Showing papers by "Flaminia Pavone published in 1999"
TL;DR: Five experiments were carried out to investigate opioid and NMDA receptor-mediated responses to one-trial inhibitory avoidance training in CD1 mice, and the potentiation of the impairing effect of MK-801 induced by immobilization stress was antagonized by naltrexone.
33 citations
TL;DR: The long-term effects of postnatal manipulation on nociception were studied in NMRI albino male mice in terms of involvement of the opioid system and of the characteristics of pup manipulation.
26 citations
TL;DR: The results demonstrate that irrespective of the way of its injection, the antinociceptive effect of oxotremorine is modulated by activity of the spinal NO, and further support the hypothesis that NO present in the spinal cord exerts pronociception effects.
15 citations
TL;DR: The results confirm, and extend to tonic pain, the analgesic effect exerted by oxotremorine on phasic responses, and indicate both spinal and supraspinal CNS sites of action.
8 citations
TL;DR: Results evidenced a role of cholinergic system in the modulation of tonic pain and in nitric oxide synthase expression at the spinal cord level, which further suggests that these two systems could be involved in phenomena induced by long-lasting nociceptive stimulation.
Abstract: The present research was undertaken to investigate, by behavioral and immunohistochemical methods, the effects of intrathecal (i.th.) injection of the muscarinic agonist oxotremorine on the response to the long-lasting nociceptive stimulus induced by injection of formalin into the rat hind paw. Formalin injection induced a biphasic, pain-induced behavioral response (paw jerks), as well as an increase in the number of nitric oxide (NO) synthase-labeled neurons in laminae I-III, IV, and X, but not in laminae V-VI. Oxotremorine (0.1-10 ng, i.th.) inhibited paw-jerk frequency in both phases of formalin-induced behavior. The immunohistochemical results showed that i.th.-injected oxotremorine differently affected the level of NO synthase in lumbar part of the spinal cord: no change or increase after the dose of 1 ng, and a significant reduction of nitric oxide synthase neurons after the higher dose (10 ng). These results evidenced a role of cholinergic system in the modulation of tonic pain and in nitric oxide synthase expression at the spinal cord level, which further suggests that these two systems could be involved in phenomena induced by long-lasting nociceptive stimulation.
7 citations
TL;DR: The results suggest that, in the case of concomitant administration, nimodipine could alleviate adverse side effects of tricyclic antidepressant, i.e., psychomotor disturbances.
Abstract: The effects of the dihydropyridine calcium channel blocker nimodipine on avoidance impairment induced by the tricyclic antidepressant amitriptyline were assessed during shuttle-box training and in previously trained mice of the DBA/2 strain. Nimodipine (0, 0.5, 1, 2.5, or 5 mg/kg) had no effect alone, but attenuated the avoidance impairment induced by 5 mg/kg amitriptyline on avoidance acquisition, as well as on a previously learned avoidance response. The avoidance improving action of the calcium channel blocker was less evident in mice receiving a larger dose (7.5 mg/kg) of the antidepressant drug. The effect of nimodipine did not appear to be specifically related to the avoidance impairment induced by amitriptyline, because the calcium antagonist also attenuated the avoidance impairing action of the neuroleptic chlorpromazine. The avoidance impairment induced by amitriptyline and chlorpromazine, and the related ameliorating action of nimodipine, seem imputable to drug effects on the performance of the avoidance response, rather than to interferences with learning processes. The results suggest that, in the case of concomitant administration, nimodipine could alleviate adverse side effects of tricyclic antidepressant, i.e., psychomotor disturbances.
7 citations
TL;DR: The acetylcholinesterase reversible inhibitor N-octyl-1,2,3, 4-tetrahydro-9-aminoacridine (THA-C8) is a new synthesized derivative of tacrine characterized by an alkyl chain in the molecular structure which ameliorates the penetrability of the compound into the central nervous system.
4 citations
TL;DR: Results indicate that glucose may exert an inhibitory action even on the central action of combinations of opiate and antihistaminic agents, drug combinations able to produce additive euphoric effects in humans.
Abstract: The present study examined the effects of glucose on the hyperactivity induced by morphine (10 mg/kg), given alone or combined with the histamine H1-receptor antagonist tripelennamine (2.5 or 5 mg/kg), in mice of the CD-1 strain. In the first experiment, glucose (50, 100, 250, or 500 mg/kg) had no significant effect on spontaneous locomotor activity, but at the dose of 100 mg/kg significantly reduced morphine-induced hyperactivity. In the second experiment, the administration of glucose (50 or 100 mg/kg) was also able to attenuate the locomotor stimulation induced by combined tripelennamine and morphine. The results are consistent with the hypothesis that glucose may inhibit opiate functions and indicate that glucose may exert an inhibitory action even on the central action of combinations of opiate and antihistaminic agents, drug combinations able to produce additive euphoric effects in humans.
1 citations