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Updated: Jun 25, 2026
Recording and Modulation of Epileptiform Activity in Rodent Brain Slices Coupled to Microelectrode Arrays
Published on: May 15, 2018
MicroPET study of brain neuronal metabolism under electrical and mechanical stimulation of the rat tail
You-Yin Chen1, Yen-Yu I Shih, Chia-Nan Chien
1Department of Electrical and Control Engineering, National Chiao Tung University, Hsinchu City, Taiwan. irradiance@so-net.net.tw
Objective:
Small-animal positron emission tomography (microPET) has been widely used for measuring various molecular processes in the rodent brain. The somatotopic projection, however, has not been identified earlier using microPET under electrical stimulation (ES) and mechanical stimulation (MS). This study aimed to utilize microPET to investigate the glucose metabolism of cortical and thalamic responses to ES and MS of the rat tail.
Methods:
The rats were anesthetized by ketamine and a custom-built stereotaxic frame was used to fix the rat head to ensure that the scanned images were concordant with an atlas. [F]-fluorodeoxyglucose (FDG) was used as a radiotracer to reveal the brain metabolic changes. An activation index (AI) was calculated from microPET data o quantify the changes in local metabolic activities normalized to variations in FDG dosage between animals.
Results:
The results showed that ES increased FDG uptake in both the contralateral thalamus (AI=18) and cortex (AI=12.5), with significant side-to-side differences (P<0.05, paired t-test). MS also significantly increased FDG uptake in both cortical and thalamic regions, although lateralization was absent in the thalamus.
Conclusion:
This study indicated that microPET can be used to elucidate the functional and quantitative neuronal activities of brain structures of rodents under peripheral stimulation, and could be applied in investigations of brain sensory functions.
Insights
This study used microPET to map brain activity in rats responding to tail stimulation. Electrical and mechanical stimuli revealed increased glucose metabolism in the cortex and thalamus, demonstrating microPET
Area of Science:
- Neuroscience
- Molecular Imaging
- Physiology
Background:
- Small-animal positron emission tomography (microPET) is crucial for studying rodent brain molecular processes.
- Identifying somatotopic projections using microPET under electrical stimulation (ES) and mechanical stimulation (MS) remains an unexplored area.
- Understanding brain responses to peripheral stimuli is key to sensory function research.
Purpose of the Study:
- To employ microPET to investigate cortical and thalamic glucose metabolism in response to ES and MS of the rat tail.
- To quantify brain metabolic changes associated with peripheral sensory input.
- To explore the utility of microPET in mapping functional brain activity.
Main Methods:
- Rats were anesthetized and head-fixed in a stereotaxic frame for precise imaging.
- [18F]-fluorodeoxyglucose (FDG) was administered as a radiotracer to detect metabolic changes.
- An activation index (AI) quantified metabolic activity, normalized for FDG dosage variations.
Main Results:
- Electrical stimulation (ES) significantly increased FDG uptake in the contralateral thalamus (AI=18) and cortex (AI=12.5).
- Mechanical stimulation (MS) also elevated FDG uptake in cortical and thalamic regions, with absent lateralization in the thalamus.
- Significant side-to-side differences in metabolic activity were observed with ES (P<0.05).
Conclusions:
- MicroPET successfully elucidates functional and quantitative neuronal activities in rodent brain structures under peripheral stimulation.
- This technique provides a valuable tool for investigating brain sensory functions.
- The study demonstrates the potential of microPET in mapping somatotopic projections in response to tactile stimuli.
