title: Dilution kinetics of chemicals used for estimation of water content of body compartments in perinatal medicine.
abstract: Dilution kinetics of markers commonly used for estimation of body water content and distribution in perinatal medicine (p-aminohippurate, inulin, antipyrine, H218O, bromide, and T1824) were studied in pregnant and neonatal baboons. Amniotic fluid concentrations of p-aminohippurate and inulin decreased exponentially after intraamniotic injection of these markers; from 2-24 h after injection, concentrations decreased linearly on semilogarithmic plot (r = 0.96-1.00). Plasma concentrations of antipyrine decreased exponentially during the first 60 min after intravenous injection, then linearly from 1-5 h (r = 0.92-0.90). Plasma concentrations of 18O decreased linearly from 1-6 h after injection in three or four cases (r = 0.94-0.99). Plasma concentrations of bromide decreased during the first 2 h after injection, then stabilized for at least 3 h. Plasma concentrations of T1824 decreased linearly from 10-60 min after intravenous injection (r = 0.97-1.00). Then the decline became exponential until 5 h. These data allow us to make specific recommendations regarding the optimal time and method of amniotic fluid and blood sampling during body water studies.
authors.affiliation: Department of Pediatrics, Wayne State University School of Medicine, Detroit, Michigan.
authors.forename: Y W
authors.initials: YW
authors.lastname: Brans
authors.forename: D S
authors.initials: DS
authors.lastname: Andrew
authors.forename: E B
authors.initials: EB
authors.lastname: Dutton
authors.forename: C A
authors.initials: CA
authors.lastname: Schwartz
authors.forename: K D
authors.initials: KD
authors.lastname: Carey
mesh_terms: D000653:Amniotic Fluid / Q000032:analysis* / Q000378:metabolism; D000818:Animals; D000983:Antipyrine / Q000493:pharmacokinetics; D001834:Body Water / Q000032:analysis* / Q000378:metabolism; D001965:Bromides / Q000493:pharmacokinetics; D005070:Evans Blue / Q000493:pharmacokinetics; D005110:Extracellular Space / Q000032:analysis* / Q000378:metabolism; D005260:Female; D007444:Inulin / Q000493:pharmacokinetics; D010103:Oxygen Isotopes; D010215:Papio; D010953:Plasma Volume; D011247:Pregnancy; D010130:p-Aminohippuric Acid / Q000493:pharmacokinetics
chemical_list: D001965:Bromides; D010103:Oxygen Isotopes; D005070:Evans Blue; D007444:Inulin; D000983:Antipyrine; D010130:p-Aminohippuric Acid