title: Circadian profile of peripheral hormone levels in Sprague-Dawley rats and in common marmosets (Callithrix jacchus).
abstract: OBJECTIVE
  in the present study, we report the circadian profiles of a wide panel of hormones measured in rats and common marmosets (Callithrix jacchus), under physiological conditions, paying special attention to minimising the stress imposed on the animals.
  
  
  METHODS
  blood collections were performed over a 24-hour period for the analysis of stress and pituitary hormones, metabolic markers and cytokines from male cannulated rats connected to a fully automatic system, and healthy marmosets in which gender differences were also evaluated.
  
  
  RESULTS
  in rats, a significant time effect was observed for corticosterone, prolactin (PRL), thyroid stimulating hormone (TSH), growth hormone, follicle-stimulating hormone, brain-derived neurotrophic factor, total ghrelin, insulin, leptin, insulin-like growth factor-1, adiponectin and interleukin-10. In marmosets, a significant time effect for cortisol, adrenocorticotropic hormone (ACTH), PRL and TSH, with gender effect for ACTH and PRL only, was observed. On the contrary, luteinizing hormone in the rat and active ghrelin, peptide YY, pancreatic polypeptide and gastric inhibitory polypeptide in the marmoset did not show any significant circadian variation.
  
  
  CONCLUSIONS
  the present work confirmed that, due to time-of-day dependent modulation of hormones, circadian rhythmicity is relevant in physiological studies and should also be taken into consideration when performing pharmacological studies.
authors.affiliation: Laboratory Animal Science Department, Medicine Research Center, Verona, Italy. SIMONE.BERTANI@APTUIT.COM
authors.forename: Simone
authors.initials: S
authors.lastname: Bertani
authors.forename: Lucia
authors.initials: L
authors.lastname: Carboni
authors.forename: Ana
authors.initials: A
authors.lastname: Criado
authors.forename: Francesca
authors.initials: F
authors.lastname: Michielin
authors.forename: Laura
authors.initials: L
authors.lastname: Mangiarini
authors.forename: Elena
authors.initials: E
authors.lastname: Vicentini
mesh_terms: D000818:Animals; D019208:Brain-Derived Neurotrophic Factor / Q000097:blood; D002144:Callithrix; D002940:Circadian Rhythm; D003345:Corticosterone / Q000097:blood; D016207:Cytokines / Q000097:blood*; D005260:Female; D006854:Hydrocortisone / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D008297:Male; D036361:Peptide Hormones / Q000097:blood*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013045:Species Specificity
chemical_list: D019208:Brain-Derived Neurotrophic Factor; D016207:Cytokines; D036361:Peptide Hormones; D007334:Insulin-Like Growth Factor I; D003345:Corticosterone; D006854:Hydrocortisone