|
|
|
Associate Professor David W Walker
NHMRC Principal Research Fellow
|
| Email: |
david.walker@med.monash.edu.au |
| Phone: |
+61 3 9905 2534 |
| Fax: |
+61 3 9905 2547 |
| Mail: |
Department of Physiology |
| |
Building 13f |
| |
Monash University |
| |
Victoria 3800 |
| |
Australia |
Research Interests and Expertise
Contributions to the discipline
David Walker’s research has presented important new information about development of the fetal brain and the autonomic nervous system, particularly in relation to emergence of sleep and behavioural states, circadian rhythms, and the regulation of the heart and cardiovascular system. His work began with investigation of the human heart and autonomic innervation, and then turned to investigation of the fetal sheep where important new information was provided on regulation of placental (maternal and fetal) blood flows, fetal endocrinology (especially hypothalamo-adrenal function), and the development of behaviour patterns and their control by a particular class of steroid compounds (neurosteroids). More recently, he introduced the spiny mouse into perinatal research, and the main focus of his research now is to use this species to answer some of the remaining big questions in reproduction and perinatal research, such as: what controls the length of gestation?; what prevents/causes preterm birth?; what are the causes of stillbirth and brain damage at birth?
Current research
Brain damage which occurs during pregnancy, or which evolves soon after birth may be subtle in resulting in learning disabilities and behavioural problems in children, or it may be catastrophic in that it results in outcomes such as epilepsy, spasticity, and cerebral palsy. David has recently established a research group to examine how the brain is damaged by events that disturb the pregnant woman’s health, the intrauterine environment, and the development of the fetal brain. The sole focus of their work now is to understand how the developing brain is damaged during pregnancy, or becomes vulnerable to damage by events that occur at birth or in the newborn period.
Cerebral palsy research group
David Walker recently established a research group to examine how the brain is damaged by events that disturb the in utero environment and fetal development. For these studies the group uses pregnant sheep, and a species new to this type of research, the Spiny Mouse (Acomys caharinus). The group’s Spiny mouse colony is the only one in Australia.
Results so far show that brief episodes of fetal asphyxia, or exposure to very low grades of infectious agents delivered directly to the placenta, are both sufficient to induce inflammation-like reactions in the fetal brain, and produce behavioural deficits in newborn lambs and Spiny mouse neonates. The group are now evaluating treatments that can be given to the pregnant animal to protect the fetal brain against these effects of asphyxia and infection. For example, they have shown that supplementing the mother’s diet with the essential nutrient creatine significantly improves survival of Spiny Mouse neonates and prevents the postnatal growth retardation that eventuates after birth asphyxia. In sheep, the group has shown that melatonin given to the pregnant ewe is able to prevent fetal brain damage caused by free radicals produced in response to intra-uterine asphyxia. These studies have direct relevance to human medicine, because such treatments could be given to women during pregnancy.
Current research grants
|
NHMRC Principal Research Fellowship
|
|
DW Walker (2007-2011)
|
NHMRC Project grants
|
|
Cerebrovascular Effects of Intrauterine Hypoxia: Contribution to Perinatal Brain Injury. M Castillo-Melendez, DW Walker. (2009 - 2011)
|
|
Preventing prenatal brain injury in fetal growth restriction. EM Wallace, SL Miller, G Jenkin, G Drummond, D Walker. (2009-2011)
|
|
Creatine synthesis and transport in fetal development. DW Walker, RD Snow, IR Young. (2007-2009)
|
|
The effects of maternal glucocorticoid administration in growth-restricted fetuses. EM Wallace, SL Miller, G Jenkin, DW Walker, H Parkington. (2007-2009)
|
|
Neurosteroid synthesis in perinatal brain - potential for neuroprotection of the developing brain. JJ Hirst, DW Walker. (2007-2009)
|
ARC Discovery project
|
|
Who determines length of gestation: mother or fetus? DW Walker, H Dickinson. (2009-2012)
|
Canadian Institutes for Health Research Project Grant
|
|
Studies on fetal alcohol syndrome in sheep. R Harding, DW Walker, A Bocking, J Brien. (2006-2007)
|
|
|
|
