Mean Mean Mean is the sum of all measurements in a data set divided by the number of measurements in that data set. Measures of Central Tendency and Dispersion arterial pressure (MAP) is the average systemic pressure in the arteries Arteries Arteries are tubular collections of cells that transport oxygenated blood and nutrients from the heart to the tissues of the body. The blood passes through the arteries in order of decreasing luminal diameter, starting in the largest artery (the aorta) and ending in the small arterioles. Arteries are classified into 3 types: large elastic arteries, medium muscular arteries, and small arteries and arterioles. Arteries: Histology. The MAP is tightly regulated to help maintain appropriate perfusion and is primarily determined by the cardiac Cardiac Total Anomalous Pulmonary Venous Return (TAPVR) output (CO) and the systemic vascular resistance Systemic vascular resistance Afterload is the resistance in the aorta that prevents blood from leaving the heart. Afterload represents the pressure the LV needs to overcome to eject blood into the aorta. Cardiac Mechanics (SVR). Cardiac Cardiac Total Anomalous Pulmonary Venous Return (TAPVR) output is determined by the HR and the stroke volume Stroke volume The amount of blood pumped out of the heart per beat, not to be confused with cardiac output (volume/time). It is calculated as the difference between the end-diastolic volume and the end-systolic volume. Cardiac Cycle (the volume of blood ejected by the heart each beat). The HR is primarily regulated by the effects of the ANS ANS The ans is a component of the peripheral nervous system that uses both afferent (sensory) and efferent (effector) neurons, which control the functioning of the internal organs and involuntary processes via connections with the CNS. The ans consists of the sympathetic and parasympathetic nervous systems. Autonomic Nervous System: Anatomy on the sinoatrial node Sinoatrial node The small mass of modified cardiac muscle fibers located at the junction of the superior vena cava and right atrium. Contraction impulses probably start in this node, spread over the atrium (heart atrium) and are then transmitted by the atrioventricular bundle (bundle of His) to the ventricle (heart ventricle). Heart: Anatomy in the heart, while stroke volume Stroke volume The amount of blood pumped out of the heart per beat, not to be confused with cardiac output (volume/time). It is calculated as the difference between the end-diastolic volume and the end-systolic volume. Cardiac Cycle is determined by the preload Preload Cardiac Mechanics, afterload Afterload Afterload is the resistance in the aorta that prevents blood from leaving the heart. Afterload represents the pressure the LV needs to overcome to eject blood into the aorta. Cardiac Mechanics, and inotropy (or contractile strength) of each heartbeat. The SVR is regulated by a number of factors, including the ANS ANS The ans is a component of the peripheral nervous system that uses both afferent (sensory) and efferent (effector) neurons, which control the functioning of the internal organs and involuntary processes via connections with the CNS. The ans consists of the sympathetic and parasympathetic nervous systems. Autonomic Nervous System: Anatomy, the arterial baroreflex Baroreflex A response by the baroreceptors to increased blood pressure. Increased pressure stretches blood vessels which activates the baroreceptors in the vessel walls. The net response of the central nervous system is a reduction of central sympathetic outflow. This reduces blood pressure both by decreasing peripheral vascular resistance and by lowering cardiac output. Because the baroreceptors are tonically active, the baroreflex can compensate rapidly for both increases and decreases in blood pressure. Vascular Resistance, Flow, and Mean Arterial Pressure, circulating catecholamines Catecholamines A general class of ortho-dihydroxyphenylalkylamines derived from tyrosine. Adrenal Hormones, the RAAS RAAS A blood pressure regulating system of interacting components that include renin; angiotensinogen; angiotensin converting enzyme; angiotensin i; angiotensin ii; and angiotensinase. Renin, an enzyme produced in the kidney, acts on angiotensinogen, an alpha-2 globulin produced by the liver, forming angiotensin I. Angiotensin-converting enzyme, contained in the lung, acts on angiotensin I in the plasma converting it to angiotensin II, an extremely powerful vasoconstrictor. Angiotensin II causes contraction of the arteriolar and renal vascular smooth muscle, leading to retention of salt and water in the kidney and increased arterial blood pressure. In addition, angiotensin II stimulates the release of aldosterone from the adrenal cortex, which in turn also increases salt and water retention in the kidney. Angiotensin-converting enzyme also breaks down bradykinin, a powerful vasodilator and component of the kallikrein-kinin system. Adrenal Hormones, and several other hormones Hormones Hormones are messenger molecules that are synthesized in one part of the body and move through the bloodstream to exert specific regulatory effects on another part of the body. Hormones play critical roles in coordinating cellular activities throughout the body in response to the constant changes in both the internal and external environments. Hormones: Overview and Types.
Last updated: 2 May, 2022
Mean Mean Mean is the sum of all measurements in a data set divided by the number of measurements in that data set. Measures of Central Tendency and Dispersion arterial pressure is the average systemic arterial pressure.
Mean
Mean
Mean is the sum of all measurements in a data set divided by the number of measurements in that data set.
Measures of Central Tendency and Dispersion arterial intravascular pressure throughout the
cardiac cycle
Cardiac cycle
The cardiac cycle describes a complete contraction and relaxation of all 4 chambers of the heart during a standard heartbeat. The cardiac cycle includes 7 phases, which together describe the cycle of ventricular filling, isovolumetric contraction, ventricular ejection, and isovolumetric relaxation.
Cardiac Cycle
P: pressure
Mean Mean Mean is the sum of all measurements in a data set divided by the number of measurements in that data set. Measures of Central Tendency and Dispersion arterial pressure is primarily affected by the CO and SVR:
CO = HR x stroke volume Stroke volume The amount of blood pumped out of the heart per beat, not to be confused with cardiac output (volume/time). It is calculated as the difference between the end-diastolic volume and the end-systolic volume. Cardiac Cycle:
Systemic vascular resistance Systemic vascular resistance Afterload is the resistance in the aorta that prevents blood from leaving the heart. Afterload represents the pressure the LV needs to overcome to eject blood into the aorta. Cardiac Mechanics is primarily affected by:
Factors that
affect
Affect
The feeling-tone accompaniment of an idea or mental representation. It is the most direct psychic derivative of instinct and the psychic representative of the various bodily changes by means of which instincts manifest themselves.
Psychiatric Assessment
mean
Mean
Mean is the sum of all measurements in a data set divided by the number of measurements in that data set.
Measures of Central Tendency and Dispersion arterial pressure (MAP).
CO:
cardiac
Cardiac
Total Anomalous Pulmonary Venous Return (TAPVR) output
SVR:
systemic vascular resistance
Systemic vascular resistance
Afterload is the resistance in the aorta that prevents blood from leaving the heart. Afterload represents the pressure the LV needs to overcome to eject blood into the aorta.
Cardiac Mechanics
Sympathetic stimulation increases MAP, which increases both SVR and CO:
Parasympathetic stimulation decreases MAP by decreasing both SVR and CO:
The baroreceptor reflex Baroreceptor reflex A response by the baroreceptors to increased blood pressure. Increased pressure stretches blood vessels which activates the baroreceptors in the vessel walls. The net response of the central nervous system is a reduction of central sympathetic outflow. This reduces blood pressure both by decreasing peripheral vascular resistance and by lowering cardiac output. Because the baroreceptors are tonically active, the baroreflex can compensate rapidly for both increases and decreases in blood pressure. Vascular Resistance, Flow, and Mean Arterial Pressure is the most important mechanism for acute BP regulation.
Locations of the carotid and aortic baroreceptors Baroreceptors Receptors in the vascular system, particularly the aorta and carotid sinus, which are sensitive to stretch of the vessel walls. Diabetes Insipidus
Image by Lecturio.
Baroreceptors
Baroreceptors
Receptors in the vascular system, particularly the aorta and carotid sinus, which are sensitive to stretch of the vessel walls.
Diabetes Insipidus are
neurons
Neurons
The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the nervous system.
Nervous System: Histology that sense the stretching of a blood vessel.
P: pressure
↑ Blood pressure → ↑ vessel stretch → ↑ rate of baroreceptor firing → leads to:
Responses of the
baroreceptor reflex
Baroreceptor reflex
A response by the baroreceptors to increased blood pressure. Increased pressure stretches blood vessels which activates the baroreceptors in the vessel walls. The net response of the central nervous system is a reduction of central sympathetic outflow. This reduces blood pressure both by decreasing peripheral vascular resistance and by lowering cardiac output. Because the baroreceptors are tonically active, the baroreflex can compensate rapidly for both increases and decreases in blood pressure.
Vascular Resistance, Flow, and Mean Arterial Pressure to increased blood pressure:
HR:
heart rate
Heart rate
The number of times the heart ventricles contract per unit of time, usually per minute.
Cardiac Physiology
CO:
cardiac
Cardiac
Total Anomalous Pulmonary Venous Return (TAPVR) output
SVR:
systemic vascular resistance
Systemic vascular resistance
Afterload is the resistance in the aorta that prevents blood from leaving the heart. Afterload represents the pressure the LV needs to overcome to eject blood into the aorta.
Cardiac Mechanics
↓ Blood pressure → ↓ stretch → ↓ rate of baroreceptor firing → leads to:
Responses of the
baroreceptor reflex
Baroreceptor reflex
A response by the baroreceptors to increased blood pressure. Increased pressure stretches blood vessels which activates the baroreceptors in the vessel walls. The net response of the central nervous system is a reduction of central sympathetic outflow. This reduces blood pressure both by decreasing peripheral vascular resistance and by lowering cardiac output. Because the baroreceptors are tonically active, the baroreflex can compensate rapidly for both increases and decreases in blood pressure.
Vascular Resistance, Flow, and Mean Arterial Pressure to decreased blood pressure:
HR:
heart rate
Heart rate
The number of times the heart ventricles contract per unit of time, usually per minute.
Cardiac Physiology
CO:
cardiac
Cardiac
Total Anomalous Pulmonary Venous Return (TAPVR) output
SVR:
systemic vascular resistance
Systemic vascular resistance
Afterload is the resistance in the aorta that prevents blood from leaving the heart. Afterload represents the pressure the LV needs to overcome to eject blood into the aorta.
Cardiac Mechanics
Baroreceptor reflex
Baroreceptor reflex
A response by the baroreceptors to increased blood pressure. Increased pressure stretches blood vessels which activates the baroreceptors in the vessel walls. The net response of the central nervous system is a reduction of central sympathetic outflow. This reduces blood pressure both by decreasing peripheral vascular resistance and by lowering cardiac output. Because the baroreceptors are tonically active, the baroreflex can compensate rapidly for both increases and decreases in blood pressure.
Vascular Resistance, Flow, and Mean Arterial Pressure in response to
hypotension
Hypotension
Hypotension is defined as low blood pressure, specifically < 90/60 mm Hg, and is most commonly a physiologic response. Hypotension may be mild, serious, or life threatening, depending on the cause.
Hypotension:
The decrease in blood pressure is sensed by the aortic
baroreceptors
Baroreceptors
Receptors in the vascular system, particularly the aorta and carotid sinus, which are sensitive to stretch of the vessel walls.
Diabetes Insipidus, which initiate the reflex. The induced sympathetic response causes peripheral arterial
vasoconstriction
Vasoconstriction
The physiological narrowing of blood vessels by contraction of the vascular smooth muscle.
Vascular Resistance, Flow, and Mean Arterial Pressure, increasing
systemic vascular resistance
Systemic vascular resistance
Afterload is the resistance in the aorta that prevents blood from leaving the heart. Afterload represents the pressure the LV needs to overcome to eject blood into the aorta.
Cardiac Mechanics (SVR). Constriction of the
veins
Veins
Veins are tubular collections of cells, which transport deoxygenated blood and waste from the capillary beds back to the heart. Veins are classified into 3 types: small veins/venules, medium veins, and large veins. Each type contains 3 primary layers: tunica intima, tunica media, and tunica adventitia.
Veins: Histology increases
preload
Preload
Cardiac Mechanics, which increases
stroke volume
Stroke volume
The amount of blood pumped out of the heart per beat, not to be confused with cardiac output (volume/time). It is calculated as the difference between the end-diastolic volume and the end-systolic volume.
Cardiac Cycle and thus
cardiac
Cardiac
Total Anomalous Pulmonary Venous Return (TAPVR) output (CO). The sympathetic response also increases HR and
cardiac
Cardiac
Total Anomalous Pulmonary Venous Return (TAPVR) inotropy. These all contribute to normalization of the blood pressure.
MAP:
mean
Mean
Mean is the sum of all measurements in a data set divided by the number of measurements in that data set.
Measures of Central Tendency and Dispersion arterial pressure
Relationship
Relationship
A connection, association, or involvement between 2 or more parties.
Clinician–Patient Relationship between arterial pressure and baroreceptor firing frequency in normotensive and hypertensive
patients
Patients
Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.
Clinician–Patient Relationship:
As arterial pressure increases, the baroreceptor
afferent neurons
Afferent neurons
Neurons which conduct nerve impulses to the central nervous system.
Autonomic Nervous System: Anatomy fire more frequently in a sigmoidal
relationship
Relationship
A connection, association, or involvement between 2 or more parties.
Clinician–Patient Relationship. Chronic
hypertension
Hypertension
Hypertension, or high blood pressure, is a common disease that manifests as elevated systemic arterial pressures. Hypertension is most often asymptomatic and is found incidentally as part of a routine physical examination or during triage for an unrelated medical encounter.
Hypertension decreases the
sensitivity
Sensitivity
Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives.
Blotting Techniques of the
baroreceptors
Baroreceptors
Receptors in the vascular system, particularly the aorta and carotid sinus, which are sensitive to stretch of the vessel walls.
Diabetes Insipidus, shifting the curve to the right.
MAP:
mean
Mean
Mean is the sum of all measurements in a data set divided by the number of measurements in that data set.
Measures of Central Tendency and Dispersion arterial pressure
The RAAS RAAS A blood pressure regulating system of interacting components that include renin; angiotensinogen; angiotensin converting enzyme; angiotensin i; angiotensin ii; and angiotensinase. Renin, an enzyme produced in the kidney, acts on angiotensinogen, an alpha-2 globulin produced by the liver, forming angiotensin I. Angiotensin-converting enzyme, contained in the lung, acts on angiotensin I in the plasma converting it to angiotensin II, an extremely powerful vasoconstrictor. Angiotensin II causes contraction of the arteriolar and renal vascular smooth muscle, leading to retention of salt and water in the kidney and increased arterial blood pressure. In addition, angiotensin II stimulates the release of aldosterone from the adrenal cortex, which in turn also increases salt and water retention in the kidney. Angiotensin-converting enzyme also breaks down bradykinin, a powerful vasodilator and component of the kallikrein-kinin system. Adrenal Hormones is the major long-term regulator of blood pressure.
Factors that stimulate the RAAS RAAS A blood pressure regulating system of interacting components that include renin; angiotensinogen; angiotensin converting enzyme; angiotensin i; angiotensin ii; and angiotensinase. Renin, an enzyme produced in the kidney, acts on angiotensinogen, an alpha-2 globulin produced by the liver, forming angiotensin I. Angiotensin-converting enzyme, contained in the lung, acts on angiotensin I in the plasma converting it to angiotensin II, an extremely powerful vasoconstrictor. Angiotensin II causes contraction of the arteriolar and renal vascular smooth muscle, leading to retention of salt and water in the kidney and increased arterial blood pressure. In addition, angiotensin II stimulates the release of aldosterone from the adrenal cortex, which in turn also increases salt and water retention in the kidney. Angiotensin-converting enzyme also breaks down bradykinin, a powerful vasodilator and component of the kallikrein-kinin system. Adrenal Hormones (i.e., renin Renin A highly specific (leu-leu) endopeptidase that generates angiotensin I from its precursor angiotensinogen, leading to a cascade of reactions which elevate blood pressure and increase sodium retention by the kidney in the renin-angiotensin system. Renal Sodium and Water Regulation secretion Secretion Coagulation Studies) include:
Renin Renin A highly specific (leu-leu) endopeptidase that generates angiotensin I from its precursor angiotensinogen, leading to a cascade of reactions which elevate blood pressure and increase sodium retention by the kidney in the renin-angiotensin system. Renal Sodium and Water Regulation → angiotensin I → angiotensin II Angiotensin II An octapeptide that is a potent but labile vasoconstrictor. It is produced from angiotensin I after the removal of two amino acids at the c-terminal by angiotensin converting enzyme. The amino acid in position 5 varies in different species. To block vasoconstriction and hypertension effect of angiotensin II, patients are often treated with ace inhibitors or with angiotensin II type 1 receptor blockers. Renal Sodium and Water Regulation → aldosterone Aldosterone A hormone secreted by the adrenal cortex that regulates electrolyte and water balance by increasing the renal retention of sodium and the excretion of potassium. Hyperkalemia:
Renin
Renin
A highly specific (leu-leu) endopeptidase that generates angiotensin I from its precursor angiotensinogen, leading to a cascade of reactions which elevate blood pressure and increase sodium retention by the kidney in the renin-angiotensin system.
Renal Sodium and Water Regulation-angiotensin-
aldosterone
Aldosterone
A hormone secreted by the adrenal cortex that regulates electrolyte and water balance by increasing the renal retention of sodium and the excretion of potassium.
Hyperkalemia system:
A decrease in
mean
Mean
Mean is the sum of all measurements in a data set divided by the number of measurements in that data set.
Measures of Central Tendency and Dispersion arterial pressure (MAP) is sensed by the juxtaglomerular apparatus, which then secretes
renin
Renin
A highly specific (leu-leu) endopeptidase that generates angiotensin I from its precursor angiotensinogen, leading to a cascade of reactions which elevate blood pressure and increase sodium retention by the kidney in the renin-angiotensin system.
Renal Sodium and Water Regulation.
Renin
Renin
A highly specific (leu-leu) endopeptidase that generates angiotensin I from its precursor angiotensinogen, leading to a cascade of reactions which elevate blood pressure and increase sodium retention by the kidney in the renin-angiotensin system.
Renal Sodium and Water Regulation catalyzes the
synthesis
Synthesis
Polymerase Chain Reaction (PCR) of angiotensin I which is converted into
angiotensin II
Angiotensin II
An octapeptide that is a potent but labile vasoconstrictor. It is produced from angiotensin I after the removal of two amino acids at the c-terminal by angiotensin converting enzyme. The amino acid in position 5 varies in different species. To block vasoconstriction and hypertension effect of angiotensin II, patients are often treated with ace inhibitors or with angiotensin II type 1 receptor blockers.
Renal Sodium and Water Regulation by ACE.
Angiotensin II
Angiotensin II
An octapeptide that is a potent but labile vasoconstrictor. It is produced from angiotensin I after the removal of two amino acids at the c-terminal by angiotensin converting enzyme. The amino acid in position 5 varies in different species. To block vasoconstriction and hypertension effect of angiotensin II, patients are often treated with ace inhibitors or with angiotensin II type 1 receptor blockers.
Renal Sodium and Water Regulation induces the
release
Release
Release of a virus from the host cell following virus assembly and maturation. Egress can occur by host cell lysis, exocytosis, or budding through the plasma membrane.
Virology of
aldosterone
Aldosterone
A hormone secreted by the adrenal cortex that regulates electrolyte and water balance by increasing the renal retention of sodium and the excretion of potassium.
Hyperkalemia from the
adrenal cortex
Adrenal Cortex
The outer layer of the adrenal gland. It is derived from mesoderm and comprised of three zones (outer zona glomerulosa, middle zona fasciculata, and inner zona reticularis) with each producing various steroids preferentially, such as aldosterone; hydrocortisone; dehydroepiandrosterone; and androstenedione. Adrenal cortex function is regulated by pituitary adrenocorticotropin.
Adrenal Glands: Anatomy, which travels to the
distal convoluted tubule
Distal convoluted tubule
The portion of renal tubule that begins from the enlarged segment of the ascending limb of the loop of henle. It reenters the kidney cortex and forms the convoluted segments of the distal tubule.
Gitelman Syndrome, where it causes reabsorption of Na+ and water.
CO:
cardiac
Cardiac
Total Anomalous Pulmonary Venous Return (TAPVR) output
These hormones Hormones Hormones are messenger molecules that are synthesized in one part of the body and move through the bloodstream to exert specific regulatory effects on another part of the body. Hormones play critical roles in coordinating cellular activities throughout the body in response to the constant changes in both the internal and external environments. Hormones: Overview and Types act in opposition to the RAAS RAAS A blood pressure regulating system of interacting components that include renin; angiotensinogen; angiotensin converting enzyme; angiotensin i; angiotensin ii; and angiotensinase. Renin, an enzyme produced in the kidney, acts on angiotensinogen, an alpha-2 globulin produced by the liver, forming angiotensin I. Angiotensin-converting enzyme, contained in the lung, acts on angiotensin I in the plasma converting it to angiotensin II, an extremely powerful vasoconstrictor. Angiotensin II causes contraction of the arteriolar and renal vascular smooth muscle, leading to retention of salt and water in the kidney and increased arterial blood pressure. In addition, angiotensin II stimulates the release of aldosterone from the adrenal cortex, which in turn also increases salt and water retention in the kidney. Angiotensin-converting enzyme also breaks down bradykinin, a powerful vasodilator and component of the kallikrein-kinin system. Adrenal Hormones.
Effects of
atrial natriuretic peptide
Atrial natriuretic peptide
A potent natriuretic and vasodilatory peptide or mixture of different-sized low molecular weight peptides derived from a common precursor and secreted mainly by the heart atrium. All these peptides share a sequence of about 20 amino acids.
Renal Sodium and Water Regulation (ANP) on blood volume:
Atrial natriuretic peptide
Atrial natriuretic peptide
A potent natriuretic and vasodilatory peptide or mixture of different-sized low molecular weight peptides derived from a common precursor and secreted mainly by the heart atrium. All these peptides share a sequence of about 20 amino acids.
Renal Sodium and Water Regulation is released by atrial
myocytes
Myocytes
Mature contractile cells, commonly known as myocytes, that form one of three kinds of muscle. The three types of muscle cells are skeletal, cardiac, and smooth. They are derived from embryonic (precursor) muscle cells called myoblasts.
Muscle Tissue: Histology in response to distention and decreases the
release
Release
Release of a virus from the host cell following virus assembly and maturation. Egress can occur by host cell lysis, exocytosis, or budding through the plasma membrane.
Virology of
renin
Renin
A highly specific (leu-leu) endopeptidase that generates angiotensin I from its precursor angiotensinogen, leading to a cascade of reactions which elevate blood pressure and increase sodium retention by the kidney in the renin-angiotensin system.
Renal Sodium and Water Regulation, which results in
sodium
Sodium
A member of the alkali group of metals. It has the atomic symbol na, atomic number 11, and atomic weight 23.
Hyponatremia loss (natriuresis) and water loss (diuresis) in the
urine
Urine
Liquid by-product of excretion produced in the kidneys, temporarily stored in the bladder until discharge through the urethra.
Bowen Disease and Erythroplasia of Queyrat. The loss of volume through the
urine
Urine
Liquid by-product of excretion produced in the kidneys, temporarily stored in the bladder until discharge through the urethra.
Bowen Disease and Erythroplasia of Queyrat decreases
central venous pressure
Central venous pressure
The blood pressure in the central large veins of the body. It is distinguished from peripheral venous pressure which occurs in an extremity.
Central Venous Catheter (
CVP
CVP
The blood pressure in the central large veins of the body. It is distinguished from peripheral venous pressure which occurs in an extremity.
Central Venous Catheter),
preload
Preload
Cardiac Mechanics, and
systemic vascular resistance
Systemic vascular resistance
Afterload is the resistance in the aorta that prevents blood from leaving the heart. Afterload represents the pressure the LV needs to overcome to eject blood into the aorta.
Cardiac Mechanics (SVR), decreasing blood pressure.
GFR
GFR
The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance.
Kidney Function Tests:
glomerular filtration rate
Glomerular filtration rate
The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance.
Kidney Function Tests
NEP: neutral endopeptidase