Advanced Renal Physiology and Pathophysiology Quiz

Stenosis will result in hypoperfusion of the affected kidney, leading to increased renin levels. However, the unaffected kidney will not experience reduced blood flow and will maintain normal renin levels. Aldosterone, induced by Angiotensin II, acts on both kidneys to retain sodium and water, contributing to hypertension.

Rhabdomyolysis is the breakdown of muscle tissue that leads to the release of myoglobin, causing kidney damage. This can occur after strenuous physical activity such as a long race. Dehydration due to sweating excessively may not lead to glucose in urine. Type 1 diabetes with ketoacidosis presents with high blood sugar levels, ketones in urine, but not specifically with glucose in urine. Exercise-induced acute kidney injury is a possibility but does not explain the presence of glucose in urine.

The correct calculations for total body water, intracellular fluid volume, extracellular fluid volume, plasma volume, interstitial fluid volume, and hematocrit were provided in the answer. The incorrect answers do not align with the correct calculations provided.

To calculate the plasma volume, we need to divide the amount of radiolabeled albumin injected (1000 mg) by the concentration of albumin in plasma (25 mg/dL). This gives us 40 dL, which is equal to 4 Liters.

Amino acids, Glucose, and Electrolytes are indeed freely filtered in the glomerulus, along with other substances. Their reabsorption is essential for the body's functioning, while waste products like creatinine are not reabsorbed.

In the correct answer, it is explained that all 3 layers of the Glomerulus play a role in preventing the filtration of Albumin by creating a charge barrier due to the presence of negatively charged glycoproteins. This charge barrier repels negatively charged molecules like Albumin. The incorrect answers provide alternative scenarios that do not accurately describe the components involved in preventing the filtration of Albumin.

When the urine flow rate is higher, the clearance of the substance increases, leading to more substance being excreted in urine. This results in higher urine concentration and lower plasma concentration. Higher urine concentration with higher urine flow rate means more substance is being removed from plasma. As a result, the volume of plasma from which the substance is cleared per unit time increases.

The correct answer explains how GFR is indirectly determined using inulin clearance and how this information can be used to differentiate net secretion/reabsorption of substances in the kidney.

Increased oncotic pressure in Bowman's space and an increase in hydrostatic pressure of glomerular capillaries together increase the net filtration pressure, causing an increase in the glomerular filtration rate (GFR). This is due to the forces favoring filtration being greater than the opposing forces, leading to more fluid being filtered into Bowman's space.

To calculate GFR, you first multiply the Urine Flow rate (50mL/hour) by the Urine concentration (100mg/dL) and then divide by the Plasma concentration (60mg/dL). This gives 83.3 mL/hr. Since the question requires the answer in mL/min, you need to convert this by dividing by 60 (as 60 mins = 1hr), resulting in 1.4 mL/min.

To calculate Hematocrit (Hct) when given Renal Plasma Flow (RPF) and Renal Blood Flow (RBF), you use the formula Hct = 1 - (RBF / RPF). This formula takes into account the relationship between RBF and RPF to determine the Hematocrit level.

Filtered Load is calculated by multiplying the Glomerular Filtration Rate (GFR) by the Plasma concentration of the drug. Remember to pay attention to the units - GFR is in mL/min, and Plasma concentration is in mg/mL, so the resulting Filtered Load will be in mg/min.

The correct answer explains how increased plasma protein concentration and constriction of ureters actually lead to decreased FF, RPF, and GFR. The incorrect answers provide alternative scenarios that do not align with the physiological effects described in the correct answer.

When considering the filtration fraction (FF), it is essential to look at how the ratio of GFR to RPF changes. In the case of dehydration, although both GFR and RPF decrease, the reduction in RPF outweighs the decrease in GFR, leading to a decrease in FF. This is due to the fact that the RPF goes down more significantly than GFR, causing the FF to decrease despite the individual reductions in GFR and RPF.

The correct calculation for reabsorption rate involves subtracting the product of GFR and Px from the product of V and Ux. Likewise, the correct calculation for excretion rate involves subtracting the product of GFR and Px from the product of V and Ux.

FE(Na) is a measure of the proportion of sodium filtered by the kidney that is excreted in urine. It is primarily used to distinguish between different causes of acute renal failure. The correct formula to calculate FE(Na) is Excretion Rate / Filtration Rate.

The correct answer explains that Splay is the result of the heterogenicity of nephrons, causing some to excrete glucose earlier due to different TmG values. The incorrect answers provide alternative statements that do not accurately describe the concept of Splay.

ACE inhibitors work by inhibiting the enzyme that converts Angiotensin I to Angiotensin II, thereby reducing the levels of Angiotensin II in the body. This leads to decreased vasoconstriction, sodium reabsorption in the kidneys, and aldosterone synthesis, ultimately resulting in a lowering of blood pressure.

Digoxin is primarily secreted in the PROXIMAL convoluted tubules of the kidneys. Renal insufficiency can lead to increased toxicity of Digoxin, manifesting as prolonged PR interval, hyperkalemia, diarrhea, and vision changes.

The reabsorption of HCO3 is highest in the early proximal convoluted tubule due to the intricate process involving carbonic anhydrase and H+ secretion. This process is essential for maintaining acid-base balance in the body.