ABSTRACT
Adult rats were treated for ten days with capsaicin or with NaCl 0.9% directly injected into the lateral cerebral ventricles through a surgically implanted cannula. A third group of rats was implanted with the same cannula but did not receive any treatment. The food intake and the body weight were recorded for at least six weeks after stopping the treatment. The animals were always kept at constant ambient temperature of 22 °C. The body weight of the capsaicin-treated group was reduced by the treatment, and showed a regular but lower degree of recovery trend than the control groups after the treatment period. In fact the capsaicin treated animals never reached the body weight of the controls. Nevertheless, food intake did not significantly vary after the capsaicin treatment. On the basis of these and previous findings, we can assume that capsaicin injected into the cerebral ventricles to rats kept at constant ambient temperature can acts on hypothalamic neurons, but a permanent action on metabolic pathways can not be excluded.
Subject(s)
Body Weight/drug effects , Capsaicin/pharmacology , Sensory System Agents/pharmacology , Weight Gain/drug effects , Animals , Body Temperature , Body Temperature Regulation , Capsaicin/administration & dosage , Eating/drug effects , Infusions, Intraventricular , Male , Rats , Rats, Wistar , Sensory System Agents/administration & dosage , TemperatureABSTRACT
BACKGROUND: During application of orthodontic force on the tooth, various molecular parameters associated with tissue remodeling are changed. IGF-I is a regulatory protein produced during periodontal regeneration. IGF binding proteins-3 (IGFBP-3), a specific IGF-I binding protein, is the major regulatory factor of IGF-I activity. OBJECTIVES: We tested the hypothesis that changes in the IGF-I/ IGFBP-3 system occur during fixed force application to the tooth and that these changes are detectable in the gingival crevicular fluid (GCF). METHODS: IGFBP-3 and IGF-I secretion into gingival crevicular fluid (GCF) was analyzed by Western blotting and immunoradiometric assay (IRMA), respectively, in GCF of 6 healthy subjects just prior to and during orthodontics treatment using fixed appliances. RESULTS: We observed a significant time-dependent decrease of IGFBP-3 content in GCF during orthodontic treatment (4 h and 10 days). Reduction in levels of intact, glycosylated 47 kDa form of IGFBP-3 was associated with its degradation and the appearance of intermediate breakdown products. IGF-I levels were significantly increased 4 h after application of orthodontic force, while they were significantly reduced 10 days after the start of treatment. CONCLUSIONS: IGFBP-3 secretion into GCF and its molecular structure are modified by the fixed force of orthodontic treatment. Alterations in IGFBP-3 appear to be unrelated to the binding to IGF-I, suggesting an IGF-independent role of this binding protein in tooth movement.
