Peripheral Circulation - Neural Flashcards
What is the Sympathetic postganglionic neurotransmitter?
NE - which binds the Beta1 adrenergic receptors
Where are Parasympathetic Preganglionic fibers located?
In the Vagus Nerve
Where are the Parasympathetic Postganglionic Fibers located?
In the Heart.
The Right Side Vagus Nerves innervated what?
parasympathetic
The SA node
The Left Side Vagus Nerve innervated what?
Parasympathetic
The AV node
What is the Parasympathetic Postganglionic Neruotransmitter?
Acetylcholine (ACh) - which bind muscarinic receptors in Cardiac Cell membranes
The Postganglionic Sympathetic Fibers innervated what blood vessels?
Arteries, Arterioles, and Veins
What Receptor does NE bind in Vascular Smooth muscle?
NE binds Alpha1 adrenergic receptors on Vascular smooth muscle and cause constriction
What controls the Strength/Degree of Constriction of vessels?
The Frequency of the impulses/action potentials
What does NE bind Apha1 adrenergic receptors in Vascular smooth muscle (i.e. Veins)?
Because Veins have much less Endothelial cells than Arterioles, so the Alpha1 receptors are there to help control constriction and dilate of veins.
What happens when Veins are constricted?
1) decrease in Diameter
2) decrease in Compliance
3) increased Venous Return
4) increased CO
Arterial Baroreceptor Reflex -
It functions in the rapid, short term regulation of Arterial Blood Pressure
What is the most important organ in the long term regulation of Arterial Blood Pressure?
The kidneys!!!!
What are Baroreceptors?
They are sensors that respond to changes in length (stretch) of the vessel wall.
Postganglionic Sympathetic Fibers: Where are they located and what is their function?
Fibers on the Left Side of the Heart: Affect Contractility
Fibers on the Right Side of the Heart: Affect Heart Rate (SA node)
What are the major functions of Baroreceptors?
They function as short term regulators of BP, for they systolic and diastolic phases of the cardiac cycle.
What is Pressor?
Increased BP
What is Depressor?
Decreased BP
What happens to the Pressor Center is inhibited by Baroreceptor Afferent Impulses?
Vasodilation occurs
What Medullary Regions are part of the Parasympathetic and Sympathetic Nervous system?
Parasympathetic: Pressor Center
Sympathetic: Depressor Center
Where are cardiopulmonary Baroreceptors located?
In the Atria, Ventricles, and Pulmonary vessels
What does Renin do?
It causes Vasoconstriction
What does Vasopressin (Antidiuretic Hormone “ADH”) do?
Increases water reabsorption in kidneys,
Increases Resistance
Increases BP
Peripheral Chemoreceptors predominantly affect what?
They predominantly affect HR
