Basic and Clinical Pharmacology 12th ed
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| 1214686131 | What substances are reabsorbed in descending loop of Henle? | WATER. PASSIVE re-absorption. | 0 | |
| 1214686132 | Which diuretic agents are active in the descending LoH? | NO AGENTS are currently in use. | 1 | |
| 1214696122 | TRUE or FALSE. Glomerulus has poor water permeability. | FALSE. Glomerulus has VERY HIGH water permeability. | 2 | |
| 1214696123 | Name diuretics with major action on glomerulus. | No diuretics act on glomerulus. | 3 | |
| 1214739967 | Which substances are reabsorbed in the straight segment of PT? | Organic ACID and BASES. Diuretics. | 4 | |
| 1214739968 | Which parts of nephron have high permeability for water? | Glomerulus PCT PTSS ThDLoH | 5 | |
| 1214739969 | Which parts of the nephron have low permeability to water? | TAL DCT | 6 | |
| 1214847157 | Which part of the nephron Inulin is reabsorbed? | Inulin is NOT REABSORBED in the tubules. | 7 | |
| 1216269244 | Nearly 100% of glucose and amino acids are reabsorbed where? | In PCT. | 8 | |
| 1214739971 | Which part of nephron is responsible for re-absorption of most of bicarbonate? | PCT Some 85% of bicarbonate is reabsorbed here. | 9 | |
| 1214739972 | Where majority of Na+, K+, Ca++ and Mg++ is reabsorbed? | PCT is the part where some 65% of these ions are reabsorbed. | 10 | |
| 1214739973 | Which part of the nephron is carbonic anhydrase is effective in? | PCT. | 11 | |
| 1214847158 | Complete the sentence. ... is a substance that is ... but not reabsorbed or secreted in tubules. | INULIN is a substance that is FILTERED but not reabsorbed or secreted in tubules. | 12 | |
| 1214739974 | What are the functions of CA in PCT? | Reabsorption of bicarbonate. | 13 | |
| 1214739975 | What are the consequences of CA being inactive in PCT? | Increased EXCRETION of BICARBONATE. | 14 | |
| 1214739976 | What transporters are active in PCT? | - NHE3 - Na+/H+ Exchanger; - CA - Carbonic Anhydrase. | 15 | |
| 1214739977 | What structure is responsible for transport/reabsorption of water in the Descending Loop pf Henle? | Aquaporins. | 16 | |
| 1214847159 | Which substance is reabsorbed via paracellular pathway in PCT? | POTASSIUM. | 17 | |
| 1215117195 | How the mechanism of NaHCO3 reabsorption is initiated? | The reabsorption starts with NHE3 pump which pumps Na+ from the tubular lumen into the cell in exchange for H+. From within the cell NKATP pump removes intracellular Na+ in order to maintain low intracellular [Na+]. | 18 | |
| 1214847161 | How is water reabsorbed in PCT? | Water is reabsorbed PASSIVELY in PCT. | 19 | |
| 1214847162 | What is importance of inulin? | Inulin a substance that is NOT REABSORBED or SECRETED in the tubules, that is useful to use as an indicator against which concentration of other substances can be measured. | 20 | |
| 1214847163 | Complete the sentence. Inulin is a substance that is ... in tubules. | Inulin is a substance that is FILTERED in tubules. | 21 | |
| 1214847164 | Which part of nephron is inulin secreted in the kidney? | Inulin is NOT SECRETED in any part of nephron. It is FILTERED in GLOMERULUS. | 22 | |
| 1214847165 | What part of filtered glucose is reabsorbed in the PCT? | Virtually ALL of filtered GLUCOSE is reabsorbed in PCT. | 23 | |
| 1215238702 | What is the mechanism behind reabsorption of NaCl in DCT? | Na+/Cl- CO-TRANSPORTER (NCC) is responsible for reabsorption. |  | 24 |
| 1215218235 | TRUE or FALSE. 25% of NaCl is reabsorbed in TAL. | TRUE. | 25 | |
| 1214847166 | NHE initiates what process in PCT? | NHE initiates REABSORPTION of SODIUM BICARBONATE in PCT by reabsorbing Na+. | 26 | |
| 1214847167 | Which enzyme is responsible for reabsorption of NaHCO3 in the kidney? | Carbonic Anhydrase. |  | 27 |
| 1214879121 | What is the mechanism of CA action? | NaHCO3 → dissociation → Na+ + HCO3-. Na+ → exchange → H+ via NHE3 => increase in intraluminal H+. H+ + HCO3- = H2CO3. H2CO3 → dehydration by CA → H2O + CO2. CO2 diffuses into tubular cells. CO2 + H2O → rehydration by CA → to H2CO3. H2CO3 dissociates into H+ + H2CO3-. 2CO3- then transported by BASOLATERAL MEMBRANE TRANSPORTER into interstitium. | 28 | |
| 1215186455 | How is NaCl reabsorbed in the PCT? | The reabsorption of NaCl is the result of movement of Na+ across apical membrane in EXCHANGE to H+ via NHE3 TRANSPORTER. The movement of H+ into the lumen increases luminal [H+]. This in response ACTIVATES Cl-/BASE EXCHANGER, which moves Cl- from the lumen into the cells, thus balancing increased acidity in the PCT. The net result is reabsorption of NaCl. | 29 | |
| 1215218236 | Which part of the nephron are NSAIDs, Uric Acid and diuretics are secreted into the lumen? | NSAIDs, Uric Acid and diuretics are secreted into the lumen in PCT. | 30 | |
| 1215218237 | TRUE or FALSE. In Descending Loop of Henle interstitium is hypotonic. | FALSE. The interstitium surrounding the LH is HYPERTONIC - this results in the OSMOTICALLY driven REABSORPTION of H2O. | 31 | |
| 1215218238 | TRUE or FALSE. Like in DLH, water is osmotically well absorbed in TAL. | FALSE. TAL is RELATIVELY water IMPERMEABLE. | 32 | |
| 1215218239 | TRUE or FALSE. Overall about 40% of NaCl is reabsorbed in TAL. | FALSE. 25% of NaCl is reabsorbed in TAL. | 33 | |
| 1215218240 | Why TAL is called diluting segment? | As NaCl is ACTIVELY REABSORBED from TAL - this DECREASES osmolality of the luminal content as TAL is practically IMPERMEABLE to WATER. | 34 | |
| 1215218241 | How does NK2CL co-transporter work? | NK2CL co-transporter transports Na+, K+ and 2Cl- from the lumen into the cell. The transport of K+ creates excess of K+ within the cell. This results in BACKLEAK of K+ OUT of the cell back into the lumen. This BACKLEAK creates driving FORCE for reabsorption of CATIONS Mg++ and Ca++ via PARACELLULAR pathway. |  | 35 |
| 1215221786 | Complete the sentence. As a result of action of loop diuretics there is ... of lumen-positive potential. | As a result of action of loop diuretics there is DECREASE of lumen-positive potential. | 36 | |
| 1215221787 | How is lumen positive potential affected by action of loop diuretics? | Loop diuretics block NK2CL co-transporter, which results in decrease in NaCl reabsorption and this causes REDUCES lumen-positive potential. | 37 | |
| 1215221788 | Why there is decreased lumen-positive potential with loop diuretics? | Loop diuretics block NK2CL transporter. This PREVENTS BACKLEAK of K+ from the cell into the lumen and this in turn causes DECREASE in lumen-positive potential. (and in turn prevents reabsorption of Mg++ and Ca++ via PARACELLULAR pathway). | | 38 |
| 1215224885 | How urine is further diluted in DCT? | Approximately 10% of NaCl is reabsorbed in DCT at the same time DCT is almost IMPERMEABLE to WATER. This leads to further dilution of urine. | 39 | |
| 1215238703 | TRUE or FALSE. Due to backleak of K+ out of he cell into the lumen Ca++is electrically driven out of lumen. | FALSE. There is NO BACKLEAK of K+ into the lumen and so there is NO ELECTRICALLY driven REABSORPTION Ca++. | 40 | |
| 1215238704 | How is Ca++ reabsorbed in the DCT? | Ca++ is reabsorbed from the lumen via PTH driven Ca++ channel and from the cell, via BASO-LATERAL Na+/Ca++ EXCHANGER back into interstitium. | | 41 |
| 1215238705 | Which group of diuretics is active in DCT? | THIAZIDE diuretics. | 42 | |
| 1215238706 | What is the collecting tubule system? | The collecting tubule system connects DCT to the ureter. It consists from: - CONECTING TUBULE; - COLLECTING TUBULE; - COLLECTING DUCT. | 43 | |
| 1215238707 | Which part of nephron is responsible for the final concentration of Na+ in the urine? | The COLLECTING TUBULE SYSTEM. | 44 | |
| 1215238708 | What are the three important roles that the Collecting Tubule System plays in the formation of urine? | 1. Final concentration of Na+ in the urine 2. CTS is the site where mineralocorticoids play the important role in urine formation; 3. CTS is the most important site for K+ secretion by the kidney. | 45 | |
| 1215239362 | What are the main two types of cells in the CTS? | - Principal cells - Intercalated cells (α and β) | 46 | |
| 1215241638 | What are intercalated cells responsible for? | There are TWO types of INTERCALATED cells - α and β. The α-cells are responsible for SECRETION of H+. The β-cells are responsible for SECRETION of BICARBONATE. | 47 | |
| 1215241639 | What is the role of principal cells in the CTS? | Principal cells are responsible for transport of of Na+, K+ and WATER. | 48 | |
| 1215243195 | What are the transporter responsible for movement of Na+ and K+ across the cell membrane in principal cells? | There are NO TRANSPORTERS for Na+ and K+ in principal cells. Na+ abd K+ move across cellular membrane through dedicated Na+ and K+ channels. |  | 49 |
| 1215245885 | How to explain lumen negative potential in CTS? | Due to the fact that Na+ and K+ movement across the membrane in principal cells DOES NOT involve ANIONS, and there is EXCESS of Na+ movement into the cell compared to K+ moving out of the cell, - there is excess MOVEMENT of the positive CHARGE across the membrane, creating luminal negative charge of 10-50mV. | 50 | |
| 1215251286 | How Cl- is transported from the lumen in CTS? | As there is negative (10-50mV) luminal potential in CTS, this creates driving electrical force for reabsorption of Cl- via PARACELLULAR pathway back into blood. This, in turn, drives K+ from the cell into the lumen via the K+ channel into the lumen. | 51 | |
| 1215251287 | What is the important relationship between Na+ and K+ in the CTS? | The more Na+ is delivered to CTS, the more K+ is excreted. Likewise if there is increased delivery of an anion that can not be reabsorbed as easy as Cl- (e.g. HCO3-), the negative luminal potential is further increased and causes furthermore increase in K+ excretion. | 52 | |
| 1215251288 | What regulates the function of Na Epithelial channel (ENaC) in CTS? | ALDOSTERON regulates activity (activates) of ENaC, leading to increased reabsorptio of Na+ in CTS. Aldosterone also stimulates Na+/K+A pump in basolateral membrane, The activation of NKA leads to further increase in transmembrane potential difference enhancing Na+ reabsorption and K+ secretion. | 53 | |
| 1216839089 | What are the other names for Vasopressin? | - ADH - Arginine Vasopressin (AVP) | 54 | |
| 1216839090 | How many types of Vasopressin receptors are known? | There are two types of receptors: - V1 - in vascular beds and CNS - V2 - in kidneys | 55 | |
| 1216839091 | How V2 receptors function? | V2 receptors are located on basolateral membrane part of the cell. The secretion of ADH stimulates the receptors (GPCR) and leads to insertion of AQUAORINS in the apical membrane of the cells which dramatically ENCHANCE water REABSORPTION. |  | 56 |
| 1216839092 | What is the other important action of ADH in reabsorption of water in the CDS? | ADH stimulated Urea Transporter molecules (UT1) in the apical membrane of part of CDS. | 57 | |
| 1217117316 | When is effect of Acetazolamide is notable? | It starts acting within 30 minutes with peak effect at 12 hours. | 58 | |
| 1217501720 | What type of acidosis develops in Acetazolamide use? | HYPERCHLORAEMIC metabolic acidosis. | 59 | |
| 1217501723 | What is the mechanism of hyperchloraemic metabolic acidosis development in Acetazolamide use? | Increased NaCl reabsorption. | 60 | |
| 1217501725 | What are the important uses of CA inhibitors? | - Decrease in production of aqueous humor leading to decrease in intraocular pressure in glaucoma; - Decrease in CSF production by choroid plexus - may relieve increased ICP. | 61 | |
| 1217501727 | What are adverse effects of Acetazolamide? | - Hypokalaemia; - Renal stones; - Hyeprchlraemic metabolic acidosis. | 62 | |
| 1217501730 | What is the interaction between Acetazolamide and Phenytoin? | There is decreased decreased excretion of Phenytoin leading to toxic levels of Phenytoin. | 63 |
