Which one of the following four secretions is correctly matched with its source, target and nature of action?

• Secretion	Source	Target	Action
  Gastrin	Stomach lining	Oxyntic cells	Production of HCl

• Inhibin

  Sertoli cells

  Hypothalamus

  Inhibition of secretion of gonadotropin releasing hormone

• Enterokinase

  Duodenum

  Gall bladder

  Release of bile juice

• Atrial Natiuretic Factor (ANF)

  Sinu atrial node (SAN) M- cells of Atria

  Juxta- glomerular apparatus (JGA)

  Inhibition of release of renin

D.

Atrial natriuretic factor (ANF) is released by wails of the cardiac atrium in response to high sodium concentration, high extracellular fluid volume, or high blood volume. It then acts via various mechanisms to excrete Na, and to cause vasodilation in the circulatory system. It also decreases Na resorption in the renal distal convoluted tubule and cortical collecting duct. It also inhibits renin secretion.

Gastrin is a polypeptide hormone produced by the enteroendocrinc cells of the stomach. It plays an important role in the control of gastric acid secretion.

Inhibin hormone is secreted from corpus luteum, placenta and testes. It supplements the effect of excess sex hormones for depressing gonadotrophic activity (FSH, LH, ICSH) target of inhibin is anterior lobe of pituitary.

Duodenal enterokinase converts trypsinogcn to activate trypsin which, in turn, activates the other pancreatic enzymes.