Amino acid transport by synaptosomes isolated from post mortem human brain

Area of Science:

• Neuroscience
• Biochemistry

Background:

• Synaptosomes, nerve terminal preparations, are vital for studying neurotransmitter release.
• Investigating post mortem brain tissue presents challenges in maintaining cellular function.

Purpose of the Study:

• To assess the viability of post mortem human brain synaptosomes for studying neurotransmitter release.
• To establish a reliable method for detecting alterations in amino acid transport systems.

Main Methods:

• Isolation of synaptosomes from post mortem human brain tissue.
• Measurement of depolarisation-induced release of transmitter amino acids.
• Assessment of oxygen uptake as a marker of synaptosome viability.

Main Results:

• Active synaptosome preparations remained viable for up to 24 hours post mortem.
• Depolarisation-induced amino acid release showed a positive correlation with oxygen uptake rates.
• This correlation is essential for interpreting changes in amino acid transport.

Conclusions:

• Post mortem human brain synaptosomes can be actively prepared for up to 24 hours.
• Oxygen uptake is a critical parameter to consider when assessing amino acid release and transport.
• Accounting for oxygen uptake is necessary to identify disease-specific alterations in presynaptic amino acid transport.