title: Zinc pharmacokinetic parameters in the determination of body zinc status in children.
abstract: OBJECTIVE
  Serum or tissue zinc concentrations are often used to assess body zinc status. However, all of these methods are relatively inaccurate. Thus, we investigated three different kinetic methods for the determination of zinc clearance to establish which of these could detect small changes in the body zinc status of children.
  
  
  METHODS
  Forty apparently healthy children were studied. Renal handling of zinc was investigated during intravenous zinc administration (0.06537 mg Zn/kg of body weight), both before and after oral zinc supplementation (5 mg Zn/day for 3 months). Three kinetic methods were used to determine zinc clearance: CZn-Formula A and CZn-Formula B were both used to calculate systemic clearance; the first is a general formula and the second is used for the specific analysis of a single-compartment model; CZn-Formula C is widely used in medical practices to analyze kinetic routine.
  
  
  RESULTS
  Basal serum zinc values, which were within the reference range for healthy children, increased significantly after oral zinc supplementation. The three formulas used gave different results for zinc clearance both before and after oral zinc supplementation. CZn-Formula B showed a positive correlation with basal serum zinc concentration after oral supplementation (R2=0.1172, P=0.0306). In addition, CZn-Formula B (P=0.0002) was more effective than CZn-Formula A (P=0.6028) and CZn-Formula C (P=0.0732) in detecting small variations in body zinc status.
  
  
  CONCLUSIONS
  All three of the formulas used are suitable for studying zinc kinetics; however, CZn-Formula B is particularly effective at detecting small changes in body zinc status in healthy children.
authors: Postgraduate Program in Health Sciences, Universidade Federal do Rio Grande do Norte, Natal, Brazil.
authors: S H L
authors: SH
authors: Vale
authors: Department of Nutrition, Universidade Federal do Rio Grande do Norte, Natal, Brazil.
authors: L D
authors: LD
authors: Leite
authors: Postgraduate Program in Health Sciences, Universidade Federal do Rio Grande do Norte, Natal, Brazil.
authors: C X
authors: CX
authors: Alves
authors: Postgraduate Program in Health Sciences, Universidade Federal do Rio Grande do Norte, Natal, Brazil.
authors: M M G
authors: MM
authors: Dantas
authors: Department of Chemical Engineering, Center for Industrial Technology, Universidade Federal do Rio Grande do Norte, Natal, Brazil.
authors: J B S
authors: JB
authors: Costa
authors: Department of Internal Medicine, Universidade de São Paulo, Ribeirão Preto, Brazil.
authors: J S
authors: JS
authors: Marchini
authors: Department of Statistics, Universidade Federal do Rio Grande do Norte, Natal, Brazil.
authors: M C
authors: MC
authors: França
authors: Department of Internal Medicine, Universidade Federal do Rio Grande do Norte, Natal, Brazil.
authors: J
authors: J
authors: Brandão-Neto
mesh_terms: D001823:Body Composition; D002648:Child; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D008297:Male; D008433:Mathematics; D008657:Metabolic Clearance Rate; D009752:Nutritional Status; D015032:Zinc / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*
chemical_list: D015032:Zinc