Researcher biography

Regulation of Transmitter Release Efficacy: Structural and Molecular Factors

Research in Dr Nickolas Lavidis' laboratory is focused on understanding the molecular basis for differences in the efficacy of transmitter release between release sites. Regulation of such molecular factors may be responsible for: (a) memory, (b) tolerance and withdrawal from opiates and some antihypertensives, and (c) hibernation.

The regulatory factors under investigation in the laboratory are:

  • Fluctuations in the calcium concentration within nerve terminals during rest
  • Density of voltage gated calcium channels at release sites
  • Density and proximity of terminal release sites to the target
  • Levels of vesicular associated proteins within terminal release sites
  • Density of postsynaptic receptors on the target
  • Neurotrophins which are known to be released by the target (nerve growth factor and neurotrophin-3)

The methods used in the laboratory are:

  • Visualisation of living nerve terminal release sites
  • Electrophysiological recording transmitter release from single/visualised release sites
  • Ultrastructure reconstruction of release sites using transmission electron microscopy
  • Immunohistochemistry using antibodies
  • Tissue culture of explants and single cells
  • Whole animal telemetry measurements of heart rate, temperature and locomotor activity

Significance: The nerve terminal is able to change and adapt to its environment by regulating its efficacy of neurotransmission. These studies are aimed at enhancing our understanding of what factors are being regulated and possibly responsible for adaptation.