title: [Effects of lipopolysaccharide and dexamethasone on the expression of Kisspeptin/GPR54 in mouse hypothalamus].
abstract: OBJECTIVE
  To evaluate the effects of lipopolysaccharide (LPS) and dexamethasone on function of hypothalamus-pituitary-testis axis and to explore the possible underlying mechanisms.
  
  
  METHODS
  LPS (100 μg/kg), dexamethasone (DEX, 1 mg/kg) and phosphate buffer saline (PBS) were injected subcutaneously into castrated mice (n=5 in each group) for 4 weeks. The expression of Kisspeptin and its receptor GPR54 in hypothalamus were measured by immunohistochemistry, and plasma luteinizing hormone (LH) were measured by chemiluminescence immunoassay.
  
  
  RESULTS
  After LPS and DEX were administered for 4 weeks, the LH level in LPS group and DEX group was (1.79±0.74) U/L and (2.19±0.60) U/L, respectively, which were lower than PBS group (4.87±1.25) U/L (all P<0.01). In LPS group, after treatment, the kisspeptin immunohistochemistry index in hypothalamus was 4.2±1.1, which was lower than the control group (10.2±1.6, P<0.05). The GPR54 immunohistochemistry index in hypothalamus was 3.6±0.5, which was lower than PBS group (6.2±1.8, P<0.05). In DEX group, the expressions of kisspeptin and GPR 54 in hypothalamus did not change after treatment.
  
  
  CONCLUSIONS
  LPS may downregulate function of hypothalamus-pituitary-testis axis through Kisspeptin/GPR54 system. Dexamethasone could suppress function of gonadal axis as well, while the underlying mechanism is still unclear.
authors.affiliation: Department of Endocrinology, Peking Union Medical College Hospital, Beijing 100730, China.
authors.forename: Jiangfeng
authors.initials: J
authors.lastname: Mao
authors.forename: Bingkun
authors.initials: B
authors.lastname: Huang
authors.forename: Zhao
authors.initials: Z
authors.lastname: Sun
authors.forename: Qin
authors.initials: Q
authors.lastname: Han
authors.forename: Min
authors.initials: M
authors.lastname: Nie
authors.forename: Xueyan
authors.initials: X
authors.lastname: Wu
mesh_terms: D000818:Animals; D003907:Dexamethasone / Q000494:pharmacology*; D007031:Hypothalamus / Q000187:drug effects / Q000378:metabolism*; D007150:Immunohistochemistry; D059648:Kisspeptins / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000494:pharmacology*; D007986:Luteinizing Hormone / Q000097:blood; D008297:Male; D051379:Mice; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism*; D000074502:Receptors, Kisspeptin-1
chemical_list: C492248:Kiss1r protein, mouse; D059648:Kisspeptins; D008070:Lipopolysaccharides; D043562:Receptors, G-Protein-Coupled; D000074502:Receptors, Kisspeptin-1; D003907:Dexamethasone; D007986:Luteinizing Hormone