title: Long-term effects on bone of postnatal immunization against GHRH in female and male rats.
abstract: The effects of neonatal passive immunization against GHRH on bone was examined in male and female rats. Pups were treated subcutaneously with GHRH-antiserum (GHRH-Ab) from day 1 to day 10 of age. Bone mineral content (BMC) and bone mineral density (BMD) were evaluated at monthly intervals until 7 months. Markers of bone resorption (urinary lysylpyridinoline, LP), bone formation (serum osteocalcin, OC) and serum IGF-I were measured at 2, 3 and 7 months. In male rats, GHRH-Ab did not modify BMC and BMD when compared with controls. In contrast, female rats demonstrated lower whole body and femoral BMC and BMD from 2 to 7 months of age. Reduced bone growth in the females was associated with lower IGF-I levels than controls at 2 and 3 months of age, whereas in males IGF-I titers did not change during the period of the study. LP excretion was higher in GHRH-Ab-treated rats at 2 and 3 months in both sexes. In females, no difference in OC values was recorded, whereas in GHRH-Ab-treated males, there was an increase in OC levels at 2 and 3 months. These data indicate that transient GHRH deprivation induces an osteopenic effect in female rats which is not evident in male rats.
authors.affiliation: Department of Pharmacology, Chemotherapy and Medical Toxicology, Centre of Excellence of Neurodegenerative Diseases, University of Milan, Via Vanvitelli 32, Italy. Valeria.Sibilia@unimi.it
authors.forename: V
authors.initials: V
authors.lastname: Sibilia
authors.forename: A E
authors.initials: AE
authors.lastname: Rigamonti
authors.forename: F
authors.initials: F
authors.lastname: Pagani
authors.forename: N
authors.initials: N
authors.lastname: Lattuada
authors.forename: F
authors.initials: F
authors.lastname: Guidobono
authors.forename: W B
authors.initials: WB
authors.lastname: Wehrenberg
authors.forename: E E
authors.initials: EE
authors.lastname: Muller
authors.forename: C
authors.initials: C
authors.lastname: Netti
mesh_terms: D000596:Amino Acids / Q000652:urine; D000818:Animals; D000831:Animals, Newborn; D015415:Biomarkers / Q000097:blood / Q000652:urine; D001835:Body Weight / Q000187:drug effects; D015519:Bone Density / Q000187:drug effects; D016723:Bone Remodeling / Q000187:drug effects; D001842:Bone and Bones / Q000378:metabolism / Q000502:physiology*; D005260:Female; D013007:Growth Hormone-Releasing Hormone / Q000276:immunology / Q000502:physiology*; D007106:Immune Sera / Q000494:pharmacology; D007116:Immunization, Passive; D007334:Insulin-Like Growth Factor I / Q000032:analysis; D008297:Male; D008903:Minerals / Q000378:metabolism; D015675:Osteocalcin / Q000097:blood; D051381:Rats; D017207:Rats, Sprague-Dawley; D012723:Sex; D012741:Sexual Maturation / Q000187:drug effects
chemical_list: D000596:Amino Acids; D015415:Biomarkers; D007106:Immune Sera; D008903:Minerals; D015675:Osteocalcin; D007334:Insulin-Like Growth Factor I; C036020:deoxypyridinoline; D013007:Growth Hormone-Releasing Hormone