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.
Physiology of Potassium Handling. Potassium (K+) is the most abundant cation in the body. About 90% of total body potassium is intracellular and 10% is in extracellular fluid, of which less than 1% is composed of plasma.
There is a significant difference between the concentrations of sodium and potassium ions inside and outside the cell. The concentration of sodium ions is considerably higher in the extracellular fluid than in the intracellular fluid. The converse is true of the potassium ion concentrations inside and outside the cell.