Renal Function Flashcards by Liz Haywood

List the 4 components of the urinary system

Kidney
Ureter
Bladder
Urethra

How well did you know this?

Not at all

Perfectly

Anatomy of the kidney

- Vascular supply

Efferent arteriole → outgoing blood
Afferent arteriole → incoming blood
Peritubular capillaries
Vasa recta

How well did you know this?

Not at all

Perfectly

Anatomy of the kidney

- Location of the medulla

Loops of Henle

- Collecting ducts

How well did you know this?

Not at all

Perfectly

Anatomy of the kidney

- Location of cortex

Where glomeruli are on outside edge

How well did you know this?

Not at all

Perfectly

Anatomy of the kidney

- Location of the calices

Where the collecting ducts dump

How well did you know this?

Not at all

Perfectly

Anatomy of the kidney

- Location of the renal pelvis

Trunk that will empty into the ureter

How well did you know this?

Not at all

Perfectly

Microscopic anatomy of the nephron in anatomical order starting w/ the glomerulus and ending w/ collecting ducts

Afferent arteriole → efferent arteriole → blood filtered in glomerulus → proximal convoluted tubules → loops of Henle → distal convoluted tubules → collecting ducts

How well did you know this?

Not at all

Perfectly

List the 3 functions of the kidney

Excretion
Homeostatic regulation
Endocrine

How well did you know this?

Not at all

Perfectly

List 2 plasma constituents that are not normally filtered through the glomerulus

High molecular weight plasma proteins

- Cells

How well did you know this?

Not at all

Perfectly

Rate in mL/minute that substances are filtered through the kidney’s glomeruli

GFR

How well did you know this?

Not at all

Perfectly

Normal GFR in mL/minute

125-130 mL/min

How well did you know this?

Not at all

Perfectly

Two clinical uses for the measurement of GFR

Measure of number of functioning nephrons

- Sensitive and specific marker of changes in overall renal function

How well did you know this?

Not at all

Perfectly

Three forces which determine normal glomerular filtration pressure

Hydrostatic of blood
Fluid pressure (glomerular hydrostatic pressure)
Plasma oncotic pressure (colloid)

How well did you know this?

Not at all

Perfectly

Net movement of substance against a concentration or electrical gradient requires energy expenditure

Mechanism of active tuberular absorption

How well did you know this?

Not at all

Perfectly

Substance moves by simple diffusion as a result of a concentration or electrical gradient; no energy expenditure

Mechanism of passive tuberular absorption

How well did you know this?

Not at all

Perfectly

List 10 substances reabsorbed in teh PCT

Na+
HCO3-
Glucose
Amino acids
Proteins
Phosphate
Sulfate
Mg2+
Ca2+
Uric acid

How well did you know this?

Not at all

Perfectly

What is the specific renal threshold for glucose?

About 160 mg/dL

How well did you know this?

Not at all

Perfectly

Countercurrent mechanism

- Major purpose

Purpose is to remove water from the filtrate on the way down the descending loop making it very salty at the bottom of the loop. Then, on the way up the ascending loop, active reabsorption of sodium and chloride ions occurs. OR like a water heater, allows for the reabsorption of H2O, Na, Cl, and urea with less energy expenditure

How well did you know this?

Not at all

Perfectly

Countercurrent mechanism

- Location in the nephron

Loops of Henle

How well did you know this?

Not at all

Perfectly

Countercurrent mechanism

- Differentiation in the histology of the descending and ascending limbs

Descending: permeable to water so there is passive water and urea reabsorption
Ascending: impermeable to water so there is active reabsorption of sodium and chloride

How well did you know this?

Not at all

Perfectly

Countercurrent mechanism

- Movement of Na, Cl, urea, and H2O in or out of the renal tubules

Sodium: out
Chloride: out
Urea: in
Water: out

How well did you know this?

Not at all

Perfectly

List 3 distinct regulatory functions of the DCT

Responisble for acid-base, water, and electrolyte balance control in the nephron so…

Sodium reabsorption
Potassium secretion

How well did you know this?

Not at all

Perfectly

List 4 substances that are normally reabsorbed in the DCT?

Reabsorption of sodium, chloride, bicarbonate, and water

How well did you know this?

Not at all

Perfectly

List 4 substances that are normaly secreted in the DCT

Secretion of potassium, hydrogen ions, ammonium, and uric acid

How well did you know this?

Not at all

Perfectly

Specific hormone that exerts its effect on the DCT

Aldosterone

What substances are normally reabsorbed in the collecting ducts?

↑ or ↓ water adsorption is controlled here

What hormone exerts its effect on the collecting duct?

Antidiuretic hormone (ADH/vasopressin) - Presence causes water reabsorption by widening pores - Absence causes ↓ water readsorption

``` Juxtaglomerular apparatus (JGA) - Function ```

Regulated the function of each nephron

``` Juxtaglomerular apparatus (JGA) - Location ```

Found b/w the vascular pole of the glomerulus and the returning DCT of the same nephron

``` Juxtaglomerular apparatus (JGA) - Specific functions of granular cells ```

Secrete renin, which is an enzyme that is the starting point for the renin-angiotensin-aldosterone system (RAAS)

``` Juxtaglomerular apparatus (JGA) - Specific functions of macula densa cells ```

Regulate [Na] and [Cl] by sensing (NaCl) in the DCT

``` Juxtaglomerular apparatus (JGA) - Specific functions of mesangial cells ```

Receive stimulation from sympathetic nervous system to modulate actions of the JGA

``` Juxtaglomerular apparatus (JGA) - Importance of its location ```

Location is critical to its function in regulating renal blood flow and the glomerular filtration rate

3 basic procedures involved in renal excretion

- Filtration - Reabsorption - Secretion

In FILTRATION, are substances being conserved in the blood or are they excreted in the urine?

Going into forming urine from blood

In REABSORPTION, are substances being conserved in the blood or are they excreted in the urine?

Capillary system taking substance into the blood

In SECRETION, are substances being conserved in the blood or are they excreted in the urine?

From blood to the secretion

Hypothalamic and ADH regulation of water balance | - 3 stimuli for the water output area of the hypothalamus

- ↑ in extracellular water osmolarity - ↑ in angiotensin II - ↓ in baroreceptor and distension receptor activity

Hypothalamic and ADH regulation of water balance | - Primary stimulus for ADH release

High blood pressure osmolarity

Hypothalamic and ADH regulation of water balance | - Effect that ADH causes on the collecting ducts of the kidney

↑ pore size → absorb more water

Sodium regulation | - Renal handling of sodium in every major portion of the nephron

Sodium is exchanged w/ H+ all along the nephron

Sodium regulation | - Effect of the renin-angiotensin-aldosterone system

↑ Na+ reabsorption

Sodium regulation | - Where aldosterone exerts its effect in the nephron

Control regulation in DCT

Renin-angiotensin-aldosterone system | - Specific site in the nephron where renin is produced

Juxtaglomerular apparatus

Renin-angiotensin-aldosterone system | - 3 specific stimuli for renin release

- ↓ renal perfusion pressure - Sympathetic nerve stimulation - ↓ [Na] in DCT

Renin-angiotensin-aldosterone system | - Biochemical conversions from angiotensinogen to angiotensin II

- Renin converts angiotensinogen to angiotensin I in the liver - Angiotensin converting enzyme (ACE) converts angiotensin I to angiotensin II in the lungs

Renin-angiotensin-aldosterone system | - Organs in which the conversion of angiotensinogen to angiotensin II occurs

Liver to the lung

Renin-angiotensin-aldosterone system | - 4 physiological effects of angiotensin II

- Most powerful vasoconstrictor - Affects water intake of hypothalamus - Affects water output and causes the release of ADH from hypothalamus - Causes aldosterone release from adrenal cortex

Renin-angiotensin-aldosterone system | - Effect of aldosterone on serum sodium and potassium levels

DCT retains more sodium and secretes potassium (therefore ↓ potassium)

Effect of BNP on sodium levels in the blood

BNP causes Na+ excretion

The condition that may be assessed via BNP measurements

CHF

The two substances that the kidney regulates to maintain acid-base balance and whether these substances are normally reabsorbed or secreted

- Reabsorption of bicarbonate | - Secretion of hydrogen ions

4 renal mechanisms by which the kidney maintains acid-base balance and the site in the nephron where these occur

- React w/ filtered bicarbonate ions - React w/ filtered buffers to form titrateable acids - Reacts w/ secreted ammonia to form ammonium ions - Exchange w/ Na+

Renal regulation of H+ and [HCO3-] according to | - Mechanism for the reaction of H+ w/ filtered HCO3-

Renal regulation of H+ and [HCO3-] according to | - Mechanism for the reaction of H+ w/ phosphate buffers

Renal regulation of H+ and [HCO3-] according to | - Mechanism for the reaction of H+ w/ secreted ammonia

Renal regulation of H+ and [HCO3-] according to | - Mechanism for free H+ excretion

List the 3 important hormonal functions of the kidney

- Vitamin D metabolism - EPO production and release - Renin production in JGA that results in hormone release

Microscopic structure which regulates the function of each nephron; named for its proximity to the glomerulus

JGA

An enzyme that is the starting point for the RAAS

Renin

Responsible for filtration of the blood; it's selective permeability does not allow large molecular weight compounds to be filtered

Glomerulus