Faculty of Medical and Health Sciences

Muscle cell function lab

About our research

Our research applies spectrofluorometric techniques to determine ionic fluxes associated with excitation-contraction coupling and contractile function in the heart. Studies are carried out on isolated cardiac muscle from consenting human patients undergoing routine surgery, and from animal models of heart disease. Functional measurements of intracellular calcium and force are combined with real time analysis of mitochondrial oxidative phosphorylation and reactive oxygen species production. Tissue and cells are also subjected to immuno-histological examination of key proteins using confocal microscopy.

  • Key themes in our research include:
  • Energy supply in diabetic heart disease
  • Mitochondrial calcium cycling
  • Right ventricular hypertrophy
  • Stretch regulation of the heart
  • Hypertrophic heart failure
Exchange proteins activated by cAMP (Epac)
Confocal images of human atrial tissue from non-diabetic (A) and diabetic (B) patients antibody labelled for Epac 2 (red) and ryanodine receptors (RyR, green) are shown with nuclei counter stained (blue). The rectangles show a magnified view of the dashed sections for each. Arrows point to Epac 2 antibody labelling in close proximity to RyR clusters, and to dense labelling close to the nucleus. (S. Kaur, unpublished data.)
Isolated cardiomyocytes from control and hypertrophic rat hearts
Confocal images of right ventricular cardiomyocytes from a healthy control (A) and a hypertrophic (B) rat heart. Cells are antibody labelled with a sarcolemma marker (caveolin-3, green) and a marker for the ryanodine receptors (RyR2, blue). Hypertrophic myocytes show ultrastructural alterations and t-tubule irregularity which impairs Ca2+ handling necessary for synchronised excitation-contraction coupling in the heart. (A. Krstic, unpublished data.)

Current projects

  • Exploration of mitochondrial dynamics in the contractile dysfunction of diabetic heart disease. FRDF (Principal Invistigator: Dr Marie Ward, Department of Physiology)
  • Exploration of Exchange proteins activated by cAMP (EPAC) signalling in human Type 2 Diabetic hearts. AMRF (Principal Invistigator: Dr Marie Ward, Department of Physiology)
  • The diabetic heart: the impact of mitochondrial function, on myocyte calcium cycling and contractility. Greenlane Research and Educational Fund (Principal Investigator: Professor Peter Ruygrok, ADHB)
  • Does energy deficiency compromise myofilament contractility in diabetes? HRC Explorer (Principal Investigator: Dr Kenneth Tran, Auckland Bioengineering Institute)
  • Refuelling the human heart: boosting cellular energy production to combat heart disease. NHF Fellowship (Principal Investigator: Dr Amelia Power, University of Auckland and University of Otago)
  • Bioenergetics of human heart failure. HRC Hercus Fellowship (Principal Investigator: Dr Kenneth Tran, Auckland Bioengineering Institute)

Team members and collaborators

Principal Investigator

Dr Marie-Louis Ward




Principal Investigator