Descending control of pain pathways [ 2007 - 2008 ]

Research Grant

Researchers: Prof Robert Callister (Principal investigator) ,  Prof Alan Brichta ,  Prof Trevor Day

Brief description Current treatments for chronic pain are limited in their success. This emphasises the need for new insights into the basic mechanisms and nervous system circuitry underlying altered or chronic pain states. Work in animals and patients with chronic pain shows that certain brainstem centres communicate, via descending spinal cord pathways, with small nerve cells in the superficial dorsal horn (SDH) of the spinal cord. These SDH neurones receive and process pain-signalling information from the skin and internal organs, and receive inputs from descending pathways. This descending input can either inhibit or enhance the activity of SDH neurones and subsequent pain perception. Till now it has been difficult to directly examine how descending pain pathways influence the small SDH neurones in the spinal cord. A new approach, which has been developed in our laboratory, now allows us to record from these very small SDH neurones in the spinal cord of an intact deeply anaesthetized mouse. In addition, our technique allows us to examine the recorded SDH neurone s responses to functionally relevant stimuli (brushing or pinching the hindpaw) as well as its physiology and anatomy. This project will use our new techniques to examine the effects of activating descending brainstem pathways that alter the way painful stimuli are processed in the spinal cord. The effects of altered levels of inhibition in the spinal cord will also be studied by using mice with naturally occurring mutations in their inhibitory glycine receptors. We believe a more complete understanding of pain processing mechanisms will be achieved by examining the role of descending pathways in an intact animal preparation. Such data are essential for the development of drug therapies that can successfully target pain syndromes.

Funding Amount $AUD 441,473.43

Funding Scheme NHMRC Project Grants

Notes Standard Project Grant