Isoflurane affects brain functional connectivity in rats 1 month after exposure

Area of Science:

• Neuroscience
• Anesthesiology
• Molecular Biology

Background:

• Isoflurane is a common preclinical anesthetic.
• Anesthesia can induce brain plasticity and long-term molecular changes.
• These changes may affect brain network function and cognition.

Purpose of the Study:

• To investigate the long-term effects of a single isoflurane exposure on brain function and gene expression.
• To understand the mechanisms behind isoflurane-induced brain plasticity.

Main Methods:

• Male Wistar rats were exposed to 1.8% isoflurane for 3 hours.
• Resting-state functional MRI (fMRI) and local field potential (LFP) measurements assessed functional connectivity after 1 month.
• Whole genome mRNA sequencing analyzed gene expression in cortical and hippocampal tissues.

Main Results:

• Isoflurane exposure strengthened thalamo-cortical and hippocampal-cortical functional connectivity.
• Increased low-frequency fMRI power in the cortex and enhanced hippocampal-cortical alpha and beta coherence were observed.
• Altered expression of 20 cortical genes involved in neuronal signaling was detected, with no hippocampal gene expression changes.

Conclusions:

• A single isoflurane exposure induces prolonged changes in brain connectivity and cortical gene expression related to neuronal signaling.
• These findings highlight potential mechanisms for long-term neurological consequences of anesthesia.
• Further research is needed to correlate these changes with postoperative behavioral and cognitive symptoms.