Neuronal Physiology

I. Characteristics of the Action Potential (A.P.) A. Ionic Basis and Definition B. Threshold 1. Th = 15%T C. All-or-None 1. Single A.P. vs. Compound A.P. 2. Concept of Recruitment D. Propagation/Conduction Velocity 1. Polarization 2. Local Circuits/Electrotonic Potentials vs. the A.P. 3. Length Constant (Lambda) 4. Myelination vs. Increasing Axon Diameter a. Anatomy 1. Schwann cells (PNS) 2. Oligodendrocytes (CNS) 3. Nodes a. Clustering of Ion Channels 4. Internodes a. 100 layers of Plasma Membrane (Myelin Sheath) b. High Rm b. Saltatory Conduction c. Physiological Benefits of Myelin d. Clinical Aspects of Myelin 1. Damaged Myelin a. Multiple Sclerosis b. Lead/Tin Poisoning c. Household Cleaners 2. Regeneration of PNS axons E. Non-decrementing F. Axon Hillock/Site of Initiation II. Synaptic Transmission A. Introductory 1. Definition of the Synapse 2. Types of Synapses a. Electrical (gap junctions) b. Chemical (synaptic cleft) B. Gap Junctions 1. Basic Properties 2. Protein Structure 3. Where Utilized in the Body C. Synaptic Cleft 1. Otto Loewi's Vagustoff 1921 2. Anatomy a. presynaptic terminal b. vessicles containing NT c. synaptic cleft d. postsynaptic terminal e. use of exocytosis, simple diffusion, ligand-gated ion channels 3. Basic Properties 4. The Neuromuscular Junction (NMJ) a. ACh (acetyl choline) is the NT b. Transport of NT via microtubules and molecular motors c. Role of Na/K ATPase pump d. Role of voltage-dep. Ca channels e. Synapsin, Synaptic Densities, and Release f. How to stop chemical signalling? 1. simple diffusion 2. active reuptake 3. enzymatic breakdown g. EPP= end plate potentials 5. Neural Poisons, Drugs, and Inhibitors of the NMJ a. Blockers of Na channels 1. TTX b. Presynaptic Poisons 1. botulinus 2. procaine c. Postsynaptic Poisons 1. atropine 2. curare 3. TTX 4. alpha BT 5. nicotine d. Inhibitors of AChE (Acetylcholine esterase) 1. strychine 2. nerve gas 3. picrotoxin 4. caffeine 5. theophylline/theobromine 6. parathion/malathion e. Inhibitors of Reuptake 1. Cocaine 6. Neural-Neural Junctions (NNJ) a. Catecholamines: example will demonstrate is norepinephrine (adrenalin) b. Contrasts/Similarities with the NMJ c. Types of Neural Effects 1. Short-term (A.P.) 2. Intermediate (Energy) 3. Long-term (Protein Synthesis) D. Neurotransmitters of the CNS: Imbalances Can Cause Disease - Diversity Required for Complex CNS Functions - 1. Amines 2. Catecholamines 3. Amino Acids (AA) 4. Polypeptides E. Synaptic Involvement in Disease 1. Myasthenia gravis 2. Alzheimer's disease III. Neural Integration A. Types of Input-Output Relations 1. one-to-one synapse 2. one-to-many synapse 3. many-to-one synapse B. Concept of Integration 1. Definitions a. EPSP = excitatory postsynaptic potentials b. IPSP = inhibitory postsynaptic potentials c. classes of contacts 1. axo-axonic 2. axo-dendritic 3. axo-somatic C. Integration in Learning and Memory 1. Facilitation 2. Post-tetanic Stimulation 3. Long-term Potentiation (LTP) 4. Synaptic Fatigue.... WHY YOU SHOULD PRACTICE INTERMITTENT STUDYING!!!!