Increased renal tubular sodium reabsorption: sympathetic nerve activation
Activation of the sympathetic nervous system, if severe, can cause a decrease in sodium and water excretion by renal vasoconstriction, reducing glomerular filtration rate.
Because of the importance of maintaining an accurate balance between glomerular filtration and tubular reabsorption, many nerves, hormones and local mechanisms are involved in the regulation of reuptake. absorption of the renal tubules as well as glomerular filtration. The most striking importance of reabsorption is that the reabsorption of some substances can occur independently of others, especially in the presence of hormones.
Activation of the sympathetic nervous system, if severe, can cause a decrease in sodium and water excretion by renal vasoconstriction, reducing glomerular filtration rate. With mild sympathetic activation, however, decreases sodium and water excretion due to increased reabsorption of sodium and water in the proximal tubule, the up segment of the Henle dial, which may include the distal tubule. This phenomenon occurs due to the activation of α-adrenergic receptors in renal tubular epithelial cells.
The sympathetic nervous system also stimulates the secretion of renin and angiotensin II, increasing efficiency in water and sodium reabsorption as well as reducing their secretion.