IMED3001 Lecture Notes - Lecture 6: Diuretic, Extracellular Fluid, Thiazide
L6: volume reduction diuretics: drugs that enhance the renal excretion of salt and water in hypertension, heart failure and other conditions of abnormal salt and water retention. Helps manage high bp and manage fluid overload. Loop of henle: water reabsorption is passive and requires an osmotic gradient established by na pumping. Therefore need a drug that prevents ion recovery and results in sodium and water excretion: we could tell someone to not drink as much water in order to decrease the removal of water but this could not work: If it"s a hot day, and one doesn"t drink as much water, therefore decreased bp and decreased iv volume and sympathetic system responsible for cerebral arterial flow and posture would not be equal to doing the task. It would lower the bp to treat heart failure but the person would be very thirsty, hypothalamus would be aware of the hypo-osmolarity- thirst = intolerable.