title: An optimised methodology for the neurobehavioural assessment in rodents.
abstract: BACKGROUND
  The most widely used test to identify undesired effects of drugs on the central and the peripheral nervous system is the neurobehavioural observation battery adapted from that first described by Irwin in mice. As a neurobehavioural assessment is based on observations; thus, all factors involved need to be controlled and standardised to make the data collected objective, reproducible, reliable and predictive of safety liabilities.
  
  
  METHODS
  An observation battery comprising 58 signs with assigned full details of numerical scores was defined, and a standard design with associated recording, presenting and analysing data system was established. Validation studies were conducted with chlorpromazine, amphetamine, diazepam or clonidine given orally to rats or mice, in order to assess if this methodology could clearly differentiate the profile of effects produced by these compounds. The analysis of data from 80 control rats allowed for the assessment of the normal behaviour in order to characterise the inter-individual, daytime-related variability and the habituation of animals to the procedure.
  
  
  RESULTS
  The reference compounds induced their typical and expected transient effects on neurobehaviour, observed both in the home cage and open-arena, and on body temperature. In particular, amphetamine induced a stimulation of the nervous system activities and marked hyperthermia. Chlorpromazine, diazepam and clonidine induced depressive, anxiolytic or sedative effects associated with hypothermia. The analysis of data collected in control animals allowed for the identification of 6 signs which scored differently from the assigned normality at the first handling occasion due to the characteristic fear reactions to the unknown, and 9 signs at 8 h post-dose due to the animal's habituation to experimental conditions and handling.
  
  
  CONCLUSIONS
  The neurobehavioural changes expected by reference compounds administration were detected. These results confirm that by using this methodology the normal behaviour of the rat and the mouse, the daytime-related variability and the habituation of animals can be characterised, allowing a refined, reliable and reproducible neurobehavioural assessment of test substances in rodents.
authors.affiliation: Safety Pharmacology, Safety Assessment Department, GlaxoSmithKline R&D Centre, Via Fleming 4, VERONA (37135), Italy. elena.2.moscardo@gsk.com
authors.forename: Elena
authors.initials: E
authors.lastname: Moscardo
authors.forename: Anne
authors.initials: A
authors.lastname: Maurin
authors.forename: Roberto
authors.initials: R
authors.lastname: Dorigatti
authors.forename: Pascal
authors.initials: P
authors.lastname: Champeroux
authors.forename: Serge
authors.initials: S
authors.lastname: Richard
mesh_terms: D000284:Administration, Oral; D000367:Age Factors; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects / Q000502:physiology*; D001831:Body Temperature / Q000187:drug effects; D002490:Central Nervous System / Q000187:drug effects / Q000502:physiology*; D000697:Central Nervous System Stimulants / Q000008:administration & dosage / Q000494:pharmacology; D002746:Chlorpromazine / Q000008:administration & dosage / Q000494:pharmacology; D003000:Clonidine / Q000008:administration & dosage / Q000494:pharmacology; D003913:Dextroamphetamine / Q000008:administration & dosage / Q000494:pharmacology; D003975:Diazepam / Q000008:administration & dosage / Q000494:pharmacology; D006185:Habituation, Psychophysiologic / Q000187:drug effects; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D009460:Neurologic Examination / Q000379:methods; D009483:Neuropsychological Tests / Q000592:standards / Q000706:statistics & numerical data*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results; D013997:Time Factors
chemical_list: D000697:Central Nervous System Stimulants; D003000:Clonidine; D003975:Diazepam; D003913:Dextroamphetamine; D002746:Chlorpromazine