Week 21 - Multiple Sclerosis Flashcards
What is unique about the endolymph?
Composition similar to intracellular fluid with high K.
How do perilymph and endolymph drain?
Perilymph drains via venules and middle ear mucosa.
Endolymph is absorbed by the endolymphatic sac.
What is the main role of the utricle and saccule?
Reflex adjustments (head position and body position).
What are the 4 vestibular nuclei and what do they do?
Superior VN - from canals to coordinate eye movements
Medial VN - from utricle and saccule to neck and trunk via medial vestibulospinal tract
Lateral VN - from utricle and saccule to limbs via lateral vestibulospinal tract
Inferior VN - receives input from all components and projects to the cerebellum
Describe the course of the cochlear nerve.
Travels to cochlear nuclei in brainstem, from there to the inferior colliculus, from there to the medial geniculate nucleus of thalamus, from there to auditory cortex in temporal lobe.
Each temporal lobe receives input from both ears.
Which otolithic organs are responsible for which directions?
Saccule = sagittal Utricle = horizontal
What are the different types of pharmacological treatment for MS?
Interferon beta, Glatiramer, Integrin inhibitors, Sphingosine receptor modulators, Fumaric acid esters, CD-52 inhibitors, Immunomodulators (GIFISIC)
What is the MOA of Interferon B in MS?
Many effects, but reduced activation of T-cells and migration across the BBB.
What are the contraindications and side effects of Interferon B?
Liver disease (concerns over hepatotoxicity)
Flu-like illness, fatigue, depression, injection site reactions.
What is the MOA of Glatiramer in MS?
Not well understood, but have immunomodulating effect. Inhibits activation of T-Cells by interfering with antigen presentation. Anti-inflammatory effect mediated by TH2 cells. May facilitate remyelination via neurotrophic factors.
What are the contraindications and side effects of Glatiramer?
None.
Injection site reactions, post-injection reactions, infection (due to immunomodulation), some random chest pain.
What is the MOA of Integrin inhibitors in MS and what is the prototype?
They bind to integrin on lymphocytes, thus preventing them from binding to VCAM in brain endothelium and stops crossing the BBB.
Natalizumab.
What are the contraindications and side effects of integrin inhibitors?
Progressive multifocal leukoencephalopathy (PML), immunocompromised
Could lead to PML, could get hypersensitivity reaction (common with monoclonal Ab therapy).
What is the MOA of sphingosine receptor modulators and what is the prototype?
Sphingosine receptors promote T-cell release from lymph nodes. Modulating them reduces the release of T cells, thus preventing them from getting to the CNS.
Fingolimod.
What are the contraindications and side effects of sphingosine receptor modulators?
Serious infection (immunocompromised), active malignancy (may increase risk of cancer or worsen existing cancers)
Cardio problems (S1P receptors are found on the heart, thus bradycardia and heart block), infection (notably herpes), hepatic (may elevate enzymes), increase malignancy.
