Term
| What process is happening if substances are moved from the blood to the lumen? |
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Definition
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Term
| What process is happening if substance are moved from the lumen to the blood? |
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Definition
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Term
| Key measures of kidney function (2) |
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Definition
Amount of urine
Concentration of urine |
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Term
| How is the glomerular filtrate modified in the proximal tubule? |
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Definition
-60% of H2O and 60% of NaCl are reabsorbed
-100% of glucose is reabsorbed
-60-85% of bicarbonate is reabsorbed
-small amount of creatinine secreted into tubule
-no change in inulin |
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Term
| How is the glomerular filtrate modified in the loop of Henle? |
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Definition
DESCENDING
-H2O diffuses out passively via vasa recta
-Na+ diffues in to tubule
-osmolality increases
ASCENDING
-Na+ is reabsorbed actively in to blood stream
-not permeable to H2O
-increase in interstitial Na+ concentration causes more H2O to diffuse out of the descending loop
-osmolality in the tubule decreases as Na leaves |
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Term
| How is the glomerular filtrate modified in the distal tubule? |
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Definition
-small amount of Na+ reabsorbed in to bloodstream
-no water movement |
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Term
| How is the glomerular filtrate modified in the collecting duct? |
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Definition
-small amount of Na+ reabsorbed
-aquaporins allow for water movement to further concentrate/dilute urine depending on needs |
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Term
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Definition
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Term
| Why is monitoring GGT (gamma glutamyl transferase) activity useful? |
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Definition
| indicates damage to proximal tubule cells |
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Term
| What are the routes of transport across the proximal tubular epithelium? How do they differ? Which is more common? |
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Definition
Paracellular
-passive diffusion
-1% of SA
Transcellular
-passive or active transport
-99% of SA |
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Term
| Which type of PT transport relies on electrochemical gradients exclusively |
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Definition
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Term
| What is counter transport? |
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Definition
| 2 ions pumped in opposite directions. 1 ion is pumped against the gradient, and a different ion goes with the gradient |
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Term
| What is primary active transport? |
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Definition
| using ATP to transport molecules across a mmb |
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Term
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Definition
| 2 ions pumped in same direction. 1 ion is pumped against the gradient, and a different ion goes with the gradient |
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Term
| How is glucose transported in the proximal tubule? |
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Definition
Secondary active transport (COTRANSPORT) moves glucose across the luminal membrane
Passive transport (CARRIER MEDIATED DIFFUSION) using GLUT1/GLUT2 proteins moves glucose across the basolateral membrane |
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Term
| What is tubular transport maximum? |
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Definition
| The max amount of glucose that can be transported by the tubules |
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Term
| What is the difference between renal origin and non-renal origin glucosuria? |
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Definition
| Renal = problem with tubular transport Non-renal = hyperglycemia causing spillover |
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Term
| Fanconi syndrome is associated with what type of glucosuria? |
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Definition
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Term
| Diabetes mellitus is associated with what type of glucosuria? |
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Definition
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Term
| Where is the majority of glucose absorbed? |
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Definition
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Term
| Where are the majority of amino acids absorbed? |
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Definition
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Term
| Where is the majority of bicarbonate absorbed? |
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Definition
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Term
| Where is the majority of water reabsorbed? |
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Definition
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Term
| What is the main driving force of Na+ reabsorption in the proximal tubule? |
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Definition
| Primary & secondary active transport |
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Term
True or False
The osmolality of glomerular filtrate has no net change as it moves through the proximal tubule |
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Definition
True
because water follows the ions@ |
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Term
True or False
Fluid absorption in the proximal tubule is hypotonic |
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Definition
| false - isotonic ([%] doesn't change overall] |
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