- Email: [email protected]
Neuromodulation of prefrontal background oscillatory activities with high-frequency repetitive transcranial magnetic stimulation
Abstracts / Neuroscience Research 71S (2011) e108–e415
P4-v03 Establishment of new approaches to understanding the brain glycogen metabolism—By NMR spectroscopic technique using 13 C-labeled glucose and lactate Hirokazu Mizokawa Tomoyuki Kanamatsu
, George
Kokubu, Youichi
Kobayashi,
Department of Environmental Engineering for Symbiosis, Faculty of Engineering, Soka University, Tokyo, Japan It has been reported that the concentration of glycogen in brain is one tenth of that in liver and the localized-distribution of glycogen is found only in astrocytes. Magistretti et al. reported that one possible neuro-protective mechanism of glial glycogen might be to provide lactate as fuel for neurons. However, the physiological function and metabolic role of brain glycogen are still unclear. Due to postmortem degradation, it is difficult to determine the concentration of brain glycogen and lactate. So, we established a new approach to know the brain glycogen metabolism. After 24 h starvation, the rat were raised only [1–13 C]-glucose solution (10%, w/v) for 6, 12, 24 h, and then collect blood under anesthesia and sacrificed by microwave treatment (5.0 kW, 1.2 s) to the head. The brain, liver and blood was homogenized with 6% PCA and divided into two portions respectively. One portion was used for glucose assay. The other portion was added NaBH4 to change the NMR chemical shift of glucose, and then incubated for 16 h after adding amyloglucosidase for measuring the glycogen concentration. 1 H NMR shows the fractional enrichment (FE) of glucose and lactate (which indicates the % of glucose used for synthesis glycogen and lactate). 13 C NMR also shows the amount of 13 C incorporated into glycogen and lactate from [1–13 C]-glucose. The blood glucose level was almost normal from 6 to 24 h after the onset of [1–13 C]-glucose solution and the values of FE of blood glucose and lactate was about 80% and 35%, respectably. The FE of glucose and lactate in the brain was also detected by 1 H NMR. These methods for knowing the metabolism of glucose, lactate and glycogen may be useful for understanding the brain energy metabolism.
e413
P4-v05 The selective injection system into hippocampus CA1 utilizing theta oscillation Kogo Takamiya , Jyoji Tsutajima, Takato Kunitake Dep. of Integrative Physiology, Faculty of Med., Unv. of Miyazaki, Miyazaki, Japan Hippocampus CA1 has been intensively studied due to its important roles in synaptic plasticity underlying learning/memory. In particular, much effort has been devoted to clarify its molecular mechanism of in vitro synaptic plasticity paradigm, LTP (long-term potentiation). Hippocampus CA1 LTP has been studied using acute brain slices. In contrast, it is difficult to mimic LTP in dissociated cultured neurons, suggesting that hippocampus LTP is expressed by unknown mechanisms including a network connection. In addition, several different forms of synaptic plasticity are reported in various brain regions and ages, presumably expressed in individual mechanisms. These complicated natures of LTP provoke difficulty in creating a detailed analysis of the molecular mechanism. One approach to this study is directly injecting viruses expressing cDNA/shRNA into hippocampus CA1 and analyzing neuronal functions in normal neuronal circuitry. In general, virus is injected via pipette that is inserted from the top of the brain cortex. However, by this approach, it is difficult to locate CA1 accurately using a pipette, since CA1 pyramidal cell layer is only 0.2 mm in width. In the present study, we have established a system to accurately introduce viral vectors in the stereotactic injection system into mouse hippocampus CA1 by monitoring theta oscillation. We decided the correct depth of the pipette tip based on the integrated values of theta oscillation at each depth. This approach allows us to inject virus accurately and provide an efficient method to transfer genes into hippocampus CA1 neurons, in the studies of molecular mechanisms of synaptic plasticity and other neuronal functions. Research fund: The Naito Foundation Natural Science Scholarship, Uehara Memorial Foundation, KAKENHI 22300122. doi:10.1016/j.neures.2011.07.1810
doi:10.1016/j.neures.2011.07.1808
P4-v04 Neuromodulation of prefrontal background oscillatory activities with high-frequency repetitive transcranial magnetic stimulation Yoshihiro Noda 1 , Motoaki Nakamura 1 , Takashi Saeki 1 , Hideo Iwanari 1 , Kiyoto Kasai 2 1
Kinko Hospital, Kanagawa Psychiatric Center, Yokohama, Japan Neuropshychi., Grad. Sch. of Med., Univ of Tokyo, Tokyo, Japan
2
Div. of
Objectives: Repetitive transcranial magnetic stimulation (rTMS) over primary motor cortex has been reported to induce an alternation of the background oscillatory activity around the stimulation site, especially for alpha band spectral power. However, modulating effects on background activities of prefrontal stimulation have little been known so far. In the present study, electroencephalogram (EEG) spectral power at prefrontal region were investigated before and after consecutive 10 rTMS sessions over left dorsolateral prefrontal cortex (DLPFC), to explore any longitudinal changes in spectral power at theta, alpha, and beta band oscillations. Methods: Twenty-four patients with major depression underwent 10 daily rTMS sessions over two weeks. The stimulation site was left DLPFC determined by ultrasound-based navigation system. Stimulation frequency was 20 Hz and intensity was 90-110% resting motor threshold, with total pulses per week of 5000. Scalp EEG recording was performed before and after 10 consecutive rTMS sessions. In order to focus on the prefrontal region, Fast Fourier Transformation (FFT) analyses were performed on EEG data derived from Fp1, Fp2, F3, F4 electrodes using EEGLAB software. Spectral power values of each frequency band were compared applying paired T test using SPSS software. Results: The paired T test revealed a significant increase in alpha spectral power and an increasing trend of theta spectral power at Fp1 electrode after the 10 serial rTMS sessions. Conclusions: The present study suggests that the power of alpha and theta band oscillations recorded at Fp1 electrode could be enhanced by high frequency rTMS sessions over left DLPFC, which may be related to the neuromodulation on the stimulated region. doi:10.1016/j.neures.2011.07.1809
P4-v06 Examing the calcium response of white matter glia cells with calcium imaging Tsunehiro Takeuchi , Tatsuhiro Hisatsune Dep. of Integrated Biosci., Grad. Sch. of Frontier Sciences, The University of Tokyo, Kashiwa, Japan The objective of this study is to examine the calcium responses of white matter glia cells with calcium imaging technique. It is known that glia cells play an important role in transmitting information in addition to neurons. Using SR101 as a specific marker of glia cells, we applied various drugs to brain slices of mice. We have demonstrated that glia cells responded to neurotransmitters such as ATP and P2Y1 agonist (N)-methanocarba-2MeSADP. Furthermore, we have demonstrated that glutamate evokes calcium signal, but mGluR5 agonist DHPG did not produce the same result. These results mean that whitematter glia cells do not always have all glutamate receptor subtypes. We need to use agonists and antagonists of glutamate for investigating what kind of receptor subtypes are involved. And, we demonstrated that glia cells responded to anti-inflammatory substances such as adenosine A2A agonist CGS21680, but did not respond to GPR40/GPR120 agonist GW9508. We need to examine the change of the response to antiinflammatory substances under inflammatory conditions. Research fund: 22120505. doi:10.1016/j.neures.2011.07.1811
P4-v07 Intrasulcal electrocorticography in macaque monkeys Keisuke Kawasaki 1 , Takeshi Matsuo 1,2 , Takahiro Osada 3 , Hirohito Sawahata 1 , Takafumi Suzuki 4 , Masahiro Shibata 5 , Naohisa Miyakawa 1 , Kiyoshi Nakahara 6 , Noboru Sato 5 , Kensuke Kawai 2 , Nobuhito Saito 2 , Isao Hasegawa 1 1
Dept Physiol, Niigata Univ Sch Med 2 Dept Neurosurg, Univ Tokyo Sch Med Dept Physiol, Univ Tokyo Sch Med 4 Grad Sch Info Sci and Tech, Univ Tokyo 5 Dept Anat, Niigata Univ Sch Med 6 National Center of Neurol and Psych 3
The highly evolved primate’s brain has deep cerebral sulci, and both gyral and intrasulcal cortical regions have been implicated in important functional processes. Electrocorticography (ECoG) has become a potent methodology for large area recording and stimulation. However, direct experimental access is typically limited to gyral regions, since placing probes into sulci is difficult without damaging the surrounding tissues. Here we describe a novel method for intrasulcal ECoG in macaques by combining minimally invasive
P4-v03 Establishment of new approaches to understanding the brain glycogen metabolism—By NMR spectroscopic technique using 13 C-labeled glucose and lactate Hirokazu Mizokawa Tomoyuki Kanamatsu
, George
Kokubu, Youichi
Kobayashi,
Department of Environmental Engineering for Symbiosis, Faculty of Engineering, Soka University, Tokyo, Japan It has been reported that the concentration of glycogen in brain is one tenth of that in liver and the localized-distribution of glycogen is found only in astrocytes. Magistretti et al. reported that one possible neuro-protective mechanism of glial glycogen might be to provide lactate as fuel for neurons. However, the physiological function and metabolic role of brain glycogen are still unclear. Due to postmortem degradation, it is difficult to determine the concentration of brain glycogen and lactate. So, we established a new approach to know the brain glycogen metabolism. After 24 h starvation, the rat were raised only [1–13 C]-glucose solution (10%, w/v) for 6, 12, 24 h, and then collect blood under anesthesia and sacrificed by microwave treatment (5.0 kW, 1.2 s) to the head. The brain, liver and blood was homogenized with 6% PCA and divided into two portions respectively. One portion was used for glucose assay. The other portion was added NaBH4 to change the NMR chemical shift of glucose, and then incubated for 16 h after adding amyloglucosidase for measuring the glycogen concentration. 1 H NMR shows the fractional enrichment (FE) of glucose and lactate (which indicates the % of glucose used for synthesis glycogen and lactate). 13 C NMR also shows the amount of 13 C incorporated into glycogen and lactate from [1–13 C]-glucose. The blood glucose level was almost normal from 6 to 24 h after the onset of [1–13 C]-glucose solution and the values of FE of blood glucose and lactate was about 80% and 35%, respectably. The FE of glucose and lactate in the brain was also detected by 1 H NMR. These methods for knowing the metabolism of glucose, lactate and glycogen may be useful for understanding the brain energy metabolism.
e413
P4-v05 The selective injection system into hippocampus CA1 utilizing theta oscillation Kogo Takamiya , Jyoji Tsutajima, Takato Kunitake Dep. of Integrative Physiology, Faculty of Med., Unv. of Miyazaki, Miyazaki, Japan Hippocampus CA1 has been intensively studied due to its important roles in synaptic plasticity underlying learning/memory. In particular, much effort has been devoted to clarify its molecular mechanism of in vitro synaptic plasticity paradigm, LTP (long-term potentiation). Hippocampus CA1 LTP has been studied using acute brain slices. In contrast, it is difficult to mimic LTP in dissociated cultured neurons, suggesting that hippocampus LTP is expressed by unknown mechanisms including a network connection. In addition, several different forms of synaptic plasticity are reported in various brain regions and ages, presumably expressed in individual mechanisms. These complicated natures of LTP provoke difficulty in creating a detailed analysis of the molecular mechanism. One approach to this study is directly injecting viruses expressing cDNA/shRNA into hippocampus CA1 and analyzing neuronal functions in normal neuronal circuitry. In general, virus is injected via pipette that is inserted from the top of the brain cortex. However, by this approach, it is difficult to locate CA1 accurately using a pipette, since CA1 pyramidal cell layer is only 0.2 mm in width. In the present study, we have established a system to accurately introduce viral vectors in the stereotactic injection system into mouse hippocampus CA1 by monitoring theta oscillation. We decided the correct depth of the pipette tip based on the integrated values of theta oscillation at each depth. This approach allows us to inject virus accurately and provide an efficient method to transfer genes into hippocampus CA1 neurons, in the studies of molecular mechanisms of synaptic plasticity and other neuronal functions. Research fund: The Naito Foundation Natural Science Scholarship, Uehara Memorial Foundation, KAKENHI 22300122. doi:10.1016/j.neures.2011.07.1810
doi:10.1016/j.neures.2011.07.1808
P4-v04 Neuromodulation of prefrontal background oscillatory activities with high-frequency repetitive transcranial magnetic stimulation Yoshihiro Noda 1 , Motoaki Nakamura 1 , Takashi Saeki 1 , Hideo Iwanari 1 , Kiyoto Kasai 2 1
Kinko Hospital, Kanagawa Psychiatric Center, Yokohama, Japan Neuropshychi., Grad. Sch. of Med., Univ of Tokyo, Tokyo, Japan
2
Div. of
Objectives: Repetitive transcranial magnetic stimulation (rTMS) over primary motor cortex has been reported to induce an alternation of the background oscillatory activity around the stimulation site, especially for alpha band spectral power. However, modulating effects on background activities of prefrontal stimulation have little been known so far. In the present study, electroencephalogram (EEG) spectral power at prefrontal region were investigated before and after consecutive 10 rTMS sessions over left dorsolateral prefrontal cortex (DLPFC), to explore any longitudinal changes in spectral power at theta, alpha, and beta band oscillations. Methods: Twenty-four patients with major depression underwent 10 daily rTMS sessions over two weeks. The stimulation site was left DLPFC determined by ultrasound-based navigation system. Stimulation frequency was 20 Hz and intensity was 90-110% resting motor threshold, with total pulses per week of 5000. Scalp EEG recording was performed before and after 10 consecutive rTMS sessions. In order to focus on the prefrontal region, Fast Fourier Transformation (FFT) analyses were performed on EEG data derived from Fp1, Fp2, F3, F4 electrodes using EEGLAB software. Spectral power values of each frequency band were compared applying paired T test using SPSS software. Results: The paired T test revealed a significant increase in alpha spectral power
P4-v06 Examing the calcium response of white matter glia cells with calcium imaging Tsunehiro Takeuchi , Tatsuhiro Hisatsune Dep. of Integrated Biosci., Grad. Sch. of Frontier Sciences, The University of Tokyo, Kashiwa, Japan The objective of this study is to examine the calcium responses of white matter glia cells with calcium imaging technique. It is known that glia cells play an important role in transmitting information in addition to neurons. Using SR101 as a specific marker of glia cells, we applied various drugs to brain slices of mice. We have demonstrated that glia cells responded to neurotransmitters such as ATP and P2Y1 agonist (N)-methanocarba-2MeSADP. Furthermore, we have demonstrated that glutamate evokes calcium signal, but mGluR5 agonist DHPG did not produce the same result. These results mean that whitematter glia cells do not always have all glutamate receptor subtypes. We need to use agonists and antagonists of glutamate for investigating what kind of receptor subtypes are involved. And, we demonstrated that glia cells responded to anti-inflammatory substances such as adenosine A2A agonist CGS21680, but did not respond to GPR40/GPR120 agonist GW9508. We need to examine the change of the response to antiinflammatory substances under inflammatory conditions. Research fund: 22120505. doi:10.1016/j.neures.2011.07.1811
P4-v07 Intrasulcal electrocorticography in macaque monkeys Keisuke Kawasaki 1 , Takeshi Matsuo 1,2 , Takahiro Osada 3 , Hirohito Sawahata 1 , Takafumi Suzuki 4 , Masahiro Shibata 5 , Naohisa Miyakawa 1 , Kiyoshi Nakahara 6 , Noboru Sato 5 , Kensuke Kawai 2 , Nobuhito Saito 2 , Isao Hasegawa 1 1
Dept Physiol, Niigata Univ Sch Med 2 Dept Neurosurg, Univ Tokyo Sch Med Dept Physiol, Univ Tokyo Sch Med 4 Grad Sch Info Sci and Tech, Univ Tokyo 5 Dept Anat, Niigata Univ Sch Med 6 National Center of Neurol and Psych 3
The highly evolved primate’s brain has deep cerebral sulci, and both gyral and intrasulcal cortical regions have been implicated in important functional processes. Electrocorticography (ECoG) has become a potent methodology for large area recording and stimulation. However, direct experimental access is typically limited to gyral regions, since placing probes into sulci is difficult without damaging the surrounding tissues. Here we describe a novel method for intrasulcal ECoG in macaques by combining minimally invasive