Urinary System 2 Flashcards
How does Dehydration/ Sweat Loss alter GFR? (10)
How does the body regulate when it detects a change in blood pressure?
Stimulus: venous, atrial, and arterial blood pressure changes monitored by baroreceptors in each location.
Response: alter renal sympathetic firing to kidney.
Additional arterial response – altered arterial pressure can also change GFR without involving altering renal sympathetic firing.
What are the 2 main GFR-altering hormones?
Angiotensin II
Atrial natriuretic peptide (ANP)
What is Angiotensin II?
How does it affect GFR?
Released inactive (angiotensinogen) from liver ultimately converted to angiotensin II.
Response:
circulates in the blood to kidneys and vasoconstricts afferent and efferent arterioles; more receptors on afferent arteriole
Decrease GFR
What is Atrial natriuretic peptide (ANP)?
How does it affect GFR?
Released from heart.
Response: circulates in blood to kidneys and vasodilates afferent arterioles and vasoconstricts efferent arterioles / also increases SA of glomerulus by relaxing mesangial cells –
Both Responses Increase GFR.
In regards to Glomerular Filtration, How much do we keep? How much do we eliminate?
How much to keep:
During glomerular filtration, almost all substances in the blood are filtered into the glomerular space and leave in renal tubules
How much to eliminate:
Waste products, toxins, and excess substances (e.g., urea, creatinine, certain ions) are primarily eliminated through glomerular filtration into the renal tubule. These substances are meant to be eventually excreted from the body as
In regards to Tubular Secretion, How much do we keep? How much do we eliminate?
How much to keep:
Tubular secretion involves actively transporting certain substances from the peritubular capillaries into the renal tubule
How much to eliminate:
The substances being secreted are meant to be eliminated from the body, as they are often waste products or need to be removed for various physiological reasons
In regards to Tubular Reabsorption, How much do we keep? How much do we eliminate?
How much to keep:
Tubular reabsorption involves the reabsorption of water and various solutes from the renal tubule back into the peritubular capillaries
How much to eliminate:
Tubular reabsorption aims to retain essential substances,
What is the Tubular lumen?
inner cavity of renal tubule.
What cells make up the Renule Tubule wall?
Epithelial cell –
cells making up the renal tubule wall.
Where are Epithelial Cells?
cells making up the renal tubule wall.
What is the fluid surrounding the renal tubule? What are the blood vessels in the area called?
Interstitial fluid
- extracellular fluid surrounding renal tubule.
Blood vessel
- peritubular capillaries
What are the 2 Tubular epithelial cell membranes?
Apical Membrane
- between tubule lumen and inside tubular epithelial cell.
Basolateral Membrane
- between inside tubular epithelial cell and interstitial fluid.
Image
What is a Semipermeable membrane?
(selectively permeable)
Semipermeable membrane
- lets some things pass and not others.