Come to your rescue when injury occurs. Physical support, repair (reactive gliosis = only time you can see astrocytes w/o GFAP stain), modulate inflammation since brain swelling is bad. Derived from neuroectoderm.
Munchers (phagocytes), derived from mesoderm. With tissue damage, they become large & engorged (ameboid). Little cytoplasm, plus small, irregular nuclei.
Myelinate multiple CNS axons (up to 30 each). Small nuclei & little cytoplasm. Destroyed in MS.
Myelinate 1 PNS axon. Destroyed in Guillain-Barre syndrome. Derived from neural crest cells.
What is Nissl substance, & where is it found?
RER. Found in dendrites & cell bodies of neurons, but not in their axons.
Detect dynamic touch (e.g. manipulation); fast adaptation. Found in hairless (glabrous) skin... so, a massage feels better on your back than your forearms.
Slowly adapting; detect static touch. (Meissner's vs. Merkel's: Merle is old & static.) Found in hair follicles (b/c old men are hairier).
Vibration in pressure. Found in joints, ligaments, deep skin layers.
Neurotransmitter changes with anxiety disorder
Inc'd norepinephrine, dec'd serotonin.
For what conditions does dopamine increase or decrease?
Decrease = Parkinson's; increase = schizophrenia.
For what conditions does ACh decrease?
Locations of BBB where capillaries are fenestrated
Vomiting center (area postrema), OVLT (for osmolarity). Both signal to hypothalamus.
Wernicke-Korsakoff syndrome. Wernicke's encephalopathy = reversible: confusion, ataxia, ophthalmoplegia. Korsakoff's psychosis = irreversible: confabulation due to amnesia -- so you don't know you're making things up.
Middle cerebellar peduncle receives input from
Inferior cerebellar peduncle receives input from
Huntington's disease -- including chromosome
CAG repeats on chromosome 4. Lose GABA neurons from caudate nucleus (makes sense, since caudate = cognitive while putamen = more motor). Depression, dementia, chorea.
Wild flailing of 1 arm. Contralateral subthalamic nucleus lesion --> internal globus pallidus is no longer excited as much --> less tonic inhibition of thalamus.
Cerebellar dysfunction. Zigzag motions when pointing toward a target.
Wallenberg syndrome (including the vessel infarcted)