2. in psychiatry, an unconscious defense mechanism in which unacceptable ideas, fears, and impulses are thrust out or kept out of consciousness. 3. gene r. enzyme repression interference, usually by the endproduct of a pathway, with synthesis of the enzymes of that pathway. gene repression the inhibition of gene transcription of an operon; in prokaryotes repressor binding to the operon is involved.
The ratio of intracellular to extracellular potassium determines neuromuscular and cardiovascular excitability, which is why serum potassium is normally regulated within a narrow range of 3.5 to 5.0 mmol/L. Dietary K+ intake is highly variable, ranging from as low as 40 mmol/day to more than 100 mmol/day.
Normal plasma potassium levels are between 3.5 and 5.0 meq/l; about 98% of the body's potassium is found inside cells, with the remainder in the extracellular fluid including the blood. Alternately, the NIH denotes 3.7â5.2 meq/l as a normal range. A low level of magnesium in the blood can also cause hypokalemia. 2  Magnesium is required for adequate processing of potassium. 3  This may become evident when hypokalemia persists despite potassium supplementation. 4  Other electrolyte abnormalities may also be present.