Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key


Play button


Play button




Click to flip

31 Cards in this Set

  • Front
  • Back
Water excretion =
pressure diuresis

The effect of pressure to increase water excretion is called pressure diuresis.
Salt excretion =

The effect of pressure to increase Na excretion is called pressure natriuresis
Renal System for Arterial Pressure Control
Art pressure elevated by transfusing in 400 ml blood
Plays a dominant role in long term pressure control.
As extracellular fluid volume increases arterial pressure increases.
The increase in arterial pressure causes the kidneys to lose Na and water which returns extracellular fluid volume to normal.
The major determinants of long-term arterial pressure control.
Based on renal function curve
Salt and water intake line
Long term arterial pressure determined by:
Degree of the pressure shift for water and salt output
Level of water and salt intake
vit B deficiency, vaso dilation
elevated osteoclastic activity
Paget’s –
Failure of Total Peripheral Resistance to Elevate Long-term Arterial Pressure
Cardiac output and art. Pressure vary greatly from normal, and long term resistance increases, but renal salt and water excretion remains constant

And overall art pressure is ‘normal’

Changes in TPR does not affect long-term arterial pressure level.
One must alter the renal function curve in order to have long-term changes in arterial pressure.
Changing renal vascular resistance does lead to long-term changes in arterial pressure .
_______ is a Major Determinant of ECFV

(much more than H2O intake)
As Na intake is increased; Na stimulates drinking, increased Na concentration stimulates thirst and ADH secretion.
Changes in Na intake leads to changes in _________ fluid volume
extracellular (ECFV).
ECFV is determined by the balance of
Na intake and output
Higher salt in tissues (and hypothalamus) causes thirst stimulus.
To reset tissue osmolarity to normal, water is retained to dilute salt conc.
Tissue saltiness in posterior pituitary causes release of ADH, saves water in kidneys & concentrates urine salt
Resultant increases in ECF volume increases blood pressure more so, and for a longer period than, increases in blood volume.
Chronic Hypertension
Mean art pressure stays above normal.
Results in:
Excess cardiac workload
Vascular damage and cerebral ‘events’
Kidney damage
Renin-Angiotensin System
Renin is synthesized and stored in modified smooth muscle (JG) cells in afferent arterioles of the kidney.
Renin is released in response to a fall in art. pressure.
Renin acts on a substance called angiotensinogen to form a peptide called angiotensin I. (10 a.a.s)
A-I is converted to A-II (8a.a.s) by a converting enzyme located in the endothelial cells in the pulmonary circulation. Powerful vasoconstrictor
______ is released in response to a fall in art. pressure.
Renin Angiotensin System
Causes vasoconstriction
Causes Na retention by direct and indirect acts on the kidney- so water is also retained.
It works directly on the kidneys to save water and salt (constrict renal art flow & increases renal tubular resorption of salt & water)
It cause aldosterone release from the adrenals that affect distal kidney tubules to save water and salt
Causes shift in renal function curve to right
Important response to sudden blood loss
Renin Angiotensin System Effect of Na Intake
RAS is important in maintaining a normal Art. Press. during changes in Na intake.
As Na intake is increased renin levels fall to near 0.
As Na intake is decreased renin levels increase significantly.
Eating pizza is O.K..
Primary (essential) Hypertension
Weight gain, non-active lifestyle
C.O. is increased
sympathetic activity is increased
Angiotensin II and aldosterone are increased (d.t. increased symp. effect on kidneys)
Impaired renal natriuresis
Treat with life style changes, vasodilators and natriuretic and diuretic drugs, ACE inhibitors
_________ lower arteriolar resistance and increase venous capacitance; increase cardiac output and cardiac index, stroke work and volume, lower renovascular resistance, and lead to increased natriuresis (excretion of sodium in the urine).
ACE inhibitors
ACE inhibitors
ACE inhibitors lower arteriolar resistance and increase venous capacitance; increase cardiac output and cardiac index, stroke work and volume, lower renovascular resistance, and lead to increased natriuresis (excretion of sodium in the urine).
Normally, angiotensin II will have the following effects: - vasoconstriction (narrowing of blood vessels) - cardiac hypertrophy - stimulate the adrenal cortex to release aldosterone, a hormone which acts on kidney tubules to retain sodium and chloride ions and excrete potassium. Sodium is a "water-holding" molecule, so water is also retained. This leads to increased blood volume, hence an increase in blood pressure. - stimulate the posterior pituitary into releasing vasopressin (ADH) which also acts on the kidneys to increase water retention.
With ACE inhibitor use, the effects of angiotensin II are prevented, leading to decreased blood pressure.
Epidemiological and clinical studies have shown that ACE inhibitors reduce the progress of _________ independently from their blood pressure-lowering effect.
diabetic nephropathy

This action of ACE inhibitors is utilized in the prevention of diabetic renal failure.
Hypertension involving Angiotensin II
From tumors of the JG cells – secreting high levels of renin and forming high levels of Angiotensin II.
Which causes vasoconstriction and salt & water retention

From Kidneys responding to restricted flow into them from the renal artery – Goldblatt one and two kidney preps – put out more renin.
Angiotensin – dependant hypertension
From diseased kidneys that secrete renin chronically (renal hypertension)
Ischemic sections in damaged kidneys constrict blood flow, or limit blood flow, into normal areas of the kidney that read ‘impaired flow” and produce more renin that begins the hypertensive cascade. Common in older patients with kidney damage
Hypertension from volume load & vasoconstriction
Coarctation of the aorta – malformed aorta. Lower aorta divides into multiple vessels and resistance is higher and flow is lower to the kidneys. They produce renin….pressure rises in the upper body until the kidneys reach normal pressures.
Extremities have normal pressures, because they are locally controlled.
Other hypertensions
Toxemia of pregnancy-preeclampsia
Caused by ischemia of the placenta which releases toxic cellular products and raises maternal pressures
Damage to the carotid bodies or Solitary Nucleus
Factors Which Decrease Renal Excretory Function and Increase Blood Pressure
Angiotensin II
Sympathetic nervous activity
In a healthy individual, a delicate balance between vasoconstriction and vasodilation is maintained by endothelin, calcitonin and other vasoconstrictors on the one hand and nitric oxide, prostacyclin and other vasodilators on the other
Factors Which Increase Renal Excretory Function and Reduce Blood Pressure
Atrial natriuretic peptide
Nitric oxide
Different Forms of Hypertension
Primary or Essential hypertension
Renovascular Hypertension
Neurogenic-Sleep Apnea – along with obesity
Chronic Renal Disease
Pheochromocytoma (adrenal medulla tumor) – elevated epinephrine levels
Pregnancy-induced Hypertension (preeclampsia)
Exogenous substances
(alcohol, steroids, sympathomimetics)
Drugs which affect renal blood flow to tx HTN:
Inhibition of sympathetic nervous system
Angiotensin Converting Enzyme inhibitors – ACE inhibitors
Drugs that inhibit Na reabsorption to tx HTN:
- Diuretics & natriuretics