Ontogenetic profile of ecto-ATPase activity in rat hippocampal and caudate nucleus synaptic plasma membrane fractions
A Banjac1, N Nedeljković, A Horvat
1Department of Molecular Biology and Endocrinology, Vinca Institute of Nuclear Sciences, Belgrade, Yugoslavia.
Insights
Ecto-enzyme ecto-ATPase activity and protein levels in rat brain regions change with age. These changes suggest ecto-ATPase plays roles in brain development and aging beyond ATP metabolism.
Area of Science:
- Neuroscience
- Biochemistry
Background:
- Ecto-adenosine triphosphate (ATP)ases are enzymes crucial for regulating extracellular ATP and adenosine levels.
- Understanding the ontogeny of ecto-ATPase activity and protein expression is vital for comprehending brain development and aging.
Purpose of the Study:
- To investigate the ontogenetic profile of ecto-ATPase activity and protein content in rat brain synaptic plasma membranes.
- To explore the potential roles of ecto-ATPase in brain development and aging.
Main Methods:
- Isolation of synaptic plasma membranes from the caudate nucleus and hippocampus of rats at various ages (15, 30, 90, 180, 365 days).
- Assay of ecto-ATPase activity.
- Quantification of ecto-ATPase protein abundance using established methods.
Main Results:
- Ecto-ATPase activity peaked at 30 and 365 days of age in both brain regions.
- Ecto-ATPase protein abundance was highest at 15 days after birth.
- A discrepancy was observed between enzyme activity and protein levels during ontogeny.
Conclusions:
- The ontogenetic profile of ecto-ATPase suggests dynamic regulation during brain development and aging.
- Observed discrepancies between activity and abundance may indicate additional functions of ecto-ATPase beyond ATP hydrolysis.
- Ecto-ATPase likely plays a significant role in regulating synaptic cleft concentrations of ATP and adenosine, impacting brain development and aging processes.
Abstract:
An ontogenetic study of ecto-ATPase activity and the content of enzyme proteins was assessed in the caudate nucleus and hippocampal synaptic plasma membranes isolated from rats at various ages (15, 30, 90, 180 and 365 days). The ontogenetic profile revealed that the enzyme activities in both brain areas were the highest on day 30 and 365, while the ecto-ATPase protein abundance was the highest on day 15 after birth. Possible explanation for obtained ontogenetic profile and the discrepancy between activity and abundance may reside in the fact that ecto-ATPase during development could exert additional roles other than those related to metabolism of ATP. It is likely that ecto-ATPase, regulating the concentration of ATP and adenosine in synaptic cleft, has important role in the processes of brain development and aging.
