Direct Effects Of Autonomic Stimulation Flashcards
What is the action of sympathetic activity in the heart?
Increase HR (at SA node) Increase in contractility and conduction velocity (atria) Increase in automaticity and conduction velocity (AV node and His-purkinje system) Increase in contractility, conduction velocity, automaticity and rate of idioventricular pacemakers (ventricle)
The activation of which adrenergic receptor is mostly responsible for the sympathetic action on the heart?
Beta1 > beta2
What is the action of parasympathetic activity on the heart?
Decrease in HR (SA node)
Decrease in contractility and shortened AP duration (atria)
Decrease in conduction velocity; AV block (AV node)
Little effect on His purkinje system
Slight decrease in contractility in ventricles
Which ACh receptor is responsible for the parasympathetic action on the heart?
M2»_space; M3
What is the sympathetic action on blood vessels?
Constriction of arterioles and arteries
Which adrenergic receptor is responsible for the sympathetic action on BVs?
Alpha 1
What is the parasympathetic action on blood vessels?
No parasympathetic innervation
What is the parasympathetic action on the endothelium?
Activation of NO synthase through M3 receptor activation
What is the sympathetic action on the lungs?
Relaxation of tracheal and bronchial SM (beta2) Decreased secretion (alpha1) and increased secretion (beta2) in bronchial glands
What is the parasympathetic action on the lungs?
Contraction of tracheal and bronchial SM
Stimulation of bronchial glands
Which ACh receptors are responsible for the parasympathetic action on the lungs?
Contraction caused by M2=M3
Stimulation of bronchial glands by M3 and M2
What is the sympathetic action on the kidney?
Decrease renin secretion via alpha1 activation
Increased renin secretion via beta1 activation
What is the parasympathetic action on the kidney?
No parasympathetic innervation
