Vlado Buljan

•

William Lin

•

Guo Jun Liu

Dr Vlado Buljan - Postdoctoral Research Fellow

THE ROLE OF SPINAL CORD ASTROCYTES IN NEUROPATHOLOGICAL PAIN

Recent studies of extraterritorial and mirror image pain, have led to new insights concerning a crucial role of a spinal cord astrocytes in creation and maintenance of these pathological pain states [Watkins, 2002].

Figure 1 - Confocal microscopy of neurons (bigger) and glia (smaller) cells in spinal cord slice, 120µm thickness, labeled with calcium sensitive dye Fluo-3, AM. (V. Buljan & W. Lin)

Particularly, in dorsal horn, astrocytes were always dramatically activated in response to diverse axonal lesions that create exaggerated pain [Colburn, 1999]. Usually, their volume is enlarged two-three times and their number is increased.

We are studying spinal cord astrocyte- astrocyte, and astrocyte-neuron communication through calcium wave propagation using chemical, mechanical and electrical stimuli.

 
Figure 2 - Extended Configuration of
Astrocytes on Nylon Thread

References

1. Watkins LR, & Maier SF. Beyond neurons: Evidence That Immune and Glial Cells Contribute to Pathological pain States. Physiol Rev 82: 981-1011, 2002.

2. Colburn RW, Rickman AJ, & DeLeo JA. The Effect of Site and Type of Nerve Injury on Spinal Glial Activation and Neuropathic Pain Behavior. Exp Neurol 157: 289-304, 1999.
   

Dr William Lin - Senior Research Officer

Glial cells have been documented to play only supportive roles in the nervous system, however recent studies demonstrated that the glial cells actively engage in the signal transduction. Thus, my current research is focusing on the signal propagation in glial cells both in central nervous system (CNS) and peripheral nervous system (PNS), and interaction (cross talk) with neurons. I am trying to identify the neurotransmitters (substances) that mediate the signal propagation and interaction.

Recent publications

1. Liu GJ, Simpson AM, Swan MA, Tao C, Tuch BE, Crawford RM, Jovanovic A, Martin DK, (2003). ATP-sensitive Potassium Channels Induced in Liver Cells after Transfection with Insulin cDNA and the GLUT2 Transporter Regulate Glucose-stimulated Insulin Secretion. FASEB Journal. in press

2. Liu GJ, Martin DK, Gardner RC and Ryan PR, (2002), Large Mg2+-dependent currents are associated with the increased expression of ALR1 in Saccharomyces cerevisiae FEMS Microbiology Letters, 213:231-237.
   

Dr Guo Jun Liu - Senior Research Officer

Glial cells have been documented to play only supportive roles in the nervous system, however recent studies demonstrated that the glial cells actively engage in signal transduction. My current research is focusing on the signal propagation in glial cells in central nervous system (CNS) and interaction (cross talk) with neurons. I am trying to identify the neurotransmitters (substances) that mediate the signal propagation and interaction.

One of my recent results is shown in the following figure. Autaptic currents were recorded from a single hippocampus neuron grown on a micro-island with several astrocytes, which were facilitated by the ATP analogue, UTP.

Figure 1

Recent selected publications

1. 1. Liu GJ and Bennett MR, (2003). ATP secretion from nerve trunks and Schwann cells mediated by glutamate, NeuroReport, in press
   
   
2. Liu GJ, Abdipranoto A, Werry EL, Bennett MR, (2003). Mechanisms of secretion of ATP from cortical astrocytes triggered by uridine triphosphate. NeuroReport, in press.
   
   
3. Liu GJ, Simpson AM, Swan MA, Tao C, Tuch BE, Crawford RM, Jovanovic A, Martin DK, (2003). ATP-sensitive Potassium Channels Induced in Liver Cells after Transfection with Insulin cDNA and the GLUT2 Transporter Regulate Glucose-stimulated Insulin Secretion. FASEB Journal, express article 10.1096/fj.02-0051fje.
   
   
4. Liu GJ, Martin DK, Gardner RC and Ryan PR, (2002), Large Mg2+-dependent currents are associated with the increased expression of ALR1 in Saccharomyces cerevisiae FEMS Microbiology Letters, 213:231-237.