Neurodevelopment Flashcards
When is neurulation initiated?
When the mesoderm (notochord) sends a message to the ectoderm
What does the ectoderm divide into (neurulation)?
The neural crest, neural tube, and epidermis.
What is the ventricular zone and what does it give rise to?
Cells in the neural tube; gives rise to oligodendrocytes, neurons, and astrocytes (also contains dividing neuroectodermal cells).
Six signals that play a role during neural induction by modulating gene expression:
Wnt, BMD, shh, retinoic acid, and fibroblast growth factor,
Failure of neural tube closure (caudal and rostral ends) is called?
Caudally: Spinal Bifida; Rostrally: Anencephaly.
Holoprosencephaly?
Disrupted forebrain development
Medulloblastoma?
Childhood tumor.
Significance of folic acid/vitamin A?
Folic acid: given to pregnant women to decrease the incident of neural tube closure defects. Vitamin A: causes tube closure disruption in excess.
Where does the neural crest originate from?
The dorsal most neural tube (cranial to lumbar regions).
What do neural crest cells differentiate into (3)?
Neurons and glia (PNS); neuroendocrine cells in the adrenal medulla; non-neural cells (melanocytes/cartilage and bone (face), outflow tract in the heart).
Hirschprung’s disease?
Defect of migration of neural crest cells to the colon (loss of enteric neurons in the colon)
Three neural crest disorders (not including Hirschprung’s).
Cranial facial disorders, pigment disorders, neurofibromatosis.
Neural tube differentiates into:
Forebrain (prosencephalon), midbrain (mesencephalon), hindbrain (rhombencephalon), caudal tube (spinal cord)
Forebrain (prosencephalon) differentiates into:
Telencephalon (cerebral cortex, hippocampus, basal ganglia, basal forebrain nuclei, olfactory bulb), diencephalon (thalamus, hypothalamus, retina)
Midbrain (mesencephalon) differentiates into:
Superior and inferior colliculi