A concentrated solution of sodium chloride was intravenously injected to an animal. This caused decreased reabsorption of sodium ions in the renal tubules. It is the result of the following changes of hormonal secretion:

Answer options

1. Vasopressin increase
2. Aldosterone increase
3. Reduction of atrial natriuretic factor
4. Vasopressin reduction
5. Aldosterone reduction

Explanation

Aldosterone is a steroidal hormone produced by the outer section (zona glomerulosa) of the adrenal cortex in the adrenal gland, and acts on the distal tubules and collecting ducts of the kidney to cause the conservation of sodium, secretion of potassium, increased water retention and increased blood pressure. The overall effect of aldosterone is to increase the reabsorption of ions and water in the kidney. Therefore, decreased reabsorption means aldosterone reduction.