Open Access11 C‐Methionine Kinetics in Pregnant Rhesus Monkeys Studied by Positron Emission Tomography: A New Approach to Feto‐Maternal Metabolism
Author(s) -
Berglund Lars,
Halldin Christer,
Lilja Anders,
Lindberg Bo S.,
Låndqvist Hans,
Långström Bengt,
Malmborg Petter,
Nägren Kjell,
Stälnacke CarlGÖRan
Publication year - 1984
Publication title -
acta obstetricia et gynecologica scandinavica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.401
H-Index - 102
eISSN - 1600-0412
pISSN - 0001-6349
DOI - 10.3109/00016348409155554
Subject(s) - placenta , fetus , urine , amniotic fluid , methionine , positron emission tomography , metabolism , positron , medicine , amino acid , endocrinology , nuclear medicine , pregnancy , biochemistry , chemistry , biology , genetics , physics , quantum mechanics , electron
. By use of Positron Emission Tomography (PET), dynamic studies of the metabolism within the fetomaternal unit can be performed using various tracers. Many compounds like amino acids, carbohydrates, fatty acids and drugs can be labelled with 11 C and used as tracers. 11 C‐labelled L‐ or D‐methinonine was injected intravenously into pregnant Rhesus monkeys. The distribution of the radioactivity in maternal muscles, aorta, placenta and the liver of the fetus was quantitively estimated as a function of time. Simultaneously blood, urine and amniotic fluid samples were analysed for 11 C‐activity. The distribution of 11 C between the high and the low molecular fraction of plasma (MW>5000) was studied after gel filtration. Both when 11 C‐L‐ and D‐methionine were given, the radioactivity rapidly crossed the placenta and was accumulated in the fetal liver. In the 11 C‐L‐methionine experiments, about 70 per cent of the radioactivity in plasma was found in the high molecular fraction one hour after injection. A greater part of 11 C‐D‐compared to 11 C‐L‐activity was excreted in the urine.