Pharmacology, biochemistry, and behavior
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Pharmacol. Biochem. Behav. · Sep 2011
Comparative StudyPharmacokinetic and pharmacodynamic interactions of valproate, phenytoin, phenobarbitone and carbamazepine with curcumin in experimental models of epilepsy in rats.
The present study investigates the interaction of curcumin with four antiepileptic drugs (AEDs) in male Wistar rats. In the first protocol, seizures were induced using pentylenetetrazole (PTZ) and valproate was injected intraperitoneally (i.p.) in therapeutic and sub-therapeutic doses 30min before PTZ administration. Curcumin was co-administered with sub-therapeutic dose of valproate 60min before PTZ injection. ⋯ Additionally, curcumin reversed the oxidative stress due to seizures. However, curcumin co-administration did not cause any significant alteration in the serum levels of the AEDs. The results thus suggest the potential of curcumin as an adjunct to these AEDs in epilepsy with the advantage of increasing the efficacy, reducing the dose and side effects of the AEDs.
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Pharmacol. Biochem. Behav. · Sep 2011
Comparative StudyOral tremor induced by galantamine in rats: a model of the parkinsonian side effects of cholinomimetics used to treat Alzheimer's disease.
Anticholinesterases are the most common treatment for Alzheimer's disease, and, in recent years, a new group of cholinesterase inhibitors (i.e. rivastigmine, galantamine, and donepezil) has become available. Although these drugs improve cognitive symptoms, they also can induce or exacerbate parkinsonian symptoms, including tremor. The present studies were conducted to determine if galantamine induces tremulous jaw movements, a rodent model of parkinsonian tremor, and to investigate whether these oral motor impairments can be reversed by co-administration of adenosine A(2A) antagonists. ⋯ P.) produced a dose dependent suppression of tremulous jaw movements induced by a 3.0 mg/kg dose of galantamine, indicating that galantamine induces these tremulous oral movements through actions on muscarinic acetylcholine receptors. In two additional studies, analyses of freeze-frame video and electromyographic activity recorded from the lateral temporalis muscle indicated that the local frequency of these galantamine-induced jaw movements occurs in the 3-7 Hz frequency range that is characteristic of parkinsonian tremor. In the final experiment, the adenosine A(2A) antagonist MSX-3 significantly attenuated the tremulous jaw movements induced by the 3.0mg/kg dose of galantamine, which is consistent with the hypothesis that co-administration of adenosine A(2A) antagonists may be beneficial in reducing parkinsonian motor impairments induced by anticholinesterase treatment.
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Pharmacol. Biochem. Behav. · Sep 2011
Comparative StudySubeffective doses of nitroparacetamol (NCX-701) enhance the antinociceptive activity of the α₂-adrenoceptor agonist medetomidine.
The α₂-adrenergic system is involved in pain processing and inflammation-induced sensitization. α₂-adrenoceptor agonists induce analgesia, and this effect is greater when administered in combination with other analgesics. In the present study, we assessed a possible enhancement of antinociception combining the α₂-adrenoceptor agonist medetomidine with subeffective doses of NCX701 (nitroparacetamol). ⋯ In addition, the duration of antinociception was significantly longer (P<0.001, 100 min after administration). The use of low doses of NCX701 and α₂-adrenoceptor agonists might open new perspectives in the treatment of inflammatory pain.