Effects of monosialoganglioside on a new model of tardive dyskinesia

1- the effects of monosialoganglioside GM(1) were studied on a new model of tardive dyskinesia, i.e., the frequency of spontaneous tongue protrusions in rats repeatedly treated with reserpine.2- Rats were co-treated with vehicle (VEH) or reserpine (RES) (0.1 mg/kg, sc, every other day) and saline (SAL) or GM1 (5 mg/kg, ip, every day) for 30 days and observed for tongue protrusions on days 10, 20 and 30.3- During each test day animals of the RES+SAL, group exhibited an increase in tongue protrusions relative to rats of the VEH+SAL group. However, rats of the RES+GM(1) group showed an increased frequency of tongue protrusions only on day 10, when compared to animals of the VEH+SAL group. There were no significant differences in tongue protrusion frequency between the VEH+GM(1) and the VEH+SAL groups.4- These results differ from previous studies which reported a facilitatory effect of GM1 coadministration on conventional behavioral animal models of tardive dyskinesia: the possibility is raised that GM1 attenuates the reserpine-induced increase in tongue protrusions through its protective effect on glutamate/oxidative stress neurotoxicity.UNIV São Paulo,FAC MED VET,SCH VET MED,DEPT FARMACOL & TOXICOL APLICADA,BR-05508900 São Paulo,BRAZILUNIV FED PARANA,DEPT PHARMACOL,BR-80060000 CURITIBA,PARANA,BRAZILUniversidade Federal de São Paulo,DEPT PHARMACOL,São Paulo,BRAZILUniversidade Federal de São Paulo,DEPT PHARMACOL,São Paulo,BRAZILWeb of Scienc

Phosphatidylserine reverses reserpine-induced amnesia

The effects of phosphatidylserine (PS) were studied in rats treated with reserpine (1 mg/kg) immediately after training in the passive avoidance task. in experiment I, phosphatidylserine (25 mg/kg) was administered 30 min before or immediately after training. Acute pre- or post-treatment with phosphatidylserine was effective in reversing the amnestic effect of reserpine in test trials performed 24 h and 1 week after training. Experiment II was performed to determine if the long-term pretreatment with phosphatidylserine (25 mg/kg) for 7 days is able to protect the rats against the amnestic effects of reserpine in this task. the data show that phosphatidylserine reverses the impairment induced by reserpine in trials performed 74 h and 1 week after training. These results indicate that the memory deficits associated with catecholamine depletion caused by reserpine can be attenuated by acute pre- or post-training or by long-term pretreatment with this phospholipid. (C) 2000 Elsevier Science B.V. All rights reserved.Univ Fed Parana, Dept Pharmacol, Ctr Politecn, SNC,Lab Fisiol & Farmacol, BR-81531900 Curitiba, Parana, BrazilUniversidade Federal de São Paulo, Dept Psychobiol, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Psychobiol, São Paulo, BrazilWeb of Scienc

Behavioral effects of MK-801 on reserpine-treated mice

The effects of dizocilpine (MK-801), a noncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist, were studied on dopamine-related behaviors induced by reserpine treatments. This study focuses on behavioral syndromes that may used as models for Parkinson's disease, or tardive dyskinesia, and its response after glutamatergic blockage. Reserpine (1 mg/kg), administered once every other day for 4 days, produced increases in orofacial dyskinesia, tongue protrusion and vacuous chewing in mice, which are signs indicative of tardive dyskinesia. Reserpine also produced tremor and catalepsy, which are signs suggestive of Parkinson's disease. MK-801 (0.1 mg/kg), administered 30 min before the observation test, prevented the vacuous chewing movements., tongue protrusions and catalepsy induced by reserpine. However, MK-801 injection produced a significant increase of tremor in reserpine-treated mice. Reserpine (1 mg/kg), administered 90 min before the test and followed by apomophine injection (0.1 mg/kg) 5 min before the test, did not produce oral dyskinesia in mice. On the other hand, reserpine induced increases in tremor and catalepsy compared to control mice. MK-801 (0.1 mg/kg) administration attenuated the catalepsy and tremor induced by reserpine. Pretreatment with reserpine (1 mg/kg) 24 h before the observation test produced increases in vacuous chewing movements and tongue protrusion, as well as increases in tremor and catalepsy, whereas MK-801 (0.1 mg/kg) injection 90 min before the test reversed the effects of reserpine, These results show that reserpine produces different and abnormal movements, which are related to dose and schedule employed and can be considered as parkinsonian-like and tardive dsykinesia signs. the glutamatergic blockage produced by NMDA can restore these signs, such as vacuous chewing movements, tongue protrusions, catalepsy and tremor according to the employed model. (C) 2001 Elsevier Science Inc. All rights reserved.Univ Fed Parana, Dept Pharmacol, Ctr Politecn, SNC,Lab Fisiol & Farmacol, BR-81531990 Curitiba, Parana, BrazilUniversidade Federal de São Paulo, Dept Psychobiol, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Psychobiol, São Paulo, BrazilWeb of Scienc

Monosialoganglioside (GM(1)) attenuates the behavioural effects of longterm haloperidol administration in supersensitive rats

In the present study we investigated the effects of co-administration of GM(1) (15.0 mg/kg, twice daily, for 30 days) and haloperidol (1.0 mg/kg, twice daily, for 30 days), as well as the effects of a 5-day treatment with this dose of GM(1) after withdrawal from haloperidol in rats. the animals were evaluated in the open-field test and apomorphine-induced stereotyped behaviour. the results show that GM(1) was able to attenuate dopaminergic supersensitivity evaluated by the locomotion frequency at 24 and 48 h after the withdrawal from haloperidol. On the other hand, rearing frequency was changed neither by haloperidol nor by GM(1). in haloperidol-treated rats immobility time differs from 30 min observation session in comparison with the following sessions after the withdrawal from neuroleptic. Apomorphine-induced stereotyped behaviour produced a significant increase in scores of haloperidol-withdrawn rats. GM(1) did not modify the haloperidol effects and did not change the dopamine receptor affinity to apomorphine 100 h from abrupt neuroleptic withdrawal. (C) 2003 Elsevier B.V./ECNP. All rights reserved.Univ Fed Parana, Sector Ciencias Biol, Dept Farmacol, BR-81531990 Curitiba, Parana, BrazilUniversidade Federal de São Paulo, Dept Pharmacol, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Psychobiol, São Paulo, BrazilUniv São Paulo, Sch Vet Med, Appl Pharmacol & Toxicol Lab, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Pharmacol, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Psychobiol, São Paulo, BrazilWeb of Scienc

Phosphatidylserine (BCPS) did not reverse the memory impairment associated to intranigral MPTP lesion in rats

Univ Fed Parana, BR-80060000 Curitiba, Parana, BrazilUniv São Paulo, Fac Odontol, BR-14049 Ribeirao Preto, BrazilUNIFESP, São Paulo, BrazilUEPG, Ciencas Famaceuticas, Ponta Grossa, BrazilUNIFESP, São Paulo, BrazilWeb of Scienc