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Body fluid compartments
Movement of water between body compartments
Acid-base disturbances: Pathology review
Diabetes insipidus and SIADH: Pathology review
Electrolyte disturbances: Pathology review
Renal failure: Pathology review
Acyanotic congenital heart defects: Pathology review
Adrenal masses: Pathology review
Bacterial and viral skin infections: Pathology review
Bone tumors: Pathology review
Coagulation disorders: Pathology review
Congenital neurological disorders: Pathology review
Cyanotic congenital heart defects: Pathology review
Extrinsic hemolytic normocytic anemia: Pathology review
Eye conditions: Inflammation, infections and trauma: Pathology review
Eye conditions: Refractive errors, lens disorders and glaucoma: Pathology review
Headaches: Pathology review
Intrinsic hemolytic normocytic anemia: Pathology review
Leukemias: Pathology review
Lymphomas: Pathology review
Macrocytic anemia: Pathology review
Microcytic anemia: Pathology review
Mixed platelet and coagulation disorders: Pathology review
Nasal, oral and pharyngeal diseases: Pathology review
Nephritic syndromes: Pathology review
Nephrotic syndromes: Pathology review
Non-hemolytic normocytic anemia: Pathology review
Pediatric brain tumors: Pathology review
Pediatric musculoskeletal disorders: Pathology review
Platelet disorders: Pathology review
Renal and urinary tract masses: Pathology review
Seizures: Pathology review
Viral exanthems of childhood: Pathology review
Adrenal insufficiency: Pathology review
Central nervous system infections: Pathology review
Childhood and early-onset psychological disorders: Pathology review
Congenital gastrointestinal disorders: Pathology review
Diabetes mellitus: Pathology review
Environmental and chemical toxicities: Pathology review
Gastrointestinal bleeding: Pathology review
GERD, peptic ulcers, gastritis, and stomach cancer: Pathology review
Inflammatory bowel disease: Pathology review
Medication overdoses and toxicities: Pathology review
Obstructive lung diseases: Pathology review
Pneumonia: Pathology review
Psychiatric emergencies: Pathology review
Shock: Pathology review
Supraventricular arrhythmias: Pathology review
Traumatic brain injury: Pathology review
Ventricular arrhythmias: Pathology review
Congenital TORCH infections: Pathology review
Jaundice: Pathology review
Respiratory distress syndrome: Pathology review
Autosomal trisomies: Pathology review
Cystic fibrosis: Pathology review
Disorders of sex chromosomes: Pathology review
HIV and AIDS: Pathology review
Miscellaneous genetic disorders: Pathology review
Papulosquamous and inflammatory skin disorders: Pathology review
Anxiety disorders, phobias and stress-related disorders: Pathology Review
Developmental and learning disorders: Pathology review
Eating disorders: Pathology review
Mood disorders: Pathology review
Pharmacodynamics: Agonist, partial agonist and antagonist
Pharmacodynamics: Desensitization and tolerance
Pharmacodynamics: Drug-receptor interactions
Pharmacokinetics: Drug absorption and distribution
Pharmacokinetics: Drug elimination and clearance
Pharmacokinetics: Drug metabolism
Androgens and antiandrogens
Estrogens and antiestrogens
Miscellaneous cell wall synthesis inhibitors
Protein synthesis inhibitors: Tetracyclines
Cell wall synthesis inhibitors: Penicillins
Antihistamines for allergies
Non-steroidal anti-inflammatory drugs
Antimetabolites: Sulfonamides and trimethoprim
Cell wall synthesis inhibitors: Cephalosporins
DNA synthesis inhibitors: Fluoroquinolones
DNA synthesis inhibitors: Metronidazole
Miscellaneous protein synthesis inhibitors
Protein synthesis inhibitors: Aminoglycosides
Bronchodilators: Beta 2-agonists and muscarinic antagonists
Bronchodilators: Leukotriene antagonists and methylxanthines
Pulmonary corticosteroids and mast cell inhibitors
Anticonvulsants and anxiolytics: Barbiturates
Anticonvulsants and anxiolytics: Benzodiazepines
Valproic Acid (Valproate) Side Effects
Vigabatrin and Tiagabine
Carbamazepine, phenytoin, gabapentin, tiagabine, vigabatrin
Class I A-C
Anticonvulsants are a type of medication used to treat the various types of seizure disorders.
These include benzodiazepines and barbiturates which increase the activity of inhibitory neurons, but there are also many other classes of anticonvulsants with different mechanisms that we’ll talk about in this video.
Okay, so the cells that make up our brain are called neurons.
Neurons communicate with each other through neurotransmitters.
When one neuron is stimulated, it releases excitatory neurotransmitters that bind to receptors on the next neuron. This causes the next neuron to depolarize and release its own excitatory neurotransmitters, propagating the signal throughout the brain.
The main excitatory neurotransmitter in our brain is glutamate which can bind to several types of receptors that are basically ligand-gated ion channels, which open up and allow Na+ and Ca2+ to flow in, and K+ to flow out.
In the end, when it’s all added up, there’s an influx of positive charge that makes the cell less negative,and the neuron becomes depolarized. This causes nearby voltage-gated Na+ channels to open on the surface of the membrane, causing more Na+ to enter. This in turn triggers other nearby voltage-gated Na+ channels to open.
So this series of depolarization travels down the neuron like a wave and it’s called an action potential.
When it reaches the end of the neuron, called the synaptic terminal, it triggers the opening of voltage-gated Ca2+ channels, causing an influx of calcium ions which stimulates the release of neurotransmitters that are stored in synaptic vesicles.
Okay, we also have inhibitory neurons that shut down this chain of events.
These neurons release the main inhibitory neurotransmitter called gamma-aminobutyric acid or GABA, which binds to GABA receptors on other neurons.
These GABA receptors are also ligand-gated ion channels, but they open up to let the negatively charged Cl-, into the cell.
The influx of negative ions causes hyperpolarization where the cell’s membrane potential becomes more negative, which means it’s much more difficult for it to depolarize and fire off an action potential.
Alright, now there are cases where neurons in the brain start sending out more excitatory signals than normal. This can occur due to either too much excitation or too little inhibition in the brain.
Excessive excitatory signals can cause a variety of disorders like seizures and epilepsy.
Seizures are categorized based on the region of the brain that’s affected.
When it’s limited to one hemisphere or a single lobe, we call it a focal or partial seizure, and these can cause the person to experience strange sensations, like hearing or tasting something that isn’t there, but can also involve jerking movements in specific muscle groups if the neurons controlling these muscles are affected.
Nonbenzodiazepine anticonvulsants are a class of drugs used to treat seizures, headaches, and neuropathic pain. These drugs are also used as mood stabilizers for bipolar disorders. Nonbenzodiazepine anticonvulsants decrease excitatory signals in the brain, primarily by blocking sodium and calcium channels, or by enhancing the actions of GABA. This lead to a decrease in the abnormal electrical activity in the brain responsible for the associated symptoms.
Common examples of nonbenzodiazepine anticonvulsants include carbamazepine, lamotrigine, and valproic acid. Side effects include double vision, ataxia, and liver toxicity for carbamazepine; Stevens Johnson syndrome for lamotrigine; and teratogenic effects like neural tube defects for valproic acid.
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