Open AccessUnreliability of tritiated cholesterol: studies with [1,2-3H]-cholesterol and [24,25-3H]cholesterol in humans.
Author(s) -
Nicholas O. Davidson,
E. H. Ahrens,
H. Leon Bradlow,
Donald J. McNamara,
Thomas S. Parker,
Paul Samuel
Publication year - 1980
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.77.4.2255
Subject(s) - cholesterol , in vivo , in vitro , chemistry , cholesterol synthesis , tritium , medicine , biochemistry , endocrinology , biology , microbiology and biotechnology , enzyme , physics , reductase , nuclear physics
Over the past 18 months different lots of [1,2-3H]cholesterol and [24,25-3H]cholesterol were found to be radiochemically acceptable by conventional chemical and other in vitro tests, yet, when co-administered with [4-14C]cholesterol to human subjects, an abrupt fall in the 3H/14C specific activity ratio in plasma cholesterol was discovered in every case. We have concluded that all batches of [3H]cholesterol should be regarded as radiochemically unreliable unless they are shown to behave identically in all respects to [4-14C]cholesterol in an appropriate in vivo assay system.