Department of Cellular Neurophysiology
Laboratory of the Physiology of Calcium Signalling
The research focuses on: 1) the physiology of vasopressin and oxytocin signalling in neuron-glia interactions, injury, nociception, pregnancy and lactation in the central and peripheral nervous systems using newly developed transgenic rat models expressing an vasopressin-enhanced green fluorescent protein fusion gene and an oxytocin-enhanced cyan fluorescent protein fusion gene; 2) The physiology of the hypothalamo-neurohypophysial system and stimulus-secretion coupling in the neurohypophysis; and 3) The physiology of calcium signalling in human embryonic stem cell-derived neural precursors in the control of proliferation and differentiation and the identification of the molecular cascades of calcium signalling mechanisms and calcium homeostasis.
Confocal image of endogenous e-GFP fluorescence in freshly isolated neurohypophysis.
(A), dorsal root ganglia (DRG) explants (B) and freshly dissociated DRG neurons (DRG neurons after 48 h or 72 h culture – C, D). AVP e-GFP is spread uniformly throughout the cytoplasm of larger diameter neurons. Until 48 hours (C), when neurons start to project processes and form synapses, AVP e-GFP can also be observed in neurites and some neighboring glial cells. After 72 hours (D) in culture many glial cells, in addition to neurons, show e-GFP fluorescence.
Calcium traces from DRG neurons after 48 h cultivation.
DRG neurons are sensitive to vasopresin (AVP), K+ and capsaicin (A) and both oxytocin (OT , inset) and capsaicin.
Confocal image of freshly isolated neurohypophysis (NH) and DRG from OT e-CFP TG male.
(A, C) and lactating female (B, D) rats. The intensity of endogenous eCFP fluorescence in both the NH and DRG of lactating animals (B, D) is significantly higher than that seen in control male animals (A, C).
Confocal image of DRG neurons (48h culture).
Double immunostaining for oxytocin (red) and a neuronal marker – β-III tubulin (green). Neurons project long neurites and make connections with glial cells and each other. Endogenous e-CFP fluorescence is co-localized with OT staining and localized more densely in the nuclei of both neurons and glial cells.
Confocal image of DRG neurons (115h culture).
Endogenous e-CFP fluorescence, DAPI staining and immunostaining for NF-160. Cells positive for the neuronal marker NF160 project multiple long processes and connect with glial cells and each other. Endogenous e-CFP fluorescence can be visualized in both neuronal and glial cells.
