Research Article
Volume 12 Issue 8 - 2020
Mobilization of Intracellular Calcium by the General Anaesthetic Halothane in Cultured, Identified Molluscan Neurons
IA Ahmed1, PM Hopkins2,3 and W Winlow4,5,6*
1Faculty of Medicine, University of Garden City, Khartoum, Sudan
2Leeds Institute of Medical Research at St James’s, School of Medicine, University of Leeds, Leeds, United Kingdom
3Malignant Hyperthermia Investigation Unit, Leeds Institute of Molecular Medicine, St. James’s University Hospital, Leeds, United Kingdom
4Department of Biology, University of Naples Federico II, Via Cintia, Naples, Italy
5Institute of Ageing and Chronic Diseases, University of Liverpool, Liverpool, United Kingdom
6NPC Newton, Preston, United Kingdom
*Corresponding Author: W Winlow, Department of Biology, University of Naples Federico II, Via Cintia, Naples, Italy and Institute of Ageing and Chronic Diseases, University of Liverpool, Liverpool, United Kingdom and NPC Newton, Preston, United Kingdom.
Received: July 10, 2020; Published: July 22, 2020


  • The effects of clinical concentrations of halothane (2% and 4% halothane v/v) on the intracellular calcium concentration, [Ca2+]i, in four types of identified Lymnaea neurons in single cell culture were observed both in the presence and absence of extracellular calcium (zero Ca2+/EGTA).
  • Intracellular Ca2+ levels were measured with the cell-permeable ratiometric Ca2+ indicator Fura-2-acetoxymethyl ester (Fura-2 AM).
  • In the presence of external calcium there was a rapid increase in [Ca2+]i at both concentrations of halothane, which appeared to be both time and concentration dependent in all cell types. These effects were clearest in the neurons VV1 or 2 and RPD1.
  • Similar effects were observed in zero external calcium, but the clearest concentration dependency was in RPeD1, whose [Ca2+]i remained above control levels at washout, unlike those of the other neurons.
  • These data indicate that halothane causes release of calcium from internal stores, even in the absence of extracellular calcium.
  • We compare these findings with those from previous studies with caffeine and ryanodine, neither of which increased intracellular free calcium concentration in the absence of external calcium.

Keywords: Intracellular Calcium; Molluscan Neurons; Lymnaea Neurons


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Citation: W Winlow., et al. “Mobilization of Intracellular Calcium by the General Anaesthetic Halothane in Cultured, Identified Molluscan Neurons”. EC Neurology 12.8 (2020): 90-100.

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