Med CHEM

• Cardiac Glycosides


  • Dig
  • Digitalis
  • Digoxin
• Cardiac Glycosides


  1. Inhibits

  2. Increases contractility in CHF

  3. Increases refractory period of AVN conduction

  4. Decreases heart rate in arrhythmias
• Cardiac Glycosides


  • Palpitation
  • Tachycardia
• Diuretics


  • Increase contractility
  • Increase solute excretion of Na, Cl
  • Increase urine volume
  • Decrease osmotic pressure in renal tubule
  • Decrease blood volume
• Carbonic anhydrase inhibitors


  • Acetazolamide
  • Inhibit proximal convoluted tubule
  • Inhibit proximal straight tubule counter transport
• Osmotic diuretics


  • Mannitol
  • Inhibit not, HCO3 and Cl counter transport
  • Increase pressure in thin descending limb, proximal convoluted tubule, distal convoluted tubule, collecting duct
• Loop diuretics


  • Ethacrynic acid, Furosemide
  • Inhibit Na+-K-2Cl cotransporters in thick ascending limb
• Thiazide diuretics


  • Hydrochlorothiazide
  • Inhibit Na-Cl cotransporter in distal convoluted tubule
  • Decrease reabsorption of water and electrolytes
• Potassium-sparing diuretics


  • Spironolactone, Amiloride
  • Reduce K+ loss by inhibiting Na+/K+ exchange in cortical collecting tubule
• Anesthesia


  A reversible condition induced by anesthetic drugs that cause reduction or complete loss of response to pain or another sensation such as consciousness and muscle movements during surgery or other invasive procedures
• Types of anesthesia


  • General anesthesia
  • Local anesthesia
• General anesthesia


  Makes the whole body lose feeling, movement and consciousness
• Local anesthesia


  Numbs only a specific targeted area of the body
• Stages of general anesthesia

  1. Induction

  2. Excitement

  3. Surgical anesthesia

  4. Medullary paralysis or overdose
• Induction


  Period during which the patient goes from state of consciousness to a state of unconsciousness
• Excitement


  Depression of inhibitory neurons in the CNS leads to increased excitement, involuntary muscle movement, increased heart rate, blood pressure and respiration
• Surgical anesthesia


  Gradual loss of muscle tone and reflexes, patient is fully unconscious, unresponsive to surgery and has regular breathing
• Medullary paralysis or overdose


  Respiratory and cardiovascular failure occurs which lead to death if the patient cannot be revived quickly
• General anesthetics


  • Multiple sites and different mechanisms are most likely responsible for their effects
  • Action on thalamus and reticular activating system leads to reversible loss of consciousness
  • Action on the hippocampus, amygdala and prefrontal cortex causes amnesia
  • Action on the spinal cord is responsible for immobility and analgesia
• Groups of general anesthetics

  • Intravenous agents (Etomidate, Propofol, Barbiturates)
  • Intravenous agent (Ketamine) and inhalation agents (Nitrous Oxide, Xenon, Cyclopropane)
  • Halogenated volatile anesthetics (Halothane, Enflurane, Isoflurane, Sevoflurane, Desflurane)
• Group 1 general anesthetics

  Much more potent at producing unconsciousness rather than immobility or analgesia, commonly used in the induction phase, effects mediated by GABA-A receptors
• Group 2 general anesthetics


  Produce significant analgesia but relatively weak ability to produce unconsciousness and immobility, typically used in the maintenance phase, effects mediated by NMDA receptors and 2-pore-domain potassium channels
• Group 3 general anesthetics

  More potent at producing immobility, diverse mechanism of action including effects on GABA-A receptors, NMDA receptors, and various ion channels
• Dexmedetomidine


  Unique ability to produce sedation and analgesia without the risk of respiratory depression, acts on presynaptic alpha-2 adrenergic receptors
• Local anesthetics


  Produce transient loss of sensory perception, especially of pain, in a localized area of the body without producing unconsciousness, work by binding to voltage-gated sodium channels and preventing sodium influx
• When used properly, local anesthetics are generally very safe and serious reactions are rare, but systemic toxicity can cause symptoms ranging from blurry vision and lightheadedness to seizures and cardiac arrhythmias
• Cardiac muscle is found only in the heart and allows involuntary contraction.
• Skeletal muscles are attached to bones by tendons and allow voluntary movement.
• The three main types of muscle tissue are skeletal, cardiac, and smooth.
• Glucose, amino acids and vitamins are actively transported back into the blood by the proximal convoluted tubule
• Muscle tissue has three types of fibers: slow twitch (Type I), fast twitch oxidative glycolytic (Type IIa), and fast twitch glycolytic (Type IIb).
• Slow twitch (Type I) fibers have high endurance capacity and use aerobic metabolism.
• Fast twitch oxidative glycolytic (Type IIa) fibers have moderate endurance capacity and use both aerobic and anaerobic metabolism.
• Myosin filaments slide along actin filaments during muscle contractions.
• Aldosterone stimulates Na+ reabsorption and K+ secretion in the distal convoluted tubule and collecting duct
• Antidiuretic hormone (ADH) increases water permeability in the collecting duct, leading to increased water reabsorption and decreased urine output
• Atrial natriuretic peptide (ANP) inhibits Na+ reabsorption in the kidney, resulting in increased excretion of salt and water
• Fast-twitch oxidative glycolytic fibers have moderate endurance and moderate power output, while fast-twitch glycolytic fibers have poor endurance and high power output.
• Fast twitch oxidative glycolytic (Type IIa) fibers have moderate endurance capacity and can switch between aerobic and anaerobic metabolism.
• Amino acid reabsorption occurs through active transport mechanisms such as sodium-dependent cotransport or secondary active transport using Na+/K+-ATPase.