- •Simplicified version! Drugs Affecting the Afferent Innervation
- •Indications:
- •Indications 3 - 6
- •Indication 1
- •Indication 2
- •Indications:
- •(CholinOnegative drugs)
- •Anticholinesterases
- •Muscarinic agonists (m-cholinomimetics)
- •Nicotinic agonists (n-cholinomimetics)
- •Simplicified version
- •(Cholinonegative drugs)
- •Muscarinic antagonists (m-cholinoblockers)
- •Nicotinic antagonists (n-cholinoblockers)
- •Ganglion-blocking drugs
- •Neuromuscular blocking drugs (myorelaxants)
- •Simplicified version
- •(Adrenopositive drugs)
- •Indirect adrenomimetics
- •Direct adrenomimetics
- •Mixed action Adrenomimetics
- •Alfa-adrenomimetics
- •Beta-adrenomimetics
- •Simplicified version
- •(Adrenonegative drugs)
- •Sympatholytics
- •Alfa-adrenoblockers
- •Beta-adrenoblockers
- •General anesthetics
- •Analgesic drugs
- •Hypnotic drugs
- •Antiepileptic drugs (anticonvulsants)
- •Sedative drugs
- •Anxyolytics (antianxiety drugs, tranquillizers)
- •Antipsychotic drugs (neuroleptics)
- •Analeptics
Beta-adrenoblockers
List of drugs
β1, β2-adrenoblockers: propranolol hydrochloride
β1-adrenoblockers: metoprolol, atenolol, nebivolol
Mechanism of action
Propranolol produces direct blockage of β1, β2-adrenoreceptors.
Metoprolol, atenolol and nebivolol produce direct blockage of β1-adrenoreceptors.
Pharmacological effects:
Previous time you studied the pharmacological effects of Beta-adrenomimetics (see my previous material). For today topic «Beta-adrenoblockers» pharmacological effects will be strongly opposite (see table):
for propranolol:
Type of receptors |
Organ |
Effect |
Blockage of β1- adrenoreceptors |
Heart |
Decreasing of heart rate, heart contractility, heart conductance and heart excitability |
Blockage of β2- adrenoreceptors |
Bronchi |
Constriction (due to contraction of smooth muscles of bronchi) |
for metoprolol, atenolol and nebivolol:
Type of receptors |
Organ |
Effect |
Blockage of β1- adrenoreceptors |
Heart |
Decreasing of heart rate, heart contractility, heart conductance and heart excitability |
Indications
Hypertension (chronic treatment)
Propranolol, metoprolol, atenolol, nebivolol → blockage of β1-adrenoreceptors → decreasing of heart rate and heart contractility → decreasing of arterial pressure.
Tachyarrhythmia (tachycardia)
Propranolol, metoprolol, atenolol, nebivolol → blockage of β1-adrenoreceptors → decreasing of heart rate → inhibition of tachyarrhythmia (tachycardia).
Angina pectoris
Propranolol, metoprolol, atenolol, nebivolol → blockage of β1-adrenoreceptors → decreasing of heart rate and heart contractility → decreasing of heart work → decreasing in oxygen demand for myocardium → decreasing of ischemia of myocardium → decreasing of constricting pain in the chest (angina pectoris).
Side effects:
Propranolol can produce bronchospasm due to blockage of β2- adrenoreceptors.
SIMPLICIFIED VERSION
General anesthetics
List of drugs
Inhalation anesthetics: Diethyl ether, Halothane, Nitrous oxide
Intravenous anesthetics: Thiopental sodium, Ketamine, Sodium oxybate
Mechanism of action
Inhalation anesthetics produce two activities:
change the physicochemical properties of neuronal membranes thus resulting in decrease of excitability of neurons;
potentiate GABAergic inhibition of central nervous system.
The mechanism of action of intravenous anesthetics you should not study.
Pharmacological effects
These drugs induce the inhibition of central nervous system below normal state and produce the general anaesthesia (narcosis).
Indications
General anesthesia is essential to surgical practice, because it renders patients analgesic, amnesic, and unconscious, while causing muscle relaxation and suppression of undesirable reflexes.
Induction to anaesthesia: using of intravenous anesthetics before applying of inhalation anesthetics (Thiopental sodium, intravenous Ketamine).
Basal anaesthesia: using of intravenous anesthetics along with inhalation anesthetics (Thiopental sodium, intramuscular Ketamine, Sodium oxybate)
Mixed anaesthesia: combined using of inhalation anesthetics (e.g. Halothane + Nitrous oxide)
All of these approaches we need to use for decreasing of side effects of narcosis, producing more deeper anaesthesia etc.
Side effects:
Diethyl ether produces the irritative action on the upper respiratory tract (up to respiratory arrest) and on the cardiac system (up to cardiac arrest)
Ketamine can induce the postoperative hallucinations.
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