PS+S receptors and effects Flashcards
Eye: sympathetic stimulation
- Alpha 1: Dilate pupils by contraction of radial muscle, iris
- Beta 2: relaxation of ciliary muscle (low levels unless large stimulation)
o So can focus on distance!
Eye: parasympathetic stimulation
- M3,M2: pupillary constriction by contraction of sphincter muscle, iris
- M3, M2: contraction of ciliary muscle
o So can focus on ‘food’ in front of you (close vision)
Glands of head: sympathetic stimulation
- Alpha 1:
o Lacrimal: increased secretion (‘dry’ secretion)
o salivary: minor increased secretion (dry thick)
Glands of head: parasympathetic stimulation
- M3
Lungs: sympathetic stimulation
- Beta2: bronchiolar dilation by bronchiolar smooth muscle relaxation
- *only if it is a REALLY BIG sympathetic stimulation
Lungs: parasympathetic stimulation
- M3: bronchiolar contraction by contraction of bronchiolar smooth muscle
o Don’t need to be breathing as much
Heart: sympathetic stimulation
- Beta-1>beta-2
o SA node=increased HR
o Atria=increased contractility
o AV node=increased conduction
o Ventricle=increased contractility - *pacemakers and throughout! (effects HR and contractility readily)
Heart: parasympathetic stimulation
- M3
o SA node=decreased HR
o Atria=decreased contractility
o AV node=decreased conduction
o Ventricle=decreased contractility - *mostly to pacemakers (not much to myocardium, primarily see HR effect)
Chronotropic
- Increased HR
Inotropic
- Increased contractility
Dromotropic
- Increased conduction/speed
o Purkinje and AV nodes
Lusotropic
- Increased relaxation
Blood vessels (arteries and arterioles): low sympathetic stimulation (not much E released)
*only see alpha1 effects=constriction
- Coronary
- Pulmonary
- Skin and mucosa (no beta2)
- Skeletal muscle
- Abdominal viscera
Blood vessels (arteries and arterioles): high sympathetic stimulation
*stimulation of adrenals and increased E=alpha 1, but more beta2 =dilation
- Coronary
- Pulmonary
- Skeletal muscle
- Abdominal viscera
- (no beta2 in skin and mucosa)
Blood vessels (arteries and arterioles): parasympathetic stimulation
- *dilation NOT due to PS stimulation
- Only if give a drug and M2 is activated
GI tract: sympathetic stimulation
- Alpha 2
o Decreased motility
o Inhibition of secretion - Alpha 1
o Increased tone of sphincters
GI tract: parasympathetic stimulation
- M3
o Increased motility
o Decreased tone of sphincters
o Increased stimulation
Urinary bladder: sympathetic stimulation
- Beta 2
o Relaxation of detrusor muscle (wall of bladder) =less likely to squeeze out pee - Alpha 1
o Contraction of sphincters
Urinary bladder: parasympathetic stimulation
- M3
o Increased contraction of detrusor muscle (wall of bladder)
o Relaxation of sphincters
Sex organs: sympathetic stimulation
- Alpah1 (male)
o Ejaculation - None in female
Sex organs: parasympathetic stimulation
- M3
o Erection in male and female
Skin: sympathetic stimulation
- Alpha 1
o Sweat glands
o Pilomotor muscles - horses =beta2!
Adrenal medulla: sympathetic stimulation
- Secretion of E from nicotinic receptors
Kidney: sympathetic stimulation
- Beta 1
o Increase renin secretion
