments were carried out on the isolated rabbit papillary muscle driven at 0.5 Hz in order to further elucidate the mechanism of the positive inotropic effect evoked by dopamine. The dose-response curve for dopamine was not affected by the antagonists pimozide (10(-6) M), yohimbine (10(-5) M) pindolol (3 x 10(-8) M) and phentolamine (10(-6) M) when these agents were given separately. Only t...

The postictal state is generally followed by antinociception. It is known that connections between the dorsal raphe nucleus, the periaqueductal gray matter, and the locus coeruleus, an important noradrenergic brainstem nucleus, are involved in the descending control of ascending nociceptive pathways. The aim of the present study was to determine whether noradrenergic mechanisms in the locus coe...

Purpose: The American Urological Association convened the Clinical Guidelines Panel on Erectile Dysfunction to analyze the literature regarding available methods for treating organic erectile dysfunction and to make practice recommendations based on the treatment outcomes data. Materials and Methods: The panel searched the MEDLINE data base for all articles from 1979 through 1994 on treatment o...

The stimulus effects of ibogaine were compared with those of yohimbine, an alpha 2-adrenoceptor antagonist, 2,5-dimethoxy-4-methylamphetamine (DOM), a 5-hydroxytryptamine2 (5-HT2) agonist, and lysergic acid diethylamide (LSD), a nonspecific 5-HT agonist. Rats were trained with either yohimbine (6 mg/kg), DOM (0.6 mg/kg), or LSD (0.1 mg/kg) vs. no treatment in a two-lever discrimination task. Te...

Platelets express the imidazoline (I)-receptor, I1 and I2, as well as the α2-adrenoceptor. Although dexmedetomidine, a selective α2-adrenoceptor agonist with some affinity for the I-receptor is expected to affect platelet function, the effects of dexmedetomidine on platelet functions remain unclear. In the present study, we investigated the effects of dexmedetomidine on human platelet functions...