Laterality in functional and metabolic state of the bulbectomised rat brain detected by ASL and ¹H MRS: A pilot study

Abstract

Objectives

Pilot study validating the animal model of depression – the bilateral olfactory bulbectomy in rats – by two nuclear magnetic resonance methods, indirectly detecting the metabolic state of the brain. Furthermore, the study focussed on potential differences in brain laterality.

Methods

Arterial spin labelling assessed cerebral brain flow in prefrontal, sensorimotor, and piriform cortices, nucleus accumbens, hippocampus, thalamus, circle of Willis, and whole brain. Proton magnetic resonance spectroscopy provided information about relative metabolite concentrations in the cortex and hippocampus.

Results

Arterial spin labelling found no differences in cerebral perfusion in the group comparison but revealed lateralisation in the thalamus of the control group and the sensorimotor cortex of the bulbectomized rats. Lower Cho/tCr and Cho/NAA levels were found in the right hippocampus in bulbectomized rats. The differences in lateralisation were shown in the hippocampus: mI/tCr in the control group, Cho/NAA, NAA/tCr, Tau/tCr in the model group, and in the cortex: NAA/tCr, mI/tCr in the control group.

Conclusion

Olfactory bulbectomy affects the neuronal and biochemical profile of the rat brain laterally and, as a model of depression, was validated by two nuclear magnetic resonance methods.

Keywords:

• Arterial spin labelling
• depression
• magnetic resonance spectroscopy
• olfactory bulbectomy
• rats

Acknowledgements

None.

Statement of interest

The authors declare that the research was conducted without any commercial or financial relationships that could be construed as a potential conflict of interest.

Additional information

Funding

The animal preparation, behavioural testing, and behavioural results analysis were performed at Masaryk University as part of the project 'Behavioural psychopharmacology and pharmacokinetics in preclinical drug research,' number MUNI/A/1440/2021, with the support of the Specific University Research Grant, as provided by the Ministry of Education, Youth and Sports of the Czech Republic (MEYS) in the year 2022. The NMR measurement and data analysis were supported by the MEYS grants LM2015062 and CZ.02.1.01/0.0/0.0/18_046/00016045 'National Infrastructure for Biological and Medical Imaging (Czech-BioImaging).'