Reversal of the normal pattern of renal choline metabolism during uremia in rats.

Chronic uremia was produced in rats by removal of 85% of renal mass. 3 and 8 weeks later in the remnant kidneys the normal ratio of phosphorylcholine/betaine production from 14C-choline (1:2) was reversed. Phosphorylcholine production rose from 24.0 +/- 1.4 to 45.6 +/- 4.5 pmol/min/mg protein (p less than 0.001), and betaine production fell from 51.0 +/- 1.4 to 23.1 +/- 4.5 pmol/min/mg protein (p less than 0.001). This reversed pattern is also found in fetal and neonatal kidneys and during renal compensatory growth.