Primary Receptors Flashcards
1
Q
Cholinergic Receptors
A
mediate responses to acetylcholine (ACh)
2
Q
Adrenergic receptors
A
mediate responses to epinephrine (Epi) (adrenaline) and norepinephrine (NE)
3
Q
major subtypes of cholinergic receptors
A
- nicotinic - N
- nicotinic - M
- Muscarinic
4
Q
nicotinic effects on skeletal and ciliary muscles
A
- skeletal muscles contract thus these have receptors in which nicotine can act
- ciliary muscles do not respond - these do not have receptors for nicotine
- nicotine mimics the effects of ACh on skeletal muscles, nicotine acts at the same receptors where ACh acts
- both skeletal and ciliary muscles have receptors for ACh and nicotine appears to act only at the ACh receptors on skeletal muscles, can conclude that ACh receptors on skeletal muscles are different than ACh on ciliary muscles
5
Q
muscarinic responses on skeletal and ciliary muscles
A
- ciliary muscles have receptors that respond to muscarine
- skeletal muscles may not have receptors to muscarine
- muscarine may act at the same receptors on ciliary muscles where ACh acts
- the receptors for ACh on ciliary muscles may be different from receptors for ACh on skeletal muscles
6
Q
activation of nicontinicN receptors promotes
A
ganglionic transmission at all ganglia of the SNS and PNS
Also - releases epinephrine from adrenal medulla
7
Q
activation of nicontinicM receptors promotes
A
conraction of the skeletal muscles
8
Q
activation of muscarinic receptors promotes
A
located on target organs of the PNS elicits response from organ involved
- increased glandular secretions - pulmonary, gastric, intestinal, sweat glands
- contraction of smooth muscles in bronchi and GI tract
- slowing of heart rate
- contraction of sphincter muscles in the iris - miosis
- contraction of ciliary muscles of the eye - lens to focus for near vision
- dilation of blood vessels
- voiding of bladder and relaxation of sphincter muscle
