Pharmacological and Biochemical Aspects of GABAergic Neurotransmission: Pathological and Neuropsychobiological Relationships

Beleboni, Renê Oliveira; Carolino, Ruither Oliveira Gomes; Pizzo, Andrea B.; Castellan-Baldan, Lissandra; Coutinho‐Netto, Joaquim; Santos, Wagner Ferreira dos; Coimbra, Norberto Cysne

doi:10.1007/s10571-004-6913-z

Cited by 66 publications

(43 citation statements)

References 203 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…As a first approximation, it appears that any increase in the accumulation of extracellular GABA would have a positive effect for the treatment of these afflictions (Beleboni et al, 2004;Conti et al, 2004;Yogeeswari et al, 2007).…”

Section: Resultsmentioning

confidence: 99%

“…The effect caused on GABA by secondary metabolites present in the different extracts tested, for example extracellular increase in its concentration, maybe due to modifying some of the processes involved in neurotransmission, such as the release, transport and/or removal of the neurotransmitter from the synaptic cleft (Conti et al, 2004;Beleboni et al, 2004). When analyzing the W. americana extracts of different polarity (C 6 H 14 , CH 2 CL 2 and MeOH) prepared from wild plant roots at a concentration of 10 µg/ml, no effect on the levels of GABA released was observed (data not shown).…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Methanolic extracts from roots and cell suspension cultures of Waltheria americana Linn induce GABA release in cerebral slices of mouse brain

Mundo¹,

Patricia²,

Maria³

et al. 2015

Afr. J. Pharm. Pharmacol.

View full text Add to dashboard Cite

This study evaluates and compares the release of the neurotransmitter γ-aminobutyric acid (GABA) induced by methanolic extracts obtained from roots of wild plants and from cell suspension cultures of W. americana Linn. The release of this neurotransmitter was evoked by crude and fractioned extracts derived from both roots of wild plant and cell suspension cultures, tested at three concentrations: 10, 50 and 100 µg/ml by means of in vitro incubation of slices of mouse cerebral cortex. Firstly, crude extracts from wild plant roots obtained by applying solvents of different polarities (n-hexane, dichloromethane and methanol) were tested at a concentration of 10 µg/ml with no observed effect on the level of GABA release, but when the same extracts at a concentration of 100 µg/ml was evaluated, methanol extract (MeOH) was determined to be the most effective in terms of the release of GABA . The results suggest that wild plant and cell suspension cultures of W. americana produce some compounds that cause an increase in the release of GABA in in vitro experiments, corroborating with the ethnomedical applications associated with this species, and indicates high potential for research and development of new active drugs for the treatment of several central nervous system (CNS) disorders related to the GABA system.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Methanolic extracts from roots and cell suspension cultures of Waltheria americana Linn induce GABA release in cerebral slices of mouse brain

Mundo¹,

Patricia²,

Maria³

et al. 2015

Afr. J. Pharm. Pharmacol.

View full text Add to dashboard Cite

show abstract

“…Activation of benzodiazepine receptors, which colocalise with GABA receptors, promotes inhibitory mechanisms in the brain. This protective effect is important from the point of view of the commencement and spread of excessive and synchronised neuronal discharge (Beleboni et al 2004). Midazolam can also inhibit glutamate release (Sakai and Amaha 2000) which can contribute to its anticonvulsant properties.…”

Section: Discussionmentioning

confidence: 99%

Influence of Midazolam and L-Arginine on Clinical Observations and Biochemical Changes in Rat Liver Induced by Pentylenetetrazole

et al. 2009

View full text Add to dashboard Cite

Certain types of convulsions may lead to multiorgan dysfunction. We investigated whether the chemoconvulsant pentylenetetrazole (PTZ) could influence energy synthesis in the liver besides evoking convulsions in adult male Wistar rats. In 80% of the rats PTZ (100 mg/kg body weight, administered intraperitoneally -i.p.) evoked generalised clonic convulsions (GCCs) and in 60% of the rats generalised clonic-tonic convulsions (GCTCs) within 4 min after its administration. Cytochrome c oxidase activity was simultaneously reduced approximately three-fold compared to 0.9% NaCl-treated (control) rats (p < 0.01). Midazolam administered before PTZ was an excellent anti-convulsant especially against GCCs (p < 0.05). However, it did not protect against the decrease in cytochrome c oxidase activity induced by PTZ. In contrast to midazolam, pretreatment with L-arginine did not prevent PTZ-evoked convulsions. However, it offered some protection against the PTZ-mediated reduction in cytochrome c oxidase activity. Our results open new avenues of research that will focus on the mechanisms of action of PTZ, midazolam and L-arginine with particular reference to their direct and/or indirect effects on liver function. Convulsions, cytochrome c oxidase, liver, midazolam, pentylenetetrazoleDespite years of studies the pathophysiological mechanisms underlying epilepsy are still not completely understood. In particular multiple questions remain to be answered, mainly relating to epileptic therapy which still faces a high failure rate. Several general anaesthetics and benzodiazepines that are regularly used in surgical practice are often administered for the treatment of epileptic seizures (Rossetti 2007;Holtkamp 2007;Riss et al. 2008). However, there are little published data concerning biochemical changes in organs apart from the brain, particularly during and after epileptic seizures (Akbas et al. 2005). In our current study emphasis was placed on determining changes in energy synthesis in the liver during convulsions and defining the effect of midazolam, a benzodiazepine commonly used in human and veterinary surgery, as well as the effect of L-arginine.Mitochondria are organelles whose main role is energy production. Accordingly, they are key components for determining cell survival. In contrast to smooth external membrane the inner mitochondrial membrane is wrinkled and forming crypts (cristae). As the number of crypts is directly proportional to the cell's energy demands, cells within the regions of the brain and liver tissue have the highest number of crypts.Important oxido-reductive processes occur in mitochondria which result in the synthesis of adenosine triphosphate (ATP). The latter is an energy-rich compound responsible for the vast majority of processes requiring a high energy transfer (Kakkar and Singh 2007).Reducing equivalents, such as NADH, are formed in the cytoplasm during glycolysis and are transported into mitochondria in order to assist the process of oxidative phosphorylation. The transfer of electrons from ...

show abstract

“…Spider venoms have been extensively studied for understanding the neurotoxic property [5][6][7]. Neurotoxins with varied potency have been isolated and studied [6,7].…”

Section: Introductionmentioning

confidence: 99%

“…Neurotoxins with varied potency have been isolated and studied [6,7]. Such neurotoxins are acylpolyamines, proteins, and peptides in nature.…”

Section: Introductionmentioning

confidence: 99%

Purification and Characterization of a Nonenzymatic Neurotoxin fromHippasa partita(Lycosidae) Spider Venom Gland Extract

Nagaraju

Kemparaju

2013

Journal of Toxins

View full text Add to dashboard Cite

India is a habitat for nearly one thousand four hundred forty-seven species of spiders under three hundred and sixty-five genera and sixty families. Our initial survey on toxic bite by spider revealed severe edema, itching, acute pain, and hemorrhage following tissue necrosis, which are the general symptoms of envenomation, but there are no reports of mortality. Significantly,Hippasa partitaspider, commonly called “funnel web spider,” which is endemic in hilly regions of the Western Ghats is responsible for envenomation. In this study, a nonenzymatic neurotoxin has been purified fromH. partitavenom gland extract. Gel filtration and ion exchange chromatography were used to purify the toxin into homogeneity as shown by SDS-PAGE, RP-HPLC, and MALDI-TOF. Neurotoxin is devoid of enzymatic activities but causes intense neurotoxic symptoms. Neurotoxin is found to inhibit the twitch response of sciatic nerve gastrocnemius muscle preparation and is found to be postsynaptic in action. Neurotoxin is devoid of coagulant activity, edema, and hemorrhage and is nonlethal to mice (up to 5 mg/kg body weight). In conclusion, a neurotoxin, which is a principle agent in whole venom responsible for induced neurotoxic symptoms, has been purified and characterized.

show abstract

Pharmacological and Biochemical Aspects of GABAergic Neurotransmission: Pathological and Neuropsychobiological Relationships

Cited by 66 publications

References 203 publications

Methanolic extracts from roots and cell suspension cultures of Waltheria americana Linn induce GABA release in cerebral slices of mouse brain

Methanolic extracts from roots and cell suspension cultures of Waltheria americana Linn induce GABA release in cerebral slices of mouse brain

Influence of Midazolam and L-Arginine on Clinical Observations and Biochemical Changes in Rat Liver Induced by Pentylenetetrazole

Purification and Characterization of a Nonenzymatic Neurotoxin fromHippasa partita(Lycosidae) Spider Venom Gland Extract

Contact Info

Product

Resources

About