- Email: [email protected]
Developmental changes in mouse striatal neurons differ to those seen in rat
Abstracts / Neuroscience Research 58S (2007) S1–S244
P1-d41 Responses of oligodendrocyte progenitors in the spinal
P1-d44 Developmental changes in mouse striatal neurons dif-
cord following dorsal rhizotomy in the adult rat
fer to those seen in rat
Teruyoshi Kondo 1 , Kei-Ichiro Nakamura 2 , Norito Takamura 3 , Jin Tokumasa 3 , Ryuichi Yamamoto 3 1 School of Health Science, Kyushu University of Health & Welfare, Nobeoka, Japan; 2 Department of Anatomy, Kurume University School of Medicine, Kurume, Japan; 3 School of Pharmacology and Pharmaceutical Science, Kyushu University of Health & Welfare, Nobeoka, Japan
Hyunchul Lee, Atomu Sawatari Department of Physiology and Bosch Institute, University of Sydney, Australia
In the adult spinal cord, oligodendrocyte progenitors (OPs) are distributed throughout both the white and gray matter, but little is known concerning the potential role of OPCs. We examined the response of OPs to the degeneration of the central processes of primary sensory neurons induced by dorsal root transection. OPs were identified by staining with antibodies against NG2 and Olig2. Axonal degeneration resulted in a prompt response of OPs in the dorsal funiculus and dorsal horn, consisting of morphological transformation, cellular proliferation, and upregulation of NG2 expression days 2–4 after surgery. Olig2 staining was exclusively nuclear until 3 weeks after surgery, and thereafter a clear cytoplasmic pattern of Olig2 staining was found in numerous cells in the dorsal funiculus. The majority of cells with nuclear Olig2 co-expressed GFAP. These results suggest that axonal degeneration induces a unique sequence of changes of OPs and that a subpopulation of the newly generated OPs differentiate into astrocytes.
P1-d42 Large-scale change in the corticofugal projections in rats with neonatal hemi-decortication Takahashi 1,5 ,
Vattanajun 1,4 ,
Umeda 1 ,
Masahito Anusara Tatsuya Kaoru Isa 1,2 , Tadashi Isa 1,2,3 1 Department of Developmental Physiology, National Institute of Physiology Science, Okazaki, Japan; 2 JST, CREST, Kawaguchi, Japan; 3 Life Science, The Graduate University, Advanced Study, Hayama, Japan; 4 Department of Physiology, Phramongkutklao Col., Med., Bangkok, Thailand; 5 Department of Orthopaedic Surgery, Kyorin University, Mitaka, Japan
To study the mechanism of functional recovery of forelimb movements in rats that received unilateral decortication at PND5, descending projections from sensorimotor cortex (SMC) of the remaining hemisphere was studied neuroanatomically and electrophysiologically at their adult stage. After injection of biotinylated dextran amine, massive aberrant terminations were observed in the contralateral red nucleus and pontine nucleus, and ipsilateral dorsal column nucleus and gray matter at the cervical segments. Electrical stimulation of the remaining medullary pyramid evoked clear aberrant negative field potentials in dorsal horn of ipsilateral cervical segments and polysynaptic EPSPs in ipsilateral forelimb motoneurons. These aberrant corticofugal projections may underlie the functional restoration of forelimb movements in these animals.
S91
Medium spiny neurons (MSN) of the mammalian striatum are thought to integrate and filter cortical input, and hence play a major role in behavior. Whilst much basal ganglia research has been performed in rats thus far, the advent of genetic techniques favors the mouse model. In order to determine the developmental changes occurring in mouse MSNs, we performed whole-cell recordings and labeled individual neurons in mouse brain slices at different ages. Our analyses thus far indicate significant differences in morphometric and physiological parameters between age groups. Furthermore, developmental trends in our results differ with those reported in rats. In particular, we report the presence of an inward rectifying potassium current (Kir ) in all MSNs of mice as young as postnatal day 10. Kir is an important determinant of membrane potential states, and hence vital to the role of MSNs in filtering cortical input. Our results suggest that systematic characterization of mouse striatal neurons may be an important step in basal ganglia research. University of Sydney Research and Development Grant.
P1-d45 Sensory basis of motor program selection in the cricket behavior
Tetsuya Matsuura 1 , Masamichi Kanou 2 , Shinsuke Morita 2 , Tsuneo Yamaguchi 3 1 Department of Welfare Engineering, Iwate University, Morioka, Japan; 2 Graduate School of Science and Engineering, Ehime University, Matsuyama, Japan; 3 Kawasaki Coll. Allied Health Profession, Kurashiki, Japan Crickets react differently to an air puff stimulus, that is, running and/or jumping on the ground, swimming when on a water surface and flying when suspended in the air. Leg ablated crickets occasionally react to an air puff by flying even when they are placed on a water surface. Sensory inputs from legs are thus important for the behavioral selection. Some small hair sensilla on the legs were equipped with two to five sensory neurons. All such hair sensilla had a tiny pore at the tip. These findings suggest that they are chemosensitive hairs. Electrophysiological investigations proved that some of the sensilla were accompanied with water receptor cells. Therefore, such sensilla are thought to play an important role for the behavioral selection between swimming and flying. On the other hand, crickets placed on a high viscosity methylcellulose solution sometimes show walking. Therefore, the resistance force from substrate to the legs was thought to be important for the initiation of walking.
Research funds: JST, CREST, Kawaguchi
P1-d43 Exercise has a neuroprotective effect in parkinsonian rat model Naoki Tajiri, Tetsuro Shingo, Wenji Yuan, Takamasa Morimoto, Tomohito Kadota, Takao Yasuhara, Yasuyuki Miyoshi, Isao Date Department of Neurological Surgery, University of Okayama, Okayama, Japan We examined the effects of compulsive exercise in rat model of parkinsonian disease. After 6-hydroxydopamine injection into the striatum, the rats were forced to run on the treadmill for 30 min each day. The exercise group displayed a significant decrease in amphetamine-induced rotational behavior and a significant preservation of tyrosine hydroxylase (TH)-positive fibers in the striatum and TH-positive neurons in the substantia nigra pars compacta (SNc) compared with non-exercised one. The great number of the Bromodeoxyuridine-positive cells and Doublecortinpositive cells were found in the subventricular zone in the exercise group. Some of them were migrated toward the lesioned striatum and differentiated into neurons. The mechanism is considered that neurotrophic factors, especially GDNF or neurotrophins, increase throughout the striatum or SNc by exercise. These results suggest that exercise in the parkinsonian disease may have a neuroprotective effect or enhance the neurogenesis.
P1-d46 Neurons expressing GAD 67 and glycine transporter 2 mRNA in and around the trigeminal motor nucleus of the rat Akira Kawata, Hiroyuki Hayashi, Hideko Tsuzuki, Shigehiko Oguri, Tomohisa Sugiyama, Tadaomi Akagi, Kazuyoshi Higashi, Osamu Takahashi Division of Histology and Neuroanatomy, Department of Anatomy, Kanagawa Dental College, Yokosuka, Japan The trigeminal motor nucleus (Vm) and its surrounding neuropil contain commissural GABAergic and glycinergic neurons that send axons to contralateral Vm. In the present study, we used digoxigenin labeled probes to detect GAD 67 and glycine transporter 2 (GLYT 2) mRNA by in situ hybridization. As a result, expressions of GAD 67 and GLYT 2 mRNAs were observed in and around Vm. Some neurons expressed GAD 67 mRNA or GLYT 2 mRNA, respectively, and some neurons expressed both mRNAs. Previous studies have shown that GAD 67 and GLYT 2 are often co-localized in trigeminal premotoneurons. Our results also indicate that some neurons in and around Vm coexpress GAD 67 and GLYT 2 mRNA.
P1-d41 Responses of oligodendrocyte progenitors in the spinal
P1-d44 Developmental changes in mouse striatal neurons dif-
cord following dorsal rhizotomy in the adult rat
fer to those seen in rat
Teruyoshi Kondo 1 , Kei-Ichiro Nakamura 2 , Norito Takamura 3 , Jin Tokumasa 3 , Ryuichi Yamamoto 3 1 School of Health Science, Kyushu University of Health & Welfare, Nobeoka, Japan; 2 Department of Anatomy, Kurume University School of Medicine, Kurume, Japan; 3 School of Pharmacology and Pharmaceutical Science, Kyushu University of Health & Welfare, Nobeoka, Japan
Hyunchul Lee, Atomu Sawatari Department of Physiology and Bosch Institute, University of Sydney, Australia
In the adult spinal cord, oligodendrocyte progenitors (OPs) are distributed throughout both the white and gray matter, but little is known concerning the potential role of OPCs. We examined the response of OPs to the degeneration of the central processes of primary sensory neurons induced by dorsal root transection. OPs were identified by staining with antibodies against NG2 and Olig2. Axonal degeneration resulted in a prompt response of OPs in the dorsal funiculus and dorsal horn, consisting of morphological transformation, cellular proliferation, and upregulation of NG2 expression days 2–4 after surgery. Olig2 staining was exclusively nuclear until 3 weeks after surgery, and thereafter a clear cytoplasmic pattern of Olig2 staining was found in numerous cells in the dorsal funiculus. The majority of cells with nuclear Olig2 co-expressed GFAP. These results suggest that axonal degeneration induces a unique sequence of changes of OPs and that a subpopulation of the newly generated OPs differentiate into astrocytes.
P1-d42 Large-scale change in the corticofugal projections in rats with neonatal hemi-decortication Takahashi 1,5 ,
Vattanajun 1,4 ,
Umeda 1 ,
Masahito Anusara Tatsuya Kaoru Isa 1,2 , Tadashi Isa 1,2,3 1 Department of Developmental Physiology, National Institute of Physiology Science, Okazaki, Japan; 2 JST, CREST, Kawaguchi, Japan; 3 Life Science, The Graduate University, Advanced Study, Hayama, Japan; 4 Department of Physiology, Phramongkutklao Col., Med., Bangkok, Thailand; 5 Department of Orthopaedic Surgery, Kyorin University, Mitaka, Japan
To study the mechanism of functional recovery of forelimb movements in rats that received unilateral decortication at PND5, descending projections from sensorimotor cortex (SMC) of the remaining hemisphere was studied neuroanatomically and electrophysiologically at their adult stage. After injection of biotinylated dextran amine, massive aberrant terminations were observed in the contralateral red nucleus and pontine nucleus, and ipsilateral dorsal column nucleus and gray matter at the cervical segments. Electrical stimulation of the remaining medullary pyramid evoked clear aberrant negative field potentials in dorsal horn of ipsilateral cervical segments and polysynaptic EPSPs in ipsilateral forelimb motoneurons. These aberrant corticofugal projections may underlie the functional restoration of forelimb movements in these animals.
S91
Medium spiny neurons (MSN) of the mammalian striatum are thought to integrate and filter cortical input, and hence play a major role in behavior. Whilst much basal ganglia research has been performed in rats thus far, the advent of genetic techniques favors the mouse model. In order to determine the developmental changes occurring in mouse MSNs, we performed whole-cell recordings and labeled individual neurons in mouse brain slices at different ages. Our analyses thus far indicate significant differences in morphometric and physiological parameters between age groups. Furthermore, developmental trends in our results differ with those reported in rats. In particular, we report the presence of an inward rectifying potassium current (Kir ) in all MSNs of mice as young as postnatal day 10. Kir is an important determinant of membrane potential states, and hence vital to the role of MSNs in filtering cortical input. Our results suggest that systematic characterization of mouse striatal neurons may be an important step in basal ganglia research. University of Sydney Research and Development Grant.
P1-d45 Sensory basis of motor program selection in the cricket behavior
Tetsuya Matsuura 1 , Masamichi Kanou 2 , Shinsuke Morita 2 , Tsuneo Yamaguchi 3 1 Department of Welfare Engineering, Iwate University, Morioka, Japan; 2 Graduate School of Science and Engineering, Ehime University, Matsuyama, Japan; 3 Kawasaki Coll. Allied Health Profession, Kurashiki, Japan Crickets react differently to an air puff stimulus, that is, running and/or jumping on the ground, swimming when on a water surface and flying when suspended in the air. Leg ablated crickets occasionally react to an air puff by flying even when they are placed on a water surface. Sensory inputs from legs are thus important for the behavioral selection. Some small hair sensilla on the legs were equipped with two to five sensory neurons. All such hair sensilla had a tiny pore at the tip. These findings suggest that they are chemosensitive hairs. Electrophysiological investigations proved that some of the sensilla were accompanied with water receptor cells. Therefore, such sensilla are thought to play an important role for the behavioral selection between swimming and flying. On the other hand, crickets placed on a high viscosity methylcellulose solution sometimes show walking. Therefore, the resistance force from substrate to the legs was thought to be important for the initiation of walking.
Research funds: JST, CREST, Kawaguchi
P1-d43 Exercise has a neuroprotective effect in parkinsonian rat model Naoki Tajiri, Tetsuro Shingo, Wenji Yuan, Takamasa Morimoto, Tomohito Kadota, Takao Yasuhara, Yasuyuki Miyoshi, Isao Date Department of Neurological Surgery, University of Okayama, Okayama, Japan We examined the effects of compulsive exercise in rat model of parkinsonian disease. After 6-hydroxydopamine injection into the striatum, the rats were forced to run on the treadmill for 30 min each day. The exercise group displayed a significant decrease in amphetamine-induced rotational behavior and a significant preservation of tyrosine hydroxylase (TH)-positive fibers in the striatum and TH-positive neurons in the substantia nigra pars compacta (SNc) compared with non-exercised one. The great number of the Bromodeoxyuridine-positive cells and Doublecortinpositive cells were found in the subventricular zone in the exercise group. Some of them were migrated toward the lesioned striatum and differentiated into neurons. The mechanism is considered that neurotrophic factors, especially GDNF or neurotrophins, increase throughout the striatum or SNc by exercise. These results suggest that exercise in the parkinsonian disease may have a neuroprotective effect or enhance the neurogenesis.
P1-d46 Neurons expressing GAD 67 and glycine transporter 2 mRNA in and around the trigeminal motor nucleus of the rat Akira Kawata, Hiroyuki Hayashi, Hideko Tsuzuki, Shigehiko Oguri, Tomohisa Sugiyama, Tadaomi Akagi, Kazuyoshi Higashi, Osamu Takahashi Division of Histology and Neuroanatomy, Department of Anatomy, Kanagawa Dental College, Yokosuka, Japan The trigeminal motor nucleus (Vm) and its surrounding neuropil contain commissural GABAergic and glycinergic neurons that send axons to contralateral Vm. In the present study, we used digoxigenin labeled probes to detect GAD 67 and glycine transporter 2 (GLYT 2) mRNA by in situ hybridization. As a result, expressions of GAD 67 and GLYT 2 mRNAs were observed in and around Vm. Some neurons expressed GAD 67 mRNA or GLYT 2 mRNA, respectively, and some neurons expressed both mRNAs. Previous studies have shown that GAD 67 and GLYT 2 are often co-localized in trigeminal premotoneurons. Our results also indicate that some neurons in and around Vm coexpress GAD 67 and GLYT 2 mRNA.