25. The Urinary System

The myogenic mechanism is triggered by changes in the stretch of the afferent arteriole. This is the direct result of:

The sympathetic nervous system releases _____________, which causes constriction of the afferent and efferent arterioles.

Angiotensin-II directly increases glomerular filtration pressure by _____________ the ___________ arteriole.

Fill in the blanks for the following statements:

a. When the GFR decreases, the macula densa releases chemicals to______ the afferent arteriole.

b. The sympathetic nervous system______ the blood vessels supplying the kidney _____ to the glomerular filtration rate.

c. The enzyme _____ is released by JG cells in response to a decrease in the GFR.

d. The enzyme ______ converts angiotensin-I to angiotensin-II.

e. Generally, angiotensin-II______ systemic blood pressure while _____ the GFR.

Describe the mechanisms of extrinsic regulation of GFR, and their physiological role.

Describe the mechanisms that contribute to renal autoregulation.

Which of the following is/are true about ADH?

a. It promotes obligatory water reabsorption

b. It is secreted in response to an increase in extracellular fluid osmolality

c. It causes insertion of aquaporins in the PCT

d. It promotes Na⁺ reabsorption

Mrs. Bigda, a 60-year-old woman, was brought to the hospital by the police after falling to the pavement. She is found to have alcoholic hepatitis. She is put on a salt- and protein-restricted diet and diuretics are prescribed to manage her ascites (accumulated fluid in the peritoneal cavity). How will diuretics reduce this excess fluid? Name and describe the mechanisms of action of three types of diuretics. Why is her diet salt-restricted?