- •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
Nicotinic antagonists (n-cholinoblockers)
Compose of two drug groups: ganglion-blocking drugs and neuromuscular blocking drugs.
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Ganglion-blocking drugs
List of drugs
Azamethonium bromide
Mechanism of action
Noncompetitive blockage of N-cholinoreceptors of autonomic ganglions
Pharmacological effects
Opposite effect if compared to previous topic:
Blockage of N-cholinoreceptors |
Autonomic ganglions |
Dilation of blood vessels
|
Indications
1. Relieving of hypertensive crises:
Azamethonium → dilation of blood vessels (arteries) → decreasing of arterial pressure → relieving of hypertensive crises
2. Relieving of acute pulmonary oedema:
Azamethonium → dilation of blood vessels (veins) → decreasing of venous blood return to the heart → relieving of acute pulmonary oedema
Neuromuscular blocking drugs (myorelaxants)
List of drugs
Non-depolarising blockers: pipecuronium bromide
Depolarising blockers: suxamethonium
Mechanism of action
Competitive blockage of N-cholinoreceptors of skeletal muscles.
Pharmacological effects
Opposite effect if compared to previous topic:
Blockage of N-cholinoreceptors |
Skeletal muscles |
Relaxation |
Indications
1. Relaxation of skeletal muscles during abdominal surgery
- relaxation of vocal ligaments → facilitation of intubation (inserting specific tube to upper airways to allow general anaesthesia)
- relaxation of skeletal muscles of the body → prevention of any motion of patients during surgery
- in more highest dosages these drugs can also relax a diaphragm, that gives the opportunity to apply to the patient artificial ventilation.
Some aspects of physiology. VERY IMPORTANT!!!
Adrenergic synapses (most of them are sympathetic synapses), as any another synapses in the organism, consist of two parts: presynaps and postsynaps. Presynaps releases norepinephrine, which activates α1, α2, β1, β2-adrenoreceptors on the postsynaptic membrane. Thereafter norepinephrine is destroyed by specific enzyme – catechol-O-methyltransferase (COMT), which is located on the postsynaptic membrane.
Norepinephrine produces next effects (see and study the table):
Type of receptors |
Organ |
Effect |
Stimulation of α1- adrenoreceptors |
Eye |
Dilation of pupil (midriasis) |
Blood vessels |
Constriction (due to contraction of smooth muscles of blood vessels) |
|
Stimulation of α2- adrenoreceptors |
Blood vessels |
Constriction (due to contraction of smooth muscles of blood vessels) |
Stimulation of β1- adrenoreceptors |
Heart |
Increasing of heart rate, heart contractility, heart conductance and heart excitability |
Stimulation of β2- adrenoreceptors |
Bronchi |
Dilation (due to relaxation of smooth muscles of bronchi) |
Uterus |
Relaxation (due to relaxation of smooth muscles of uterus) |
|
Mast cells |
Inhibition of degranulation (i.e. inhibition of releasing of histamine from mast cells) |