Accelerated uptake of an intravenously administered dose of choline chloride in choline-deficient humans
✍ Scribed by Nancy F. Sheard; Kerry-Ann da Costa; Steven H. Zeisel
- Publisher
- Elsevier Science
- Year
- 1994
- Tongue
- English
- Weight
- 484 KB
- Volume
- 5
- Category
- Article
- ISSN
- 0955-2863
No coin nor oath required. For personal study only.
✦ Synopsis
The role of choline in the human diet continues to be debated, in part due m the lack of an appropriate assessment technique, lnfi~rmation regarding the turnover q[ this nutrient in various body pools in humans is lacking. An intravenous inJusion of (&methyl)-choline chloride was administered over 1 hour to human subjects fed either a choline-containing (5 mmoles/dav choline chloride) or a choline-deficient diet fi~r 3 weeks. Blood samples were collected during the infusion and fi)r 1 hour postinfusion. Plasma levels of choline, (d,methyl)choline, and phosphatidylcholine were measured. The uptake of (d~methyl)-choline from plasma was calculated by nonlinear regression analysis. In control subjects (n = 4), the half-life of (d~methyl)-choline in plasma was 7.0 ++_ 0.85 minutes, while in deficient subjects (n = 6) it was 3.5 +_ 0.42 minutes (P < 0.004). Extracellular choline pools were also decreased in deficient subjects (mean +_ SEM; control: 2.6 ++_ 0.2 mmoles; deficient: 2.0 ± 0.2 mmoles, P < 0.05). The rate of appearance of unlabeled choline into the plasma was unaffected by the level of dietary choline. We conclude that intravenously administered choline chloride is cleared more rapidly in humans fed a choline-deficient diet than in control subjects, and that choline de~'cien~T decreases choline pools in the body. Our results also indicate that an intravenous load test, similar to the one used in these studies, may be use[ul as a method q[ measuring choline nutriture.