ANATOMY

Detailed explanation-1: -Renin is secreted by juxtaglomerular cells located in the afferent arteriole. At the cellular level, renin secretion is mediated by the fusion of renin-containing granules with the luminal membrane of the cell.

Detailed explanation-2: -Juxtaglomerular cells are sensors that manufacture and release the hormone-enzyme renin in response to minute changes in BP and the composition and volume of the extracellular fluid.

Detailed explanation-3: -How is renin released? Renin is released into your bloodstream when your blood pressure drops too low or when there’s not enough sodium in your body. Specifically, renin secretion happens when: Baroreceptors (pressure-sensitive receptors) in your arterial vessels detect low blood pressure.

Detailed explanation-4: -Mechanism of Action. Increased renin release from the juxtaglomerular cells is caused by several conditions: reduction in renal blood flow from heart failure, blood loss, hypotension or ischemia of the kidneys, sodium diuresis (excessive sodium loss in urine), and beta-adrenergic stimulation.