PubMed Health⌕ Search

Biomedical subjects

Shanthi N Pal

Publications and source records attributed to Shanthi N Pal.

6 recordsLinked to original sources

Thioperamide reduces intracellular calcium in mouse brain synaptosomes.

Intracellular calcium regulation is vital for cells, especially for neurons; raised levels are associated with cytotoxicity and neuronal death. In this report, we present the first experimental evidence showing a concentration-dependent reduction of free calcium in the mouse brain synaptosomes by thioperamide (THP), an H3 receptor antagonist. This is interesting in view of the recent reports on the anticonvulsant and cognition facilitating effects of THP. A neuroprotective potential of THP is suggested.

Analysis of Variance↗

Effects of folic acid and lamotrigine therapy in some rodent models of epilepsy and behaviour.

It has been suggested that a folic acid (FA) deficiency induced by antiepileptic drugs might be the basis for the neuropsychiatric toxicity associated with these drugs. In the present study, lamotrigine (LTG), one of the newer antiepileptic drugs, was evaluated for its effect on epilepsy, mood and memory in mice. Further, the effect of the addition of FA to LTG therapy was also investigated. The increasing current electroshock seizure test was used to evaluate the anticonvulsant effect of drugs, while the forced swimming test (FST) and spontaneous alternation behaviour (SAB) models were employed for assessing the effects on mood and memory, respectively. LTG exhibited a dose-dependent increase in seizure threshold, whereas FA did not have any effect. LTG did not affect, whereas FA decreased, behavioural depression in the FST in mice. Neither LTG nor FA affected memory scores in the SAB test. The combination of LTG and FA significantly reduced depression while enhancing the effects on memory and seizure threshold. The present observations have confirmed the antiepileptic action of LTG in yet another rodent model of epilepsy. Further, the results clearly demonstrate the additional benefits on epilepsy, mood and memory brought about by the inclusion of FA in the LTG regimen.

Animals↗

Competition between memory systems: acetylcholine release in the hippocampus correlates negatively with good performance on an amygdala-dependent task.

Lesions of the amygdala impair acquisition of a food conditioned place preference (CPP) task. In contrast, lesions of the fornix facilitate acquisition on this task, showing that an intact hippocampal system can interfere with learning an amygdala-dependent task. Our recent findings indicate that acetylcholine (ACh) release in the hippocampus increases while rats perform a hippocampus-dependent spontaneous alternation task. To the extent that ACh output in the hippocampus reflects activation of that brain area in learning and memory, the results obtained with fornix lesions suggest that ACh release in the hippocampus might be negatively correlated with learning on a CPP task. Using in vivo microdialysis, release of ACh was measured in the hippocampus while rats learned and were tested on an amygdala-dependent CPP task and a hippocampus-dependent spontaneous alternation task. Release of ACh in the hippocampus increased when rats were tested on either task. The magnitude of the increase in release of hippocampal ACh was negatively correlated with good performance on the amygdala-dependent CPP task. These findings suggest that ACh release may reflect activation and participation of the hippocampus in learning and memory, but in a manner that can be detrimental to performance on a task dependent on another brain area.

Acetylcholine↗

Effects of gabapentin and antidepressant drug combinations on convulsions and memory in mice.

In epileptic patients, neurobehavioral problems such as cognitive impairment, depression, and psychosocial impairments have been described, which may have a pathological and/or iatrogenic basis. For this reason additional treatment is required, beside antiepileptic drug (AED) therapy, to correct the accompanying neurological deficits. However, the rationale behind use of antidepressants along with antiepileptics has been questioned due to proconvulsant effects of the former. In the present study, the effect of gabapentin (GBP) on seizure score and memory is evaluated when it is given alone and in combination with some antidepressants, such as sertraline (SERTR) and alprazolam (ALP). Pentetrazole (PTZ)-induced convulsion and spontaneous alternation behavior (SAB) models were used to study the anticonvulsant effect and effect on memory, respectively. Results showed that addition of SERT to GBP or ALP resulted in reduction of anticonvulsant efficacy of these drugs. However, the combination of GBP + SERT + ALP was superior as far as effect on seizure severity and memory was concerned.

Acetates↗