Kidney Homeostasis: Blood Pressure, Fluid, and Electrolyte Regulation

All flashcards

What is calcitriol, and what role does the kidney play in producing it?

Calcitriol is the active form of vitamin D; the kidney produces it by hydroxylating calcidiol.

How does erythropoietin affect red blood cell production, and where is most circulating EPO made?

EPO stimulates red blood cell production in bone marrow; the kidneys produce about 85% of circulating EPO.

How do angiotensin II and aldosterone contribute to blood pressure regulation?

Angiotensin II causes vasoconstriction; aldosterone increases sodium reabsorption, with water following to support blood volume.

What is osmotic diuresis?

Excess glucose in urine draws water into the urine by osmosis, increasing water loss.

What is the current status of stem cell therapy for kidney injury?

It is a promising research area, but its safety and effectiveness are not established for routine treatment.

Quiz questions

1. In the RAAS, what does angiotensin-converting enzyme do?Answer: It converts angiotensin I into angiotensin II.
2. Which organ produces most circulating erythropoietin in humans?Answer: The kidneys
3. Why is potassium balance especially important for cardiac function?Answer: Potassium helps regulate cardiac muscle contraction and rhythm.
4. How can excess glucose in urine contribute to dehydration in uncontrolled diabetes mellitus?Answer: It draws water into the urine by osmosis, increasing water loss.
5. What is a key limitation of research on mesenchymal stem cells for kidney injury?Answer: Much of the research is from animals, and human evidence remains limited.