Blood Stuff

EPO is released in the

kidneys

Myogenic controls

local vascular smooth muscle responds to changes in MAP to keep perfusion constant to avoid damage to tissue

systemic blood pressure

-Pumping action of heart generates blood flow -Pressure results when flow is opposed by resistance

elastic rebound

Arterial walls Stretch during systole Rebound (recoil to original shape) during diastole Keep blood moving during diastole

blood pressure falls

Increase cardiac output Cause peripheral vasoconstriction

respiratory pump

Inhalation and exhalation of the lungs expand and compress veins to return blood to the heart.

Autoregulation

causes immediate, localized homeostatic adjustments to blood flow

Renin

hormone secreted by the kidney; it raises blood pressure by influencing vasoconstriction (narrowing of blood vessels)

Angiotensin 2 causes

-vasoconstriction -aldosterone increase -ADH release -increase thirst

tissue perfusion is affected by

Blood flow, blood pressure, peripheral resistance and blood volume

ADH responds to

Dangerously low blood pressure and circulating angiogestin 2 Reduces water loss at kidneys

MAP and pulse pressure _____ with distance from heart

Decrease

Venous Pressure and Venous Return

Determines the amount of blood arriving at right atrium each minute Low effective pressure in venous system

local vasoconstrictors

Examples: prostaglandins and thromboxanes Released by damaged tissues Constrict precapillary sphincters Affect a single capillary bed

Atrial natriuretic peptide (ANP)

Leads to reduction in blood volume and pressure Strengthens the bodies response to almost drone Promotes the kidneys to excrete more water and sodium Reduces stress on the heart causing vasodilation

resistance depends on

Length of the vessel Diameter vs sold I lagoon and vasoconstriction

Blood pressure can be calculated by

Mean arterial pressure(MAP)

arterial blood pressure

Measure of the pressure exerted by the blood as it flows through the arteries. Maintains bloodflow

Low venous resistance is assisted by:

Muscular pump of peripheral veins (moving)

EPO stimulates

RBC production Increase in blood volume and viscosity

endocrine mechanisms

Releases hormones that enhance short-term adjustments and that direct long-term changes in cardiovascular performance.

carotid sinus

Respond to blood pressure, Carotid Body responds to partial pressures of O2/CO2, supplied by glossopharyngeal nerve

Angiotensin II

Responds to fall in renal blood pressure Stimulates: Aldosterone production ADH production Thirst Cardiac output and peripheral vasoconstriction Enhances blood volume

Erythropoietin (EPO)

Responds to low blood pressure and low oxygen in the blood

Hormones have

Short term or long term effects on cardiovascular regulation

turbulence

Swirling action that disturbs smooth flow of liquid Occurs in heart chambers and great vessels Atherosclerotic plaques cause abnormal turbulence

carotid artery

The major artery that supplies blood to the head and brain.

systolic pressure

The pressure generated by the left ventricle during contraction

Renin starts

a cascade reaction resulting in the production of angiogestin 2

local vasodilators

accelerate blood flow at tissue level -low O2 or high CO2 levels -low pH (acids) -nitric oxide (NO) -high K+ or H+ concentrations -chemicals released by inflammation (histamine) -elevated local temperature

vasomotor center

adjusts blood vessel diameter for blood pressure regulation

pressure is highest in the

aorta

Largest drop off in pressure is at the

arterioles

neural mechanisms adjust

cardiac output and resistance to maintain blood flow

Tissue perfusion

carries O2 and nutrients to tissues and organs Blood flow to the tissues

Chemoreceptors

chemical sensors in the brain and blood vessels that identify changing levels of oxygen and carbon dioxide Detects changes in ph, O2, and CO2 Low oxygen or high CO2 cause increased cardiac output and blood pressure Produces coordinating cardiovascular and respiratory activities

Sympathetic vasoconstruction

constructs the smooth muscle in the walls of veins

Control of vasodilation of skeletal muscle and brain tissue

controlled by the release of nitric oxide

cardioinhibitory center

controls the parasympathetic neurons that slow the heart rate

blood pressure rises

decrease cardiac output Cause peripheral vasodilation

pulse pressure

difference between systolic and diastolic pressure

capillary blood pressure

filters water and small molecules from the plasma

Vascular resistance

friction between blood and blood vessel walls

cardioacceleratory center

increases cardiac output through sympathetic nerves

Cardiovascular centers

monitor arterial blood pressure

renal mechanisms

most potent, but require hours to days to effect pH changes

cardiac center of medulla oblongata

regulates heart's rate and strength of contraction

vasomotor center controlled by

release of norepinephrine

antidiuretic hormone (ADH)

released by the posterior pituitary (neurohypophysis) controls how much fluid leaves the body in the urine and causes reabsorption of water from the kidney tubules

indirect renal mechanism

renin-angiotensin-aldosterone mechanism Drop in blood pressure signals kidney cells to release renin

neural mechanisms

respond quickly to changes at specific sites

arterial blood pressure will rise and fall with

systole and diastole

blood viscosity

thickness of blood

Baroreceptor reflex

uses stretch receptors found within the walls of carotid, aortic, and right atrium

Too much blood causes

vasoconstiction

increase blood pressure

vasoconstriction

decrease in blood pressure

vasodilation

too little blood causes

vasodilation