Question

The increased blood pressure, decrease in the water content of urine and promotion of contraction of smooth muscles is brought about by

• A. Oxytocin and ACTH
• B. Vasopressin and ACTH
• C. Vasopressin and ADH
• D. Vasopressin and oxytocin

Answer 1

The correct option is D Vasopressin and oxytocin

Vasopressin (antidiuretic hormone; ADH) and oxytocin are produced by hypothalamus but stored and released in to blood stream via posterior pituitary. ADH is released in response to increased blood ion concentration, increased urine production and the resultant fall in blood pressure. ADH targets nephrons in kidney to increase water reabsorption and thereby decreasing water content in urine and increasing the blood pressure. Oxytocin (OT) stimulates uterine muscle contraction during child birth and initiates release of milk by mammary gland. This makes option D correct. Options A and B are incorrect as adrenocorticotropic hormone (ACTH) is secreted by anterior pituitary gland and targets adrenal cortex to produce its hormones which are namely mineralocorticoids and the glucocorticoids. Option C is incorrect as vasopressin and ADH are synonymous. Correct answer is D.