Influence of hormones on renal physiology

Question 1

List 7 hormones that influence the renal system

Answer 1

ADH (Vasopressin)
Aldosterone
Renin
Atrial Natriuretic Peptide (ANP)
Parathyroid Hormone (PTH)
Erythropoietin (EPO)
Natriuretic Hormones (eg. BNP)

Question 2

Explain the role of ADH

Answer 2

• increases water permeability in the renal collecting ducts to increase water reabsorption
• more concentrated urine / reduced urine output
• prevents dehydration

Question 3

Where is ADH produced and what triggers its release?

Answer 3

produced by the hypothalamus
released by the posterior pituitary gland
central osmoreceptors detect an increase in plasma osmolarity / a decrease in blood volume

Question 4

How does ADH increase water reabsorption in the renal tubules?

Answer 4

• When low blood volume or high blood osmolarity is detected, central osmoreceptors
  — in the posterior pituitary are triggered to secrete ADH
  — from the hypothalamus
• ADH regulates water reabsorption in the distal convoluted tubule and collecting duct
  — by Increasing water permeability of the collecting duct
  — Results in more water being reabsorbed into the bloodstream
• more ADH = more water reabsorption = blood volume increases, and blood osmolarity decreases = lower sodium concentration in the blood.

Question 5

what would happen in the absence of ADH?

Answer 5

higher volume of dilute urine
dehydration

Question 6

Explain the role of Aldosterone

Answer 6

• increases sodium reabsorption in the distal CT and collecting duct
• increases potassium excretion
• raises blood pressure and restores electrolyte balance

Question 7

where is aldosterone produced and what triggers its release?

Answer 7

produced by the adrenal cortex
released when _ detects low blood pressure / low sodium levels

Question 8

Explain the role of renin

Question 9

where is renin produced and what triggers its release?

Answer 9

Produced by specialised granule cells of the juxtaglomerular apparatus.

Question 10

Explain the role of ANP (Atrial Natriuretic Peptide)

Question 11

where is ANP produced and what triggers its release?

Question 12

Explain the role of PTH (Parathyroid Hormone)

Question 13

where is PTH produced and what triggers its release?

Question 14

Explain the role of EPO (Erythropoietin)

Question 15

where is EPO produced and what triggers its release?

Question 16

Explain the role of natriuretic hormones

Question 17

where are natriuretic hormones produced and what triggers its release?