Extensive postmortem stability of RNA from rat and human brain

Area of Science:

• Neuroscience
• Molecular Biology
• Genetics

Background:

• Postmortem RNA stability is crucial for molecular studies of the brain.
• Previous research has yielded conflicting results regarding RNA integrity after death.

Purpose of the Study:

• To assess the postmortem stability of brain RNA in both rat and human samples.
• To determine the impact of postmortem interval on RNA quantity and quality.

Main Methods:

• Collected rat brains at various postmortem intervals (0-48 hr) and human brain samples (7-36 hr).
• Measured RNA yield (quantity) and integrity (quality) using RNA gel blot hybridization and in vitro translation assays.
• Compared postmortem samples with fresh, unfrozen controls.

Main Results:

• Total RNA yields remained consistent across all postmortem intervals in rats.
• Rat brain mRNA showed no degradation, and in vitro translation products were unaffected by postmortem time.
• Human cortical RNA exhibited slight degradation, but this was not correlated with the postmortem interval.
• Human RNA translation showed slightly reduced incorporation at longer postmortem intervals, but high molecular weight peptides were consistently produced.

Conclusions:

• Brain RNA demonstrates extensive stability postmortem, even up to 48 hours.
• This stability supports the application of molecular genetic techniques for investigating human neurodegenerative diseases.
• The findings encourage the use of postmortem brain tissue for genetic research.