Project Details


In light of the importance of the calcium ion in neuronal function, the
object of this proposal is, first of all, to obtain a better understanding
of the control of intraneuronal calcium by studying the functional
significance of the 28,000 Mr brain calcium binding protein (calbindin).
The calbindin protein will be introduced into single cells using a patch
pipette and we will determine possible effects on intracellular calcium and
changes in calcium channel activity. Using CA1 hippocampal cells we will
also determine whether the presence of calbindin can protect against cell
death which results after exposure to high levels of glutamate and
subsequent excessive increase in intracellular calcium. In addition, we
will transfect PC12 cells with the calbindin gene and we will determine if
the presence of calbindin has an effect on neurite outgrowth which occurs
in response to nerve growth factor (NGF). If changes are observed, studies
using site directed mutagenesis will allow the elucidation of
structure-function relationships. We also propose to study the regulation
of calbindin in cultured, dissociated neurons. Preliminary findings
concerning an induction of calbindin by NGF in a dispersed culture of rat
cerebellar cells will be further investigated. In addition, we will examine
the possibility of regulation of calbindin expression by calcium. Our
second objective will be to determine whether there are alterations in
other calcium related genes, such as calcium calmodulin dependent protein
kinase (CaM kinase II), with seizure activity. Changes in CaM kinase II
gene expression will be examined in hippocampus, cortex and subcortical
structures (including amygdala, substantia nigra and striatum) of
commissure and amygdaloid kindled rats. In addition, changes in CaM kinase
II gene expression will also be examined in these structures after
pentylenetetrazole induced seizures. Finally, in order to obtain the best
understanding of the molecular basis of epileptogenesis, we will determine
by differential hybridization which genes are altered at early times after
kindling induced seizures (1 hour or 24 hours) or 28 days after the last
kindled seizure. Changes in gene expression in hippocampus and substantia
nigra will be initially investigated. DNA sequences of clones obtained by
differential hybridization will be compared to known sequences. cDNAs of
genes altered either at early times or 28 days after the last kindled
seizure will be used to determine by Northern analysis whether changes in
these genes are also observed with chemically induced seizures. We also
propose to examine human brain tissue from epileptic patients for changes
in these genes. These studies should enable us to identify alterations in
specific genes involved in convulsive neuronal activity. It is likely from
these studies that important advances can be made concerning the molecular
level changes underlying epileptogenesis.
Effective start/end date1/1/902/28/95


  • Genetics
  • Molecular Biology


Explore the research topics touched on by this project. These labels are generated based on the underlying awards/grants. Together they form a unique fingerprint.