‹#› Embryology /organogenesis/ Development and teratology of nervous system. Repetition: nervous tissue. Embsmall ‹#› 2 Special embryology - questions •Development of neural (ganglionic) crest and its differentiation. •Development of spinal cord. •Development of the brain – differentiation of secondary brain vesicles; brain chambers. •Developmental abnormities of central nerve system. ‹#› 3 http://classconnection.s3.amazonaws.com/391/flashcards/578391/png/untitled1308508383511.png http://www.dynamisch.nu/feno/afbembryoengels/87gastrula3c.jpg NOTOCHORD DEVELOPMENT NOTOCHORD - induction of neural plate development ‹#› 4 1 Neural plate – thickened area of embryonic ectoderm ð neuroectoderm Pharyngeal membrane Primitive streak and node Cloacal membrane Notochord pseudostratif. columnar ep. ‹#› 5 http://biology.kenyon.edu/courses/biol114/Chap14/PEPhelps-neurulation.jpg https://people.creighton.edu/~idc24708/Genes/Behavioral%20Genetics/3-step%20neurulation.png NEURULATION ‹#› 6 1 Invagination of neural plate ð neural folds + neural groove ‹#› 7 Nervový systém - 42 ‹#› 8 Nervový systém - 44 ‹#› 9 1 Neural tube and neural crest Neuroporus ant., post. Neural tube Neural crest ‹#› 10 1 future brain future spinal cord future spinal and autonomic ganglia ‹#› 11 Nervový systém - 43 NEURAL CREST ‹#› 12 neuralcrest.jpg image by musuq Odontoblasts, leptomeningeal cells, ‹#› 13 http://www.biog1105-1106.org/demos/106/unit03/media/neuralcrest.jpg ‹#› 14 SC-XSect Histogenesis of neural tube The wall of neural tube – several cell layers (simple → pseudostratified neural epithelium) Cell proliferation ð 3 layers (zones): Ependymal Mantle Marginal layer (zone) Ependyma Gray matter White matter (in medulla spinalis) (in brain and cerebellum: cells from mantle zone migrate through marginal zone; gray matter coveres white matter) ‹#› 15 Histogenesis of neural tissue Early development of the neural tube Three layers can lines neural tube (the spinal cord and brain stem). Ependymal layer (germinal) – lining of central canal Mantle layer (gray matter) – neuroblasts + spongioblasts give rise to perikarya of neurons and glial cells Marginal layer (white matter) – without neurons, but with axons of neurons and glial cells ependyme gray matter white matter ‹#› 16 Early development of the neural tube ependyme white matter gray matter In brain and cerebellum In brain and cerbellum: mantle layer cells migrate through marginal layer and the gray matter coveres white matter. Some neurons stay in white matter ð nuclei. In spinal cord ‹#› 17 DrwNeurtube Spinal cord development Dorsal horns Ventral horns motor zone sensory zone future white matter future gray matter ‹#› 18 Nervový systém - 49 SPINAL CORD: 1.Ependymal layer (germinal) 2.Mantle layer (gray matter) 3.Marginal layer (white matter) ‹#› 19 http://www.phasmatodea.org/anatphys/jpegs/12-27_EmbrSpinlCrd_1.jpg http://www.brainviews.com/abFiles/DrwNeurtube.jpg ‹#› 20 HumHPD6L ‹#› 21 Nervový systém - 52 Positional changes of spinal cord Vertebrate canal grows more rapidly than spinal cord and caudal end of spinal cord doesn‘t extend the entire length of canal in adult; it terminates at L1 in adults # . the end fo the 2nd month the 5th month new-born child # ‹#› 22 Brain development •Brain develops from cranial part of neural tube •Week 4 – three primary brain vesicles: prosencephalon (forebrain) mesencephalon (midbrain) rhombencephalon (hindbrain) Nervový systém - 45 Occipital http://www.raisingreaders.org/resource/d/75275/.ToddlerwSignAboveHead_LR_small ‹#› 23 3-1-2-5 week 5 5 secondary vesicles: Lamina terminalis Prosencephalon Mesencephalon Rhombencephalon Telencephalon Diencephalon Metencephalon Myelencephalon 1 2 4 1 – ventriculi lat., 2 – ventriculus tertius, 3 – aqueductus cerebri, 4 – ventriculus quartus 3 Optic vesicle Neurohypophysis Epiphysis Cerebellum Pons ‹#› 24 Nervový systém - 46 ‹#› 25 Nervový systém - 54 ‹#› 26 http://www.startsateight.com/wp-content/uploads/2011/05/48_23BrainDevelopment.jpg ‹#› 27 Myelination of nerve fibers Nervová tkáň - 16 Obaly nervových výběžků Myelinani from the 4th prenatal month to the 2nd postnatal year ‹#› 28 CNS malformations •failure neurulation (absence of notochord inductive influence or teratogen influence on neuroectodermal cells) •defects of spinal cord •defects of brain •difficult malformations of CNS are usually connected with skull or spinal column (vertebral) defects. ‹#› 29 Spinal cord malformations •Defects - clefts of vertebral •arches (rarelly bodies) •Menigocele •Menigomyelocele •Menigohydromyelocele • •Myeloschisis – complete cleft of spinal column in the whole length http://www.primehealthchannel.com/wp-content/uploads/2012/06/Neural-tube-defect-Image.jpg spina bifida cystica http://skeletalsystemdev.weebly.com/uploads/7/0/4/3/7043675/7236642_orig.jpg ‹#› 30 http://media.tumblr.com/tumblr_m4ynmmYZdJ1r261r3.jpg 19087 ‹#› 31 Nervový systém - 53 ‹#› 32 Urodynamics FIG01 Examples of external signs of spina bifida: 1) hairy patch, 2) hemangioma, 3) skin appendage, 4) lipomatous mass. 1 2 3 4 ‹#› 33 Brain malformations •Anencephalia (†) (+ myeloschisis) zarte%20seele%201 ‹#› 34 http://escuela.med.puc.cl/paginas/cursos/tercero/patologia/fotos242-248/244.jpg ‹#› 35 Brain malformations • • • • • tcge010 MICROCEPHALIA Final_Microcephaly2 ‹#› 36 Image ‹#› 37 VPS_Shunt HYDROCEPHALUS fig84_1 Roční dívenka z Indie umírá, trpí strašnou chorobou ‹#› 38 microcephalus-and-hydrocephalus ‹#› 39 Nervový systém - 58 Brain and meninges hernia(tion) ‹#› 40 http://neuropathology-web.org/chapter11/images11/11-4l.jpg http://neuropathology-web.org/chapter11/images11/11-2al.jpg ‹#› 41 end ‹#› 42 •Nerve tissue – definition, structure, function and origin. •Microscopic structure of nerve cell, types of neurons. The sheaths of nerve processes. •Synapses – their structure and function. Nerve mediators (neurotransmiters). •Central and peripheral nerve endings. •Neuroglia – classification, cytological character and function. General histology - questions ‹#› 43 Terms •Neuron – perikaryon – axon (= neurite) – dendrite(s) •Nissl bodies = rough ER •Axon hillock •Myeline sheath •Schwann sheath •Mesaxon •Internodium •Node of Ranvier •Neuron – classification •Synapse (presynaptic knobe, synaptic cleft, postsynaptic memrane) •Neurotransmitters • ‹#› 44 Terms •Neuroglia - classification •Oligodendroglia •Astrocytes •Microglia (of Horteg) •Ependyma - tanycytes •Schwann cells •Satelite cells • • • in CNS in PNS ‹#› 45 •Structure of the brain cortex. Cyto- and myeloarchitecture. •Structure of the cerebellum. Synapses of the cerebellum. •Microscopic structure of the spinal cord. •Microscopic structure of ganglia and peripheral nerves. •Ependyma, plexus chorioideus and meninges. Special histology - questions ‹#› 46 Terms •Brain cortex – 6 layers (lamina) •Cajal cells, Martinotti cells, granular and pyramidal cells •Membrana limitans gliae superficialis et profunda (seu perivascularis) •Brain barrier •Cerebellum – 3 layers of cortex (stratum) •Purkinje cells, basket cells, granular cells •Glomeruli cerebellares •Mossy and climbing fibers ‹#› 47 Terms •Dura mater – arachnoidea – pia mater •Endoneurium – perineurium – epineurium •Plexus chorioideus ‹#› 48 end ‹#› 49 Braincase3 ‹#› 50 Fig. 1 (a) A myelinated axon in the peripheral nervous system and (b) its development. Each Schwann cell myelinates a single axon, to which it is directly apposed. During development (anticlockwise) Schwann cells loosely ensheath axons and the myelin sheath grows around the axon to form concentric layers, which become tightly apposed Fig. 1 (a) A myelinated axon in the peripheral nervous system and (b) its development. Each Schwann cell myelinates a single axon, to which it is directly apposed. During development (anticlockwise) Schwann cells loosely ensheath axons and the myelin sheath grows around the axon to form concentric layers, which become tightly apposed ‹#› 51 Fig. 3 Myelination in the central nervous system. A single oligodendrocyte myelinates numerous axons (a) and, in section, concentric layers of myelin are seen to spiral around the axon (b). Myelin sheaths are arranged along axons in segments 1 mm long separated by short nodes, and would appear as large sheets if they were unwrapped from around the axon Fig. 3 Myelination in the central nervous system. A single oligodendrocyte myelinates numerous axons (a) and, in section, concentric layers of myelin are seen to spiral around the axon (b). Myelin sheaths are arranged along axons in segments 1 mm long separated by short nodes, and would appear as large sheets if they were unwrapped from around the axon ‹#› 52 Nervový systém - 47 HISTOGENESIS of NEURAL TUBE ‹#› 53 Nervový systém - 48 ‹#› 54 Nervový systém - 51 ‹#› 55 Nervový systém - 39 Vztah míchy k rostoucí páteři ‹#› 56 http://www.histology-world.com/photoalbum/albums/userpics/normal_Gray640.png http://www.histology-world.com/photoalbum/albums/userpics/normal_Gray641.png roof plate central canal ependymal layer mantle layer marginal layer floor plate ‹#› 57 http://oxfordmedicine.com/doc/10.1093/med/9780195378580.001.0001/graphic005015-inline.gif