Renal system and homeostasis Flashcards
Principal extracellular ions are…
sodium, potassium, bicarbonate
principal intracellular ions are..
Potassium, magnesium, phosphate
What is Osmolality
-Water and Sodium balance
-Controlled by 2 processes:
1) Osmoregulation = Water control.
2) Volume regulation = Sodium control.
Explain the two different types of disturbances of H2O balance
Dehydration: Excess H2O loss cause Diarrhea or vomiting and Hypovolemia (decrease in plasma volume and loss of blood pressure)
Overhydration:
How is Blood pH regulated
kidneys + resperation
how do kidneys help regulate blood ph
Kidneys help regulate pH by:
-Reabsorbing or producing bicarbonate (a base) to neutralize excess acid.
-Excreting excess bicarbonate when there’s too much base in the blood.
-Excreting acidic metabolic waste products (like hydrogen ions) to lower acidity.
how does Respiratory system help regulate blood ph
Respitory system controls the amount of dissolved carbon dioxide in the blood. This happens quickly through changes in breathing rate—faster breathing removes more carbon dioxide, which can lower acid levels.
What happens in Metabolic acidosis
the body produces too much acid or can’t get rid of it properly. This overwhelms the body’s ability to buffer (neutralize) the acid.
How does the body try to compensate with Metabolic acidosis
The body tries to neutralize excess acid using bicarbonate (a base).
As bicarbonate is used up to neutralize the acid, its levels in the blood fall.
-The body also tries to fix this by hyperventilating (breathing fast) to lower CO2 and reduce acidity.
What happens in Respiratory Acidosis:
happens when the lungs can’t exhale enough CO2 (carbon dioxide), which causes CO2 to build up in the blood..
The excess CO2 reacts with water to form carbonic acid (H2CO3), increasing the acidic level of the blood.
What happens with Respiratory Alkalosis:
- when you hyperventelate you loose alot of CO2 which in return causes loss in carbonic acid leading to excess bicarbonate
List the 3 main functions of the Kidneys
1)Excrete waste products:
Removes end products of metabolism like urea , uric acid, and fatty acids .
2)Controls minerals, electrolytes, acids (pH), and water in the body.
Excretes excess and conserves what’s needed to maintain balance.
Produce hormones:
3) Erythropoietin: Stimulates red blood cell production in the bone marrow.
Renin: Helps regulate blood pressure.
Thrombopoietin: Involved in platelet production.
What are the layers of the Glomerulus
1)Inner layer: Fenestrated capillaries (tiny holes) let some things through.
2)Middle layer: Basement membrane, like a filter that keeps out large molecules.
3)Outer layer: Capillary endothelial cells with special foot processes and filtration slits that further help with filtering.
What are Mesangial cells
These cells help hold the capillaries together, contract to adjust blood flow, and clean up by eating debris.
What is Control of Glomerular Filtration Rate (GFR):
is the rate at which the kidneys filter blood.
What are Key Factors Controlling GFR:
1)Porosity and length of glomerular capillaries: The more pores or openings in the capillaries, the easier it is to filter blood.
2)Fluid and oncotic pressure: The pressure inside the capillaries versus the pressure outside affects how much fluid is filtered.
How does the Kidney Controls GFR
flood flow resistance: The kidneys adjust the afferent arteriole (bringing blood in) to control how much blood flows into the glomerulus. This happens by dilating (widening) or contracting the blood vessels.
2)The macula densa (in the loop of Henle) senses the pressure and helps adjust the blood flow and GFR accordingly.
what is Hyponatremia
Low sodium in the blood, causing cells to swell (water moves into cells).
what is Hypernatremia
High sodium in the blood, causing cells to shrink (water moves out of cells).
What happens when blood becomes too concentrated (high osmolality)
the brain (hypothalamus) senses this and triggers:
Thirst (to drink more water).
Release of antidiuretic hormone (ADH) from the posterior pituitary gland, which makes the kidneys retain water (producing less urine) and helps lower sodium levels.
What happens in Diabetes insipidus:
Caused by lack of ADH secretion or the kidneys’ failure to respond to ADH.
This leads to large amounts of urine production (up to 20 liters per day), causing dehydration.
What does Hypoperfusion mean
low blood flow to the kidneys, often due to low blood pressure or low blood volume
How does the Body Respond to Hypoperfusion
Sensing Low Blood Flow:
Juxtaglomerular cells in the kidneys detect low blood flow and release renin into the bloodstream.
Renin-Angiotensin-Aldosterone System (RAAS):
Renin triggers a series of reactions that help raise blood pressure and increase blood volume to restore kidney perfusion.
What does Renin do in terms of Hypoperfusion
Renin converts angiotensinogen into Angiotensin I then converted into Angiotensin II by an enzyme in the lungs.
Why is Angiotensin imprtant in hypoperfusion
Vasoconstrictor: It causes blood vessels to tighten, raising blood pressure.
Aldosterone release: It stimulates the adrenal glands to release aldosterone, which causes the kidneys to reabsorb more sodium and water, increasing fluid in the bloodstream.
What is special About The RAAS system
its self regulating… Once blood pressure and volume are restored, the system slows down to prevent overcompensation.
What is Renal agenesis
Failure of one or both kidneys to develop
List the different parts of congenital Abnormalities.
1)Renal agenesis
2)Duplications of urinary tract
3)Failure of kidney ascent
4)malposition
What are stages of Renal Failure
Pre-renal:
Hypertension and atherosclerosis of renal artery causing ischemic nephropathy
high sugar levels in blood from diabetes clog and damage tiny vessels in kidney (thickening/scarring)
Post-renal: often obstructive – bladder stones, prostatic diseases, cancer - Damage kidney when urine blockage causes pressure buildup in kidney
Renal: infectious, autoimmune, trauma
What is acute kidney injury
characterized by decreased urine output (50-70%), fluid and electrolyte imbalances
What causes acute renal failure and how is it treated?
Impaired renal blood flow (e.g., low blood pressure, shock)
Tubular damage from infections, toxic drugs, or chemicals
Conditions like atherosclerosis or severe dehydration
WHAT ARE THE TERMS USED TO DESCRIBE LOW URINE/NO URINE
Oliguria (low urine) or anuria (no urine)
What are the stages of Chronic Kidney Disease (CKD) and how is end-stage kidney failure treated?
Stage 1: Normal kidney function
Stage 2: Mild kidney damage
Stage 3: Moderate decline in kidney function
Stage 4: Severe decline in kidney function
Stage 5: End-stage renal disease (ESRD) – complete kidney failure
WHAT IS Nephrotic Syndrome
kidney problem where the glomerulus (the filtering part of the kidney) is damaged. This damage causes lots of protein to leak into the urine (called nephrosis), which lowers protein levels in the blood.
WHAT ARE IMPORTANT CLINICAL INDICATIONS OF Renal Disease - Nephrotic Syndrome
ALL TYPES OF EDEMA
WHAT CONDITION IS MINIMAL IN CHILDREN WITH THE HELP PF CORTICOSCOIDS BUT PROGRESSIVE IN ADULTS
Renal Disease - Nephrotic Syndrome
what happens with Hypertensive Nephrosclerosis
Result of severe, uncontrolled hypertension (high blood pressure).
What is Diabetic Nephropathy
Complication of long-term diabetes (high blood sugar), often with hypertension (high blood pressure).
What happens during Diabetic Nephropathy?
High blood sugar causes thickening of the glomerular basement membrane. leading to glomerulosclerosis (scarring).
This damage can also cause nephrosclerosis (scarring of blood vessels in the kidney).
Progression: Once the damage starts, it can’t be fully reversed, but controlling blood sugar and blood pressure can slow the damage.
What happens durring end stage renal disease?
Uremia:Buildup of waste products like urea in the blood (due to protein metabolism).
Fluid, electrolyte, acid–base regulation failure
Metabolic acidosis
Lack of erythropoietin leads to anemia
What is Glomerulonephritis
Inflammation of the glomeruli caused by immune reaction within glomerulus - Autoimmunity
What happens in Glomerulonephritis
The immune complexes clog the glomeruli, causing inflammation and damage.
Leukocytes (white blood cells) move in, releasing enzymes that cause further damage and necrosis (death) of the glomeruli.
This reduces the kidneys’ ability to filter, leading to low urine output and waste buildup in the blood.
What type of renal cysts you don’t have to worry about if they grow
Solitary cysts
Multiple cysts can lead to?
polycystic kidney disease (PKD)
What causes polycystic kidney disease (PKD)
Congenital: PKD is usually genetic (inherited), often as autosomal dominant (passed down from one parent).
PKD1/2 genes: The most common cause of multiple cysts.
What causes Diseases of Urinary Tract (UTI)
Most infections are caused by gram-negative intestinal bacteria that contaminate perianal and genital areas and ascend urethra
What are some protective features against UTI
Conditions protective against infection
Free urine flow
Large urine volume
Complete bladder emptying
Acid urine: Most bacteria grow poorly in an acidic environment
What is Cystitis
Bladder infection
More common in women than men; urethra in female is shorter. also common in older men.
intercourse promotes transfer of bacteria from urethra to bladder
What is Pyelonephritis
Involvement of upper urinary tract
Ascending infection from the bladder (ascending pyelonephritis)
Carried to the kidneys from the bloodstream (hematogenous pyelonephritis)
What are small kidneys stones called
Renal colic
