Transcript 슬라이드 제목 없음
Basal Ganglia Won Taek Lee, M.D., Ph.D. Basal Ganglia Introduction Traditional Concepts of Basal Ganglia Corpus Striatum Caudate Nucleus Lenticular Nucleus Striatum Paleostriatum Pallidum Putamen Globus Pallidus Corpus Amygdaloideum Neostriatum Archistriatum Lateral surface of basal ganglia 1. Putamen 2. Tail of caudate nucleus 3. Caudatolenticular gray bridge 4. Amygdaloid body 5. thalamus 1. head of caudate nucelus 2. body of caudate nucelus 3. caudatolenticular gray bridge 4. putamen 5. tail of caudate nucleus 6. external segment of globus pallidus 7. internal segment of globus pallidus 8. amygdaloid body 9. nucleus accumbens septi Medial surface of basal ganglia Basal Ganglia Components Components of Basal Ganglia Corpus Striatum Striatum ----- Caudate Nucleus & Putamen Pallidum ----- Globus Pallidus (GP) Substantia Nigra Pars Compacta (SNc) Pars Reticulata (SNr) Subthalamic Nucleus (STN) Ventral Striatum and Ventral Pallidum Nucleus Accumbens Septi Non cholinergic portion of Substantia Innominata Basal Ganglia Components STRIATUM Caudate Nucleus Head, (Corpus), Tail caudatolenticular gray bridge Putamen Ventral Striatum: Nucleus Accumbens (Septi) Basal Ganglia Components Striatal Compartments (Mosaic or Modular Organization) 1. Striosome (Patches) - 10-20% of total striatal mass - low acetylcholinesterase (AchE) activity - high substance P (SP), neurotensin (NT), tyrosine hydroxylase - high expression of D1 dopamine receptor - high opiate receptor 2. Matrix - high acetylcholinesterase (AchE) activity - high somatostatin (SRIF) activity - high D2 dopamine receptor Spiny I neuron Spiny II neuron Aspiny I neuron Aspiny II neuron Aspiny III neuron Neurogliform cell Basal Ganglia Components Striosome and Matrix compartment AchE Basal Ganglia Components Inputs to the spiny striatal neurons distal – extrinsic proximal - intrinsic Basal Ganglia Components PALLIDUM Globus Pallidus (Pallidum) Internal or Medial Segment (GPi) internal medullary lamina External or Lateral Segment (GPe) Ventral Pallidum Non-cholinergic portions of substantia innominata Basal Ganglia Components Substantia Nigra Pars Compacta (SNc) Dopaminergic Cell Group (A9) cf. Ventral Tegmental Area (VTA, A10) Retrorubral Area (A8) Pars Reticulata (SNr) Non-dopaminergic Portion GABAergic Neuron Basal Ganglia Components Subthalamus Subthalamic Nucleus (STN) zona incerta Field of Forel H H1 H2 ansa lenticularis thalamic fasciculus lenticular fasciculus Components of Basal Ganglia Putamen Globus pallidus external segment internal segment Subthalamic Nucleus Substantia nigra Internal capsule Basal Ganglia Components Subthalamic Nucleus 1. epithalamus 2. dorsal thalamus 3. subthalamus 3-1. subthalamic nucleus 3-2. zona incerta 3-3. globus pallidus 4. hypothalamus 5. putamen arrow: internal capsule Origin of subthalamic nucleus and putamen (Kuhlenbeck) Basal Ganglia Connections Input Portion STRIATUM (Caudate Nucleus and Putamen) Output Portion 1. PALLIDUM (Globus Pallidus) 2. SNr (Substantia Nigra, Pars Reticulata) Basal Ganglia Connections STRIATUM Afferents from 1. Cerebral Cortex [Corticostriatal Projection] 2. Thalamus (CM-PF complex) [Thalamostriatal Projection] 3. SNc (Substantia Nigra, pars compacta), Ventral Tegmental Area (VTA, A10) and A8(Retrorubral Area) [Nigrostriatal Projection] 4. Dorsal Raphe Nucleus (B6, B8) [Raphestriatal Projection] 5. Amygdaloid Nuclear Complex [Amygdalostriatal Projection] Efferents to 1. Pallidum (GPi & GPe) [Striopallidal Projection] 2. SNr [Strionigral Projection] 3. SNc from striosome Afferent Connections of Basal Ganglia Input-Output Relationship of Basal Ganglia 1. striopallidal fiber 2. strionigral fiber 3. strionigral fiber from striosome to SNc 4. ventrostrioventro-pallidal fiber Basal Ganglia Connections PALLIDUM (Globus Pallidus) Afferents from 1. Striatum [Striatopallidal Projection] 2. STN <GPi & GPe> [Subthalamopallidal Projection] Efferents to 1. Thalamus (VLo, VApc, CM) <GPi> [Pallidothalamic Projection] 2. STN <GPe> [Pallidosubthalamic Projection] SNr (Substantia Nigra, Pars Reticulata) Afferents from Striatum [Striatonigral Projection] Efferents to 1. Thalamus (VLm, VAmc, MD) [Nigrothalamic Projection] 2. Brain Stem Nucleus: Tectum (Superior Colliculus) & Pedunculopontine Nucleus (PPN) Efferent Connections of Basal Ganglia Basal Ganglia Connections Pallidothalamic Fibers from GPi to VLo, VApc, CM Ansa Lenticularis from outer (lateral) portion of GPi fibers sweep ventromedially and rostrally around the posterior limb of the internal capsule enters Forel’s field H Lenticular Fasciculus from inner (medial) portion of GPi perforate internal capsule enters Forel’s field H2 Thalamic fasciculus ansa lenticularis, lenticular fasciculus and cerebellothalamic fibers Forel’s field H1 Connections of the Basal Ganglia amygdaloid body Cerebral Cortex raphe STRIATUM Thalamus STN SNc Pallidum SNr habenular nucleus tectum PPN (superior colliculus) (pedunculopontine nucleus) Basal Ganglia (Main Motor Circuit) Primary Motor Area (M I) Connections Supplementary Motor Area (SMA) STRIATUM (Putamen) pyramidal tract THALAMUS (VLo, VApc, CM) LMN ansa lenticularis lenticular fasciculus PALLIDUM (GPi) Basal Ganglia (Prefronatal Complex Loop) Primary Motor Area (M I) Connections Prefrontal Association Cortex STRIATUM (Caudate Nucleus) THALAMUS SNr pyramidal tract (VLm, VAmc, MD) LMN (Substantia Nigra, pars reticulata) Basal Ganglia (Microcircuitary) Connections glutamate Motor Cortex Striatum + + glutamate ? glutamate - + VA-VL complex GABA GABA GP, SNr Basal Ganglia (Limbic Loop) Orbitofrontal Cortex Anterior Cingulate Gyrus Hippocampal Formation THALAMUS (VAmc, MD) Connections Ventral Striatum Caudate Nucleus Ventral Pallidum GPi, SNr Basal Ganglia (Oculomotor Loop) Primary Motor Area (M I) Connections Frontal Eye Field (area 8) STRIATUM (Caudate Nucleus) THALAMUS SNr pyramidal tract (VLm, VAmc, MD) LMN Tectum (Substantia Nigra, pars reticulata) Basal Ganglia (SNc and CM-PF nuclear complex) Connections Striatum Striatum THALAMUS (CM-PF) SNc Pallidum Pallidum Basal Ganglia (Brain Stem Efferents) aves (birds) DIP (thalamus) GPi SpL nDCP Phylogeny Neostriatum Intermediale (motor cortex) Tectum (superior colliculus) SNr mammals GPi SNr VA-VL complex (thalamus) motor cortex nPC Tectum (superior colliculus) Basal Ganglia (STN) Connections Subthalamic Nucleus Cerebral Coretx STN subthalamic fasciculus Output Portion of Basal Ganglia Thalamus (CM-PF) PPN GPe GPi SNr Basal Ganglia (Ventral Striatum and Ventral Pallidum) Connections Hippocampal Formation Basolateral Amygdala Thalamus (MD) Temporal & Frontal Cortex SNc, VTA & Dorsal Raphe Basolateral Amygdala Ventral Striatum Ventral Pallidum Thalamus (MD) PPN & VTA Basal Ganglia (Brain Stem Efferents) Connections Brain Stem & Spinal Cord Striatum (caudate nucleus) Tectum tectospinal tract (superior colliculus) Lower Motor Neuron GPi, SNr PPN (midbrain locomotor region) Basal Ganglia via reticular formation Basal Ganglia and Pyramidal Tract SMA (supplementary motor area) upper motor neuron UMN pyramidal tract lower motor neuron LMN BASAL GANGLIA CIRCUIT Basal Forebrain Area Components BASAL FORBRAIN AREA (Heimer) Ventral Striatum, Part of Ventral Pallidum Basal Nucleus of Meynert (Ch4) Extended Amygdala cf. Cholinergic Cell Groups (Mesulam) (Magnocellular Basomedial Telencephalic Complex ) 1. Ch1 (Medial Septal Nucleus) 2. Ch2 (Nucleus of Diagonal Band of Broca) 3. Ch3 (Nucleus of Diagonal Band of Broca) 4. Ch4 (Basal Nucleus of Meynert) 5. Ch5 (Pedunculopontine Tegmental Nucleus) Basal Ganglia Functional Consideration Functional Consideration 1. Selection of “Preprogramed (learned) motor plans” Basal Gangla Circuit ---- Selection Mechanism Selection Inability -------- Akinesia and Hypokinesia Faulty Selection ----------- Hyperkinesia 2. Generation (learning) of motor programs Programming of several motor fragments into complex motor routines Cerebral Palsy ------------- Disordered motor program SYDENHAM’S CHOREA Clinical Feature Principal Pathologic Lesion: Corpus Striatum - Complication of Rheumatic Fever - Fine, disorganized , and random movements of extremities, face and tongue - Accompanied by Muscular Hypotonia - Typical exaggeration of associated movements during voluntary activity - Usually recovers spontaneously in 1 to 4 months HUNTINGTON’S CHOREA Clinical Feature - Predominantly autosomal dominantly inherited chronic fatal disease (Gene: chromosome 4) - Insidious onset: Usually 40-50 - Choreic movements in onset - Frequently associated with emotional disturbances - Ultimately, grotesque gait and sever dysarthria, progressive dementia ensues. Principal Pathologic Lesion: Corpus Striatum (esp. caudate nucleus) and Cerebral Cortex HEMIBALLISM Clinical Feature Lesion: Subthalamic Nucleus - Usually results from CVA (Cerebrovascular Accident) involving subthalamic nucleus - sudden onset - Violent, writhing, involuntary movements of wide excursion confined to one half of the body - The movements are continuous and often exhausting but cease during sleep - Sometimes fatal due to exhaustion - Could be controlled by phenothiazines and stereotaxic surgery Parkinson’s Disease PD Disease of mesostriatal dopaminergic system Muhammad Ali in Alanta Olympic normal Parkinson’s Disease - Paralysis Agitans Substantia Nigra, Pars Compacta (SNc) DOPAminergic Neuron Clinical Feature (1) Slowness of Movement - Difficulty in Initiation and Cessation of Movement Parkinson’s Disease Paralysis Agitans Clinical Feature (2) Resting Tremor Parkinsonian Posture Rigidity-Cogwheel Rigidity