Brain and Spinal Cord Anatomy PDF

LO1: Contrast the relative position of gray matter and white matter in the brain with the corresponding arrangement of gray and white matter in the spinal cord...

LO1: Contrast the relative position of gray matter and white matter in the brain with the corresponding arrangement of gray and white matter in the spinal cord The color comes from a high lipid fat content in myelin 60% of the brain 40% of the brain Bundles of axons connects hemispheres Latin for “tough body” Cell bodies Dendrites Synapses ©Beatriz Castro  BRAIN vs SPINAL CORD Structures of the CNS and PNS ©Beatriz Castro CNS PNS Group of neuron Cell Bodies (gray matter) Nucleus/ Nuclei Ganglion/ Ganglia Bundle of Axons (white matter) Tract Nerve  LO2: Identify the meninges (in order), their function, and the spaces between them. Meninges: 3 membranes surrounding brain and spinal cord Functions: Protection / structural framework for arteries and veins / CSF circulation scalp cranium Periosteal dura mater -Equivalent to periosteum Superior sagittal sinus Meningeal dura mater Subdural Space Arachnoid mater Subarachnoid Space - Filled with CSF - All cerebral arteries and veins are located here Pia mater - Very thin mb. Follows all contours of brain and arteries. ©Beatriz Castro Cerebral cortex  LO3: Describe the functions of the cerebrospinal fluid (CSF), as well as the details of its production, its circulation within the CNS, and its ultimate reabsorption into the bloodstream. Ventricles: Interconnected cavities inside the brain (4) filled with the CSF CHOROID PLEXUS Produces CSF (from blood plasma) Located in each ventricle ©Beatriz Castro Clear, colorless liquid. CSF functions to protect, nourish, and maintain the optimal environment for the CNS, including cushioning, and waste removal, The Noted Anatomist  LO3 CSF PRODUCTION filtration of blood plasma through capillaries of the brain spongy mass of blood capillaries on the floor or wall of each ventricle modify the filtrate Figure from https://doi.org/10.1152/physrev.00004.2013 ©Beatriz Castro  LO3 CSF CIRCULATION 2 1 Or 4 Interventricular foramen Or aqueduct of Sylvius 3 5 ©Beatriz Castro  LO3 CSF Returns to the Venous System: dural (venous) sinuses- collecting pools of blood, which drain venous blood circulating from the cranial cavity (returns deoxygenated blood from the head to the heart) one of several endothelial-lined spaces in the brain known collectively as cluster of arachnoid membrane https://doi.org/10.1016/B978-0-12-819509-3.00016-X invaginated into the dural sinuses through which CSF enters the venous system. Dura mater ©Beatriz Castro ©The Noted Anatomist By Mikael Häggström, https://commons.wikimedia.org/w/index.php?curid=114156192  LO4: Describe the structural basis for, and the importance of the blood brain barrier (BBB) BLOOD BRAIN BARRIER It comprises the lining of microvessels (capillaries). It is present almost everywhere in the brain. It regulates what substances can get from the bloodstream into the brain's extracellular fluid (Selectively permeable) Generally, only lipid soluble (lipophilic) molecules with a low molecular weight and of positive charge can cross the BBB. Other molecules require transport systems. ©Beatriz Castro There are places called circumventricular organs (CVOs) in the 3rd and 4th ventricles where the barrier is absent, and the blood has direct access to brain neurons. Hladky, S.B., Barrand, M.A. Fluid and ion transfer across the blood–brain and blood–cerebrospinal fluid barriers; a comparative account of mechanisms and roles. Fluids Barriers CNS 13, 19 (2016). https://doi.org/10.1186/s12987-016-0040-3  Capillaries of the choroid plexus Blood capillaries throughout the brain tissue tight junctions between the ependymal cells end-feet perivascular cells that wrap around blood capillaries (peri, around; cyte, cell) ©Beatriz Castro LO4 LO5: Describe the Blood-CSF Barrier NIH Image Gallery