piperidines and Femoral-Fractures

Neurologic injury and selective blockage of sensory nerve endings is associated with impaired fracture healing, however, the role of specific neurotransmitters has not been sufficiently investigated. Our aim was to investigate the impact of specific Substance P-receptor blockage on fracture healing, since the neuropeptide Substance P has both neurogenic and osteogenic activity. After intramedullary stabilization, an isolated femur fracture was induced in 72 Sprague-Dawley rats. In the NK1-R group, the neurokinin-1-tachykinin receptor for substance P was blocked by a specific antagonist (SR140333) for the first two weeks after fracture induction. The control group only received vehicle. Gene-expression, histology, micro-computed tomography, and biomechanical tests were performed. NK1-receptor blocking suppressed osteocalcin expression at one week, collagen 1A2 expression at one and two weeks and collagen 2A1 expression at 2 weeks after fracture induction. Biomechanical testing revealed a significant reduction in maximal load to failure in the NK1-R group at 6 weeks (69.78 vs. 155.45 N, p = 0.029) and at 3 months (72.50 vs.176.33 N, p = 0.01) of fracture healing. Blocking the NK1-receptor suppresses gene expression in and reduces biomechanical strength of healing bone. Therefore, we assume a potential therapeutic relevance of Substance P in cases of disturbed fracture healing.

Topics: Animals; Collagen Type I; Collagen Type II; Disease Models, Animal; Femoral Fractures; Fracture Healing; Gene Expression Regulation, Neoplastic; Male; Neurokinin-1 Receptor Antagonists; Osteocalcin; Piperidines; Quinuclidines; Rats; Rats, Sprague-Dawley; Substance P; Treatment Outcome

In patients with osteogenesis imperfecta (OI), general anesthetic management should be carefully implemented in consideration of difficult intubation and the potential risks of cervical or mandibular fracture associated with tracheal intubation, bone fracture during postural changes, and respiratory dysfunction due to thoracic deformity. To prevent temperature elevation, moreover, many reports have recommended anesthetic management using total intravenous anesthesia (TIVA) rather than inhalation anesthetics, which contribute to temperature elevation. In an 8-year-old boy with type II (fatal type) OI (height, 81 cm; body weight, 12.4 kg), we performed general TIVA with remifentanil and propofol, using a laryngeal mask airway for airway management. All possible intra- and postoperative complications were effectively prevented, and the remifentanil requirement was high, as shown by a mean dose of 0.36 microg x kg(-1) x min(-1).

Topics: Anesthesia, Intravenous; Anesthetics, Intravenous; Child; Femoral Fractures; Humans; Infusions, Intravenous; Laryngeal Masks; Leg; Male; Osteogenesis Imperfecta; Piperidines; Remifentanil; Respiration, Artificial

As shown in earlier studies, the lodgement of circulating tumour cells in the lungs is reduced by thrombocytopenia in both normal and traumatized rats. Other experiments have shown that thrombocytopenia and antiserotonin treatment with ketanserin, which has a selective effect on 5-HT2 receptors, decrease the hepatic lodgement of intraportally injected tumour cells. The present studies show that treatment with ketanserin also reduces the lodgement of i.v.-injected tumour cells in the lungs in both normal and traumatized rats.

Topics: Animals; Femoral Fractures; Fibrosarcoma; Ketanserin; Lung Neoplasms; Neoplasm Transplantation; Neoplastic Cells, Circulating; Piperidines; Rats; Sarcoma, Experimental; Serotonin Antagonists