Role of kidney in regulation of Na and K
Kidney plays an important function in regulation the concentration of sodium and potassium in blood. A steroid hormone called aldosterone is secreted by the adrenal cortex in respond to rennin secreted by the kidney cells to stimulate potassium excretion by active reabsorption of sodium in distal and collecting ducts. Aldosterone increase active secretion of potassium in distal convoluted tubules and also stimulates the reabsorption of sodium on collecting ducts. Antidiuretic hormone also helps to regulate the concentration of sodium and potassium in blood. Antidiuretic hormone is secreted to conserve the amount of water to maintain the concentration of sodium in blood.
When there is an increase in the total body sodium, it will reduce the plasma volume and thus reduce the blood pressure (Widmaier, Raff & Strang 2001). The change in blood pressure will be detected by baroreceptor and initiate reflexes that influence the renal arterioles and tubules to reduce glomerular filtration rate (GFR).Renal cells secrete renin that indirectly cause adrenal cortex to increase aldosterone secretion. Increasing in aldosterone will stimulate cortical collecting duct to increase sodium reabsorption and reduces sodium excretion to regulate back the concentration of sodium in blood (Widmaier, Raff & Strang 2001).When there is an increase in blood potassium concentration, adrenal cortex will increase aldosterone secretion (Widmaier, Raff & Strang 2001). Increasing in aldosterone will stimulate cortical collecting ducts to increase potassium secretion and thus increase potassium excretion (Widmaier, Raff & Strang 2001). Critical value means that values that are outside the normal range to a degree that may constitute an immediate health risk to the individual or require immediate action of ordering physician. The critical value of sodium in blood is 160mmol/L (Massachusetts General Hospital 2013). If the sodium concentration in the blood is below then low critical value limit, the
When there is an increase in the total body sodium, it will reduce the plasma volume and thus reduce the blood pressure (Widmaier, Raff & Strang 2001). The change in blood pressure will be detected by baroreceptor and initiate reflexes that influence the renal arterioles and tubules to reduce glomerular filtration rate (GFR).Renal cells secrete renin that indirectly cause adrenal cortex to increase aldosterone secretion. Increasing in aldosterone will stimulate cortical collecting duct to increase sodium reabsorption and reduces sodium excretion to regulate back the concentration of sodium in blood (Widmaier, Raff & Strang 2001).When there is an increase in blood potassium concentration, adrenal cortex will increase aldosterone secretion (Widmaier, Raff & Strang 2001). Increasing in aldosterone will stimulate cortical collecting ducts to increase potassium secretion and thus increase potassium excretion (Widmaier, Raff & Strang 2001). Critical value means that values that are outside the normal range to a degree that may constitute an immediate health risk to the individual or require immediate action of ordering physician. The critical value of sodium in blood is 160mmol/L (Massachusetts General Hospital 2013). If the sodium concentration in the blood is below then low critical value limit, the