• rigidity of death
• Ca+ diffuses into skeletal muscles, muscles contract
• oxidative phosphorylation no longer occurs= no ATP
• means detachment step does not occur and muscle stays contracted

• rare autoimmune disorder
• antibodies against acetycholine receptors at neuromuscular junction
• means muscles fatigue easily and progressive weakening of voluntary movements

• binds acetylcholine receptors and blocks action of acetylcholine 

• toxin found in snake venom
• binds postsynaptically to acetylcholine receptors

• prevents exocytotic release of acetylcholine by blocking fusion of synaptic vesicles with the plasma membrane at the synaptic terminal

Muscular Atrophy:

What is it?

What are the causes?

Wasting away of muscles.

Causes:

• disuse
• zero gravity conditions
• myasthenia gravis
• duchenne muscular dystrophy

Duchenne Muscular Dystrophy

What is it?

What causes it?

Hereditary disease.

Mutation of gene for dystrophin.

• Force µ Cross Sectional Area
• Distance Shortened µ Length of Muscle
• Work done = force x distance shortened
  therefore
• work done µ cross-sectional area x length = vol. of muscle

Glial Cell Tumors

Names?

Worse one?

• Astrocytoma
• Glioblastoma- bad, accounts for 60% of all intracranial tumors
• Oliogodendrogliomos

• degeneration of myelin sheath
• interferes with nerve signal transmission

Myelin Sheath

What is it mainly composed of?

What is it formed by?

What are the spaces in between called?

• Phospholipids
• Schwann cells
• Nodes of Ranvier

Tay-Sachs Disease

What is it?

What causes it?

How does it manifest?

• neurolipidosis
• the breakdown of plasma membrane lipids is impaired
• lipids accumulate in neurons, which balloon and then deteriorate

Huntington's Chorea

What part of the brain is affected?

What is the cause?

• Basal ganglia
• triplet of trinucleotide repeat expansion
• GABA-ergic neurons affected at beginning stages

Huntington's Chorea

Symptoms?

Parkinson's Disease

Parts of the brain affected?

basal ganglion affected by:

1. degeneration of dopmaminergic fibers (dopamine) and 
2. degeneration of substantia nigra

Parkinson's Disease

Symptoms?

• tremors when at rest
• muscle rigidity (tone)
• slowness of movements
• difficulty starting movements
• poverty of movement (no facial expression when talking)
• stooped posture
• shuffling walk
• possible dementia

Parkinson's Disease:

Treatment?

• L-dopa injection
• transplantation of fetal dopaminergic tissue
• stem cell transplantation
• gene therapy

Amytrophic Lateral Sclerosis

Common name?

Symptoms?

Cause?

• Lou Gehrig's Disease
• difficulty breathing and swallowing (gagging)
• head drop due to muscle weaknes
• muscle cramps and weakness
• speech problems
• nerve cells waste away and die so they can no longer send messages to muscles

Epilepsy

Cause?

Treatments (3)?

• Neuron Hyperactivity
• Treatment:

Schizophrenia

What is it?

What is the cause?

What are 3 possible treatments?

• marked disturbances in thinking, emotional responses, and behavior
• prefrontal cortex abnormality: possible excess of dopamine and/or glutamate
• Treatment: chlorpomazine, haloperiodal, clozapine

Clinical Depression

Biogenic Amine Hypothesis?

Treatment?

• diminished activity of norepinephrine and seratonin pathways (which drive the limbic system)
• destroy or inhibit the re-uptake of norepinephrine and seratonin

Clinical Anxiety

Cause?

Treatment?

• Deficiency of GABA in amygdala allows for hyperactivity of neurons
• Benzodiazapines:  bind to and increase responsiveness of GABA Receptors to GABA 
• (this enhances effectiveness of GABA and depresses over-activity of neurons in the amygdala)

Cerebrovascular Accident (Stroke)

Cause?

• excitotoxicity of glutamate
• glutamate taken up by astrocytes and synapses

SSRIs

What does it stand for?

Examples?

How does it work?

What does it treat?

• Seratonin Specific Re-uptake Inhibitors
• Zoloft, Prozac
• Inhibits re-uptake of seratonin
• Treats clinical depression

Monoamine Oxidase Inhibitors (MAOIs)

Cocaine

Effects on neurotransmitters?