University of Leicester
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Opioids and anaesthetic drugs as modulators of stimulus-secretion coupling.

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posted on 2015-11-19, 08:44 authored by Robert. Atcheson
The cellular mechanisms by which opioid and general anaesthetic drugs produce their clinical effect remain unclear, but modulation of stimulus-secretion coupling may be important. The human neuroblastoma cell line, SH-SY5Y, is a model of a human sympathetic neuron. The uptake and release (depolarization and receptor mediated) of [3H] noradrenaline ([3H] NA) in SH-SY5Y cells has been characterized, and the role of cAMP and calcium in evoked release examined. Further studies examined the effect of opioids (including fentanyl), a volatile anaesthetic agent (halothane), and intravenous anaesthetics (thiopentone and propofol) on uptake and release of [3H] NA. SH-SY5Y cells are capable of the uptake and evoked release of [3H] NA. K+ evoked release is dependent on extracellular calcium but carbachol evoked release appears to be extracellular calcium- independent. cAMP does not have a role in the immediate evoked release of [3H] NA, but an effect on long term secretion cannot be excluded. Fentanyl inhibits the uptake and release of [3H] NA, but this effect is not opiate receptor mediated. Morphine, DAMGO, met- and leu- enkephalin had no effect on [3H] NA release, and these results indicate that opiate receptors on SH-SY5Y cells are not coupled to neurotransmitter release. Halothane inhibits K+, but not carbachol evoked [3H] NA release. In addition, halothane inhibits [3H] NA uptake but only at relatively high concentrations. Thiopentone, but not propofol, inhibits [3H] NA uptake, and both drugs inhibit [3H] NA release. The results of these studies suggest that inhibition of voltage sensitive calcium channels by general anaesthetic agents may contribute significantly towards the state of anaesthesia.


Date of award


Author affiliation

Cell Physiology and Pharmacology

Awarding institution

University of Leicester

Qualification level

  • Doctoral

Qualification name

  • MD



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