The long-term goal of this project is to understand fundamental molecular mechanisms by which lead mediates increased neurotransmitter release. Several lines of evidence support the thesis that lead interferes with the coordinated regulation of synaptic loading, vesicular movement, docking and fusion with presynaptic membranes. Recent biochemical data, employing in the vivo and in the vitro models, provides compelling evidence implicating lead-mediated perturbation of normal vesicular trafficking processes resulting in the inappropriate release of neurotransmitters in the neuromuscular in the inappropriate release of neurotransmitters in the neuromuscular junction, synaptosomes and in the permeabilized cell cultures. Preliminary data obtained in the response to previous review further strengthens the principal investigator's assertion that the effects of lead on ephaptic synaptic release of neurotransmitters may be mediated by binding to the regulatory protein synaptotagmin. However, the exact mechanism(s) of lead-induced spontaneous neurotransmitter release remain to be determined. The hypothesis that lead binds to synaptotagmin and, therefore, stimulates unscheduled release of neurotransmitters is addressed by three specific aims. Proposed experiments are aimed at understanding (1) the pharmacology of lead- binding to the calcium-dependent regulatory protein, synaptotagmin; (2) the role of lead-synaptotagmin complexes in the unscheduled neurotransmitter release; and (3) the alteration of lead-effects on proposed in the this revised submission may provide new insights into the role of lead in the perturbation of normal synaptic vesicular function.

Agency
National Institute of Health (NIH)
Institute
National Institute of Environmental Health Sciences (NIEHS)
Type
Research Program Projects (P01)
Project #
5P01ES008131-03
Application #
6301548
Study Section
Project Start
2000-04-01
Project End
2001-03-31
Budget Start
1998-10-01
Budget End
1999-09-30
Support Year
3
Fiscal Year
2000
Total Cost
$155,404
Indirect Cost
Name
Hugo W. Moser Research Institute Kennedy Krieger
Department
Type
DUNS #
167202410
City
Baltimore
State
MD
Country
United States
Zip Code
21205
Cheong, Jae Hoon; Bannon, Desmond; Olivi, Luisa et al. (2004) Different mechanisms mediate uptake of lead in a rat astroglial cell line. Toxicol Sci 77:334-40
Hossain, Mir Ahamed; Russell, Juliet C; Miknyoczki, Sheila et al. (2004) Vascular endothelial growth factor mediates vasogenic edema in acute lead encephalopathy. Ann Neurol 55:660-7
Patra, Ramesh C; Blue, Mary E; Johnston, Michael V et al. (2004) Activity-dependent expression of Egr1 mRNA in somatosensory cortex of developing rats. J Neurosci Res 78:235-44
Johnston, Michael V (2004) Clinical disorders of brain plasticity. Brain Dev 26:73-80
Johnston, Michael V (2003) Injury and plasticity in the developing brain. Exp Neurol 184 Suppl 1:S37-41
Bannon, Desmond I; Abounader, Roger; Lees, Peter S J et al. (2003) Effect of DMT1 knockdown on iron, cadmium, and lead uptake in Caco-2 cells. Am J Physiol Cell Physiol 284:C44-50
Glenn, Barbara S; Stewart, Walter F; Links, Jonathan M et al. (2003) The longitudinal association of lead with blood pressure. Epidemiology 14:30-6
Olivi, Luisa; Sisk, Jeanne; Bressler, Joseph (2003) The involvement of lipid activators of protein kinase C in the induction of ZIF268 in PC12 cells exposed to lead. Neurochem Res 28:65-71
Donovan, Stacy L; Mamounas, Laura A; Andrews, Anne M et al. (2002) GAP-43 is critical for normal development of the serotonergic innervation in forebrain. J Neurosci 22:3543-52
Kim, Kyung-Ah; Chakraborti, Tamal; Goldstein, Gary et al. (2002) Exposure to lead elevates induction of zif268 and Arc mRNA in rats after electroconvulsive shock: the involvement of protein kinase C. J Neurosci Res 69:268-77

Showing the most recent 10 out of 21 publications