title: Agarose gel electrophoresis of cerebrospinal fluid proteins of dogs after sample concentration using a membrane microconcentrator technique.
abstract: BACKGROUND
  Cerebrospinal fluid (CSF) is produced in the cerebral ventricles through ultrafiltration of plasma and active transport mechanisms. Evaluation of proteins in CSF may provide important information about the production of immunoglobulins within the central nervous system as well as possible disturbances in the blood-brain barrier.
  
  
  OBJECTIVE
  The objective of this study was to measure the concentration and fractions of protein in CSF samples using a membrane microconcentrator technique followed by electrophoresis, and to compare the protein fractions obtained with those in serum.
  
  
  METHODS
  CSF samples from 3 healthy dogs and 3 dogs with canine distemper virus infection were concentrated using a membrane microconcentrator having a 0.5 to 30,000 d nominal molecular weight limit (Ultrafree, Millipore, Billerica, MA, USA). Protein concentration was determined before and after concentration. Agarose gel electrophoresis was done on concentrated CSF samples, serum, and serial dilutions of one of the CSF samples.
  
  
  RESULTS
  Electrophoretic bands were clearly identified in densitometer tracings in CSF samples with protein concentrations as low as 1.3 g/dL. The higher CSF protein concentration in dogs with distemper was mainly the result of increased albumin concentration.
  
  
  CONCLUSIONS
  The microconcentrating method used in this study enables characterization of the main protein fractions in CSF by routine electrophoresis and may be useful for interpreting the underlying cause of changes in CSF protein concentrations.
authors.affiliation: Department of Veterinary Clinical and Surgery, Faculdade de Ciências Agrárias e Veterinárias, UNESP Câmpus de Jaboticabal, São Paulo, Brazil. santana@fcav.unesp.br
authors.forename: Fernanda Gomes Velasque
authors.initials: FG
authors.lastname: Gama
authors.forename: Aureo Evangelista
authors.initials: AE
authors.lastname: Santana
authors.forename: Eugênio de Campos
authors.initials: Ede C
authors.lastname: Filho
authors.forename: Cláudia Aparecida da Silva
authors.initials: CA
authors.lastname: Nogueira
mesh_terms: D000818:Animals; D002556:Cerebrospinal Fluid Proteins / Q000032:analysis* / Q000378:metabolism*; D004216:Distemper / Q000134:cerebrospinal fluid; D004285:Dogs; D004587:Electrophoresis, Agar Gel / Q000379:methods* / Q000662:veterinary*; D005260:Female; D008297:Male
chemical_list: D002556:Cerebrospinal Fluid Proteins