期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1991
卷号:88
期号:14
页码:6053-6057
DOI:10.1073/pnas.88.14.6053
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:We have used volume-localized 1H NMR spectroscopy to detect and measure changes in medullary trimethylamines (TMAs) in the human kidney in vivo. Localized water-suppressed 1H spectra were collected from a volume of interest located within the renal medulla by using a stimulated echo-based localization scheme. The principal resonances in the medullary 1H spectrum were residual water (4.7 ppm), lipid (0.9-1.4 ppm), and TMAs (3.25 ppm). The TMA line width was 7-15 Hz before filtering, and the signal-to-noise ratio was 40:1. In four normal volunteers, 15 hr of dehydration led to a significant increase in urine osmolality and decrease in body weight and an increase in medullary TMAs. A subsequent water load [20 ml.(kg of body weight)-1] caused a transient water diuresis, a return to euvolemic body weight, and a significant reduction in medullary TMAs within 4 hr. These results suggest that TMAs may play an osmoregulatory role in the medulla of the normal human kidney.