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Flashcards in Nicotinic Receptors Deck (14):
1

Where are nicotinic receptors found?

Gangli + nmj (they're different)

2

Nicotinic receptor general characteristics

Pentamer with integral ion channel

3

Drugs affecting ganglia don't discriminate between ____ + __________

Sympathetic + parasympathetic ganglia

4

Characteristics of nicotine including effects at small and large doses

1. Stable, volatile tertiary amine
2. Readily absorbed through mucous membranes + skin
3. Stimulates ganglia in small doses
4. Blocks ganglia at larger doses

5

Main acute effects of absorbing nicotine by smoking

1. CNS stimulant effects
2. Increased parasympathetic and sympathetic activity
3. Release of ADH of posterior pituitary gland

6

In what ways is parasympathetic and sympathetic activity increased by smoking?

1. Rise BP
2. Tachycardia
3. GI motility inhibitied
4. Increased salivation + bronchial secretion
5. Vasoconstriction (impairment in foetal growth?, increase in cardiovascular disease?)

7

If smoking doesn't cause ganglionic block, what can?

Chewing tobacco

8

How do ganglion-blocking drugs act?

1. On postsynaptic receptor, either as competitive antagonists/ open channel blockers/ mixture of both
2. Selective for autonomic ganglia
3. Don't affect neuromuscular transmission
4. Don't distinguish between sympathetic + parasympathetic action

9

Effects of cardiovascular system block

Depends mainly on sympathetic system
-> dilation of arterioles + veins + loss of cardiovascular reflexes
-:> skin vasodilation

10

Effects of GI block

Mainly parasympathetic
- inhibition of motility and secretion -> constipation (severe)

11

Effects of genito-urinary system block

Parasympathetic block -> impairment of micturition + erection failure
Sympathetic block -> inhibits ejaculation -> impotence

12

Effects of eye block

Loss oc accommodation + pupillary reflex -> photophobia

13

Hexamethonium use

No longer used in man but first effective antihypertensive 1949 - too many side effects

14

Trimetaphan

Produce controlled hypotension during surgery occasionally