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Corticosubthalamic projections from area 3a in the cat, revealed by a retrograde WGA-HRP labeling
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HEMIBALLISMUS INDUCED BY MICROLESIONS OF MONKEY SUBTHALAMIC NUCLEUS (STN). IKUMA HAMADA*' AND MAHLON R, DELONG .2 ~Deoartment of Neurophysiol0~y. Tokyo Metrooolitan Institute for Neurosciences. 2-6 Musashidai. Fuchu-shi.Tokvo 183. Japan, =Department of Neuroloey. The Johns Hopkins University, School of Medicine, Baltimore. MD 21205. U.S.A. An attempt was made to develop an animal model of hemiballismus. In two awake monkeys, STN was experimentally lesioned and behavioral changes were analyzed. We designed an injection-recording device which allowed both injections of drugs and recording of neuronal activity at the injection site. A small amount of ibotenic acid (10,ug/l,ul) was injected into a target site in STN, with physiological guidance. Lesions were confined within the STN and the volume of each lesion was 8 % of the total volume of the nucleus. Movements in each limb were counted separately in a video tape record of the monkey's behavior. Twenty to 30 minutes after the injection, the frequency of movements increased in both upper and lower limbs contralateral to the inJection site. Severe dyskinesia developed in contralateral limbs after 60-80 minutes. The majority of the movements involved proximal joints. Many movements were violent and flinging in character. No significant change was detected in ipsilateral limbs. The dyskinesia was detectable for 4 to 6 hours. Additional inJections of ibotenic acid at intervals of 24 hours reproduced the dyskinesia with similar character and time course. The results suggest that a reliable model of human hemiballismus in monkeys can be produced by microlesion of neurons in STN, while sparing passing fibers.
C O R T I C O S U B T H A L A M I C PROJECTIONS FROM AREA 3A IN THE CAT, R E V E A L E D BY A R E T R O G R A D E WGA-HRP LABELING. TERUMI NODA and HIROSHI OKA t Department of Physiology r Fukui Medical School, Matsuoka, Fukui 910-11, Japan. The topographical distribution of cortical neurons projecting to the subthalamic nucleus (STN) in cats was investigated, using the retrograde W G A - H R P tracing method. The brain sections were treated with tetramethylbenzidine according to Mesulam. When W G A - H R P injection was made e l e c t r o p h o r e t i c a l l y in the lateral half of the STN (n=2), r e t r o g r a d e l y - l a b e l e d neurons were observed as pyramidal cells in layer V of the following cortical regions: the lateral part of the anterior sigmoid gyrus (area 4), the fundus of the p r e s y l v i a n gyrus (area 6), the medial part of the proreal gyrus (the medial prefrontal cortex), and, the most rostral part of the coronal gyrus (area 3a). Our result indicates that not only the frontal cortical areas but also area 3a, which is related with somatic deep sensation, influences STN function through their direct projections.
DIRECT PROJECTIONS FROM THE GLOBUS PALLIDUS TO THE TEMPORAL POLAR GYRUS IN THE CAT. YASUHIDE SHINONAGA , KAZUO I T O H , SHIGERU MATSUZAKI , REIKO OGAWA-MEGURO , HITOSHI OHISHI , AND NOBORU MIZUNO, Department of Norphological Brain Science, Faculty of Medicine, Kyoto U n i v e r s i t y , Kyoto 606, Japan. The globus p a l l i d u s (GP) of the cat (the homologue to the external segment of the GP in the primates) was found to send many p r o j e c t i o n f i b e r s to the temporal polar gyrus (TPG). The experiments were done in cats anesthetized with sodium pentobarbital (35 mg/kg, i . p . ) . When Phaseolus v u l g a r i s - l e u c o a g g l u t i n i n (PHA-L) was injected i n t o the middle levels of the GP, terminal l a b e l i n g in the neocortex was p a r t i c u l a r l y marked in the TPG. Labeled axon terminals and axons with v a r i c o s i t i e s were most abundant in layers I , I I and I l l , although they were d i s t r i b u t e d in a l l c o r t i c a l layers. When horseradish peroxidase conjugate to wheat germ a g g l u t i n i n (WGA-HRP) was injected into the TPG, both l a r g e r m u l t i p o l a r and smaller b i p o l a r GP neurons were labeled in the i p s i l a t e r a l GP; most frequently in the middle GP levels. The sections which were treated with the nickel-enhanced diaminobenzidine method f o r v i s u a l i z a t i o n of WGA-HRP were f u r t h e r immunostained f o r choline acetyltransferase (CHAT) a f t e r treatment with sodium azide f o r blocking residual enzyme a c t i v i t y of WGA-HRP. The vast m a j o r i t y of GP neurons with WGA-HRP granules exhibited ChAT-like immunoreactivity. The results indicate that both large and small GP neurons which send t h e i r axons to the TPG cortex are c h o l i n e r g i c .
HEMIBALLISMUS INDUCED BY MICROLESIONS OF MONKEY SUBTHALAMIC NUCLEUS (STN). IKUMA HAMADA*' AND MAHLON R, DELONG .2 ~Deoartment of Neurophysiol0~y. Tokyo Metrooolitan Institute for Neurosciences. 2-6 Musashidai. Fuchu-shi.Tokvo 183. Japan, =Department of Neuroloey. The Johns Hopkins University, School of Medicine, Baltimore. MD 21205. U.S.A. An attempt was made to develop an animal model of hemiballismus. In two awake monkeys, STN was experimentally lesioned and behavioral changes were analyzed. We designed an injection-recording device which allowed both injections of drugs and recording of neuronal activity at the injection site. A small amount of ibotenic acid (10,ug/l,ul) was injected into a target site in STN, with physiological guidance. Lesions were confined within the STN and the volume of each lesion was 8 % of the total volume of the nucleus. Movements in each limb were counted separately in a video tape record of the monkey's behavior. Twenty to 30 minutes after the injection, the frequency of movements increased in both upper and lower limbs contralateral to the inJection site. Severe dyskinesia developed in contralateral limbs after 60-80 minutes. The majority of the movements involved proximal joints. Many movements were violent and flinging in character. No significant change was detected in ipsilateral limbs. The dyskinesia was detectable for 4 to 6 hours. Additional inJections of ibotenic acid at intervals of 24 hours reproduced the dyskinesia with similar character and time course. The results suggest that a reliable model of human hemiballismus in monkeys can be produced by microlesion of neurons in STN, while sparing passing fibers.
C O R T I C O S U B T H A L A M I C PROJECTIONS FROM AREA 3A IN THE CAT, R E V E A L E D BY A R E T R O G R A D E WGA-HRP LABELING. TERUMI NODA and HIROSHI OKA t Department of Physiology r Fukui Medical School, Matsuoka, Fukui 910-11, Japan. The topographical distribution of cortical neurons projecting to the subthalamic nucleus (STN) in cats was investigated, using the retrograde W G A - H R P tracing method. The brain sections were treated with tetramethylbenzidine according to Mesulam. When W G A - H R P injection was made e l e c t r o p h o r e t i c a l l y in the lateral half of the STN (n=2), r e t r o g r a d e l y - l a b e l e d neurons were observed as pyramidal cells in layer V of the following cortical regions: the lateral part of the anterior sigmoid gyrus (area 4), the fundus of the p r e s y l v i a n gyrus (area 6), the medial part of the proreal gyrus (the medial prefrontal cortex), and, the most rostral part of the coronal gyrus (area 3a). Our result indicates that not only the frontal cortical areas but also area 3a, which is related with somatic deep sensation, influences STN function through their direct projections.
DIRECT PROJECTIONS FROM THE GLOBUS PALLIDUS TO THE TEMPORAL POLAR GYRUS IN THE CAT. YASUHIDE SHINONAGA , KAZUO I T O H , SHIGERU MATSUZAKI , REIKO OGAWA-MEGURO , HITOSHI OHISHI , AND NOBORU MIZUNO, Department of Norphological Brain Science, Faculty of Medicine, Kyoto U n i v e r s i t y , Kyoto 606, Japan. The globus p a l l i d u s (GP) of the cat (the homologue to the external segment of the GP in the primates) was found to send many p r o j e c t i o n f i b e r s to the temporal polar gyrus (TPG). The experiments were done in cats anesthetized with sodium pentobarbital (35 mg/kg, i . p . ) . When Phaseolus v u l g a r i s - l e u c o a g g l u t i n i n (PHA-L) was injected i n t o the middle levels of the GP, terminal l a b e l i n g in the neocortex was p a r t i c u l a r l y marked in the TPG. Labeled axon terminals and axons with v a r i c o s i t i e s were most abundant in layers I , I I and I l l , although they were d i s t r i b u t e d in a l l c o r t i c a l layers. When horseradish peroxidase conjugate to wheat germ a g g l u t i n i n (WGA-HRP) was injected into the TPG, both l a r g e r m u l t i p o l a r and smaller b i p o l a r GP neurons were labeled in the i p s i l a t e r a l GP; most frequently in the middle GP levels. The sections which were treated with the nickel-enhanced diaminobenzidine method f o r v i s u a l i z a t i o n of WGA-HRP were f u r t h e r immunostained f o r choline acetyltransferase (CHAT) a f t e r treatment with sodium azide f o r blocking residual enzyme a c t i v i t y of WGA-HRP. The vast m a j o r i t y of GP neurons with WGA-HRP granules exhibited ChAT-like immunoreactivity. The results indicate that both large and small GP neurons which send t h e i r axons to the TPG cortex are c h o l i n e r g i c .