Neurotransmitter Chemistry of the Autonomic nervous system
- Colinergic Transmission
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Katzungs Basic & Clinical Pharmacology. 12th edition
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- Adrenergic Transmission
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Katzungs Basic & Clinical Pharmacology. 12th edition
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Autonomic receptors
Katzungs Basic & Clinical Pharmacology. 12th edition
Pharmacology of the eye
| Effector | Cholinometic | Anticholinergic |
Sympathetic |
| Pupillary constrictor | contraction | inhibition | |
| Pupillary dilator | Contraction(alpha) | ||
| Ciliary muscle | Contraction(accomodation), | inhibition | |
| Aq secretion | increase out flow of aq humour–> lower intraocular pressure | Decreased production of aq humour –> decreased intraocular pressure?? |
Direct-acting cholinergics (nicotinic / muscarinic).
- Organophosphates
- Miosis
- Ciliary muscle contraction
- Bradycardia
- Negative inotrope
- Slows conduction
- Vasodilation
- Bronchoconstriction
- Increased secretion – GI, bronchial, salivary, sweat, lacrimal
- Increased GI motility
- Sphincters relaxed
- Detruser contraction
Indirect-acting cholinergics (i.e. Cholinesterase inhibitors).
- Alcohols (Edrophonium).
- Duration of action 5-15mins
- Carbamates (Neostigmine).
- Duration of action 0.5-2hrs
Anticholinergics (Atropine).
- Constipation
- Dry eyes
- Mydriasis
- Loss of accomodation(cycloplegia)
- Dry mouth
- Urinary retention
- Decreased sweating (can be increased if increased sympathetics)
- Tachycardia (brady at low dose, tachy at high dose)
- vasodilation
- Bronchodilation and reduced bronchial secretion.
- Eye effects Lasts longer than other effects.
Viva Questions
- What drugs affect the eye.
- Indirect cholinomimetics
- Organophosphates
- Atropine