title: Chronobiology of urinary citrate excretion amongst stone-formers and healthy males from north western India.
abstract: Urinary citrate excretion was estimated colorimetrically from urine samples collected every 3 h for 24 h from 25 healthy adult males (non-stone formers; mean age 39 +/- 7 years) and 25 male patients suffering from calcium nephrolithiasis (stone formers; mean age 41 +/- 6 years). The 24 h citrate excretion was 2.47 +/- 0.65 mmol in non-stone formers and 2.02 +/- 0.71 mmol in stone formers. This difference was not significant. However, cosinor rhythmometry revealed a significant circadian rhythmicity in urinary citrate excretion in the healthy males which was absent in the stone formers; the amplitude was 0.06 mmol in non-stone formers and 0.017 mmol in stone formers. The acrophase was located at 14:25 h in non-stone formers and at 23:30 h in stone formers.
authors.affiliation: Department of Biochemistry, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
authors.forename: D
authors.initials: D
authors.lastname: Wangoo
authors.forename: S K
authors.initials: SK
authors.lastname: Thind
authors.forename: G S
authors.initials: GS
authors.lastname: Gupta
authors.forename: R
authors.initials: R
authors.lastname: Nath
mesh_terms: D000328:Adult; D002129:Calcium Oxalate / Q000652:urine*; D002940:Circadian Rhythm / Q000502:physiology*; D002951:Citrates / Q000652:urine*; D019343:Citric Acid; D006801:Humans; D007194:India / Q000453:epidemiology; D007669:Kidney Calculi / Q000453:epidemiology / Q000503:physiopathology / Q000652:urine*; D008297:Male
chemical_list: D002951:Citrates; D002129:Calcium Oxalate; D019343:Citric Acid