title: [Change of serum leptin and leptin receptors immunoreactivity in the brain following intraoral infusions of chemical solutions in rats].
abstract: OBJECTIVE
  To determining whether the level of serum leptin altered and whether the expression of leptin receptor immunoreactivity changed following taste stimuli.
  
  
  METHODS
  After intraoral infusions of chemical solutions, which included 3 mol/L sucrose, 5 mmol/L sodium saccharin, 0.1 mol/L NaCl, 0.01 mol/L HCl, 1 mmol/L quinine H2SO4 and 0.1 mol/L monosodium glutamate, serum leptin concentration were measured by using rat leptin RIA kit. Immunohistochemistry ABC method was used for brain sections with high-specify-goat antiserum against leptin receptors.
  
  
  RESULTS
  Comparing with the control group (intraoral infusion of distilled water), the level of serum leptin only in sweet group (sucrose an d saccharin) raised (P < 0.05). Many neuronal cell bodies and dendritic processes showed leptin receptors immunoreactivity (LR-IR) in many brain regions, such as amygdala, hypothalamus, parabrachial nucleus and nucleus of the solitary tract, which had intense relationship with taste and feeding. But the number of positive-stained cells showed no difference in aforementioned brain regions between the taste stimuli group and the control group.
  
  
  CONCLUSIONS
  After intraoral stimuli of sweet substances, the serum leptin concentration increased. LR-IR cells exist in amygdala which plays a critical role in the initiation and guidance of feeding. This findings led us study possible effects of leptin on taste responses. Probably, leptin influences food intake through the sense of taste.
authors.affiliation: Department of physiology, School of medicine, Xi'an Jiaotong University, Xi'an 710061, China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Han
authors.forename: Jian-qun
authors.initials: JQ
authors.lastname: Yan
authors.forename: Zhi-chao
authors.initials: ZC
authors.lastname: Wei
mesh_terms: D000818:Animals; D001921:Brain / Q000502:physiology*; D004435:Eating; D005260:Female; D020738:Leptin / Q000097:blood* / Q000378:metabolism*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D054411:Receptors, Leptin / Q000097:blood*; D013649:Taste
chemical_list: D020738:Leptin; D054411:Receptors, Leptin