Glutamate-mediated influx of extracellular Ca2+is coupled with reactive oxygen species generation in cultured hippocampal neurons but not in astrocytes

2004 ◽  
Vol 79 (1-2) ◽  
pp. 262-271 ◽  
Author(s):  
Stefan Kahlert ◽  
Gregor Zündorf ◽  
Georg Reiser
2015 ◽  
Vol 4 (6) ◽  
pp. 1613-1622 ◽  
Author(s):  
Tianshu Wu ◽  
Keyu He ◽  
Qinglin Zhan ◽  
Shengjun Ang ◽  
Jiali Ying ◽  
...  

CdTe QD exposure caused death and apoptosis of rat primary cultured hippocampal neurons via generating reactive oxygen species and increasing intracellular calcium levels, which could be reversed by a common antioxidant NAC.


2018 ◽  
Vol 128 (3) ◽  
pp. 539-554 ◽  
Author(s):  
Yuan Xing ◽  
Nan Zhang ◽  
Wei Zhang ◽  
Lei-Ming Ren

Abstract Background Bupivacaine induces central neurotoxicity at lower blood concentrations than cardiovascular toxicity. However, central sensitivity to bupivacaine is poorly understood. The toxicity mechanism might be related to glutamate-induced excitotoxicity in hippocampal cells. Methods The intracellular free Ca2+ concentration ([Ca2+]i), mitochondrial membrane potential, and reactive oxygen species generation were measured by fluorescence and two-photon laser scanning microscopy in fetal rat hippocampal neurons and astrocytes. Results In astrocyte/neuron cocultures, 300 μM bupivacaine inhibited glutamate-induced increases in [Ca2+]i in astrocytes by 40% (P < 0.0001; n = 20) but significantly potentiated glutamate-induced increases in [Ca2+]i in neurons by 102% (P = 0.0007; n = 10). Ropivacaine produced concentration-dependent effects similar to bupivacaine (0.3 to 300 μM). Tetrodotoxin did not mimic bupivacaine’s effects. In pure cell cultures, bupivacaine did not affect glutamate-induced increases in [Ca2+]i in neurons but did inhibit increased [Ca2+]i in astrocytes. Moreover, bupivacaine produced a 61% decrease in the mitochondrial membrane potential (n = 20) and a 130% increase in reactive oxygen species generation (n = 15) in astrocytes. Cyclosporin A treatment suppressed bupivacaine’s effects on [Ca2+]i, mitochondrial membrane potential, and reactive oxygen species generation. When astrocyte/neuron cocultures were incubated with 500 μM dihydrokainic acid (a specific glutamate transporter–1 inhibitor), bupivacaine did not potentiate glutamate-induced increases in [Ca2+]i in neurons but still inhibited glutamate-induced increases in [Ca2+]i in astrocytes. Conclusions In primary rat hippocampal astrocyte and neuron cocultures, clinically relevant concentrations of bupivacaine selectively impair astrocytic mitochondrial function, thereby suppressing glutamate uptake, which indirectly potentiates glutamate-induced increases in [Ca2+]i in neurons.


The eff ect of the non-opiate analog of leu-enkephalin (peptide NALE: Phe – D – Ala – Gly – Phe – Leu – Arg) on the reactive oxygen species generation in the heart of albino rats in the early postnatal period was studied. Peptide NALE was administered intraperitoneally in the dose of 100 μ/kg daily from 2 to 6 days of life. Reactive oxygen species generation was assessed by chemiluminescence in the heart homogenates of 7-day-old animals. Decreasing of reactive oxygen species generation nearly by 30 % and an increasing in antioxidant system activity by the 20-27 %, compared with the control parameters, were found. The antioxidant eff ect of peptide NALE is associated with the presence of the amino acid Arg in the structure of the peptide. An analogue of NALE peptide, devoid of Arg (peptide Phe – D – Ala – Gly – Phe – Leu – Gly), had a signifi cant lower antioxidant eff ect. The NO-synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME) in the dose 50 mg/kg, administered with NALE peptide, reduced the severity of the NALE antioxidant eff ect. The results of the study suggest that the pronounced antioxidant eff ect of NALE peptide in the heart of albino rats, at least in part, is due to the interaction with the nitric oxide system.


1993 ◽  
Vol 149 (1) ◽  
pp. 64-67 ◽  
Author(s):  
Donald L. Weese ◽  
Michael L. Peaster ◽  
Kyle K. Himsl ◽  
Gary E. Leach ◽  
Pramod M. Lad ◽  
...  

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