Antinociception after intrathecal biphalin application in rats: a reevaluation and novel, rapid method to confirm correct catheter tip position.
Journal Title: Pharmacological Reports - Year 2005, Vol 57, Issue 4
Abstract
The opioid peptide dimmer biphalin [(Tyr-D-Ala-Gly-Phe-NH-)(2)] has high potency both in vivo and in vitro. Its antinociceptive activity depends on the route of administration: the lowest potency is after subcutaneous, and the highest after intrathecal or inracerebroventricular administration. We tested the analgesic activity of biphalin in a wide range of doses after intrathecal administration to rats. Doses as low as 0.005 nmol produced significant analgesia. Increasing the dose up to 2 nmol elevated and prolonged antinociception without any evident side effects, indicating that biphalin is an extremely potent opioid after intrathecal application with a wide therapeutic window. The highest dose tested (20 nmol) produced full analgesia and body rigidity lasting 2-3 h. After muscle tone returned to normal, antinociception lasted for several more hours. During these studies we observed a correlation between responses to biphalin and catheter placement. Postmortem verification of catheter placement revealed that in those rats in which high-dose biphalin did not produce analgesia or muscle rigidity, the catheter was positioned incorrectly or the flow of drug solution was obstructed. Therefore, a secondary conclusion is that assessment of transient rigidity after administration of a high dose of biphalin may be used as an easy method to confirm intrathecal placement of the catheter.
Authors and Affiliations
Dariusz Kosson, Iwona Bonney, Daniel Carr, Ewa Mayzner-Zawadzka, Andrzej Lipkowski
Keywords
Related Articles
- EP ID EP96442
- DOI -
- Views 138
- Downloads 0
Effects of 3-aminopyridine-induced seizures on platelet eicosanoid synthesis.
We investigated the influence of recurrent epileptic seizures on the arachidonic acid (AA) cascade in platelets and brain microvessels, using [(14)C]AA as a tracer substrate and chromatographic determination. The recurre...
Inhibitory effect of antidepressants on B16F10 melanoma tumor growth.
Background: Antidepressant drugs, like fluoxetine, a selective serotonin reuptake inhibitor, desipramine, a nonselective noradrenaline reuptake inhibitor, and mirtazapine, an antagonist of noradrenaline α2 auto- and hete...
NADPH oxidase-derived reactive oxygen species in the regulation of endothelial phenotype.
Endothelial dysfunction comprising impairment of endothelium-dependent vasodilator function and increased endothelial activation contributes to the pathophysiology of cardiovascular diseases such as atherosclerosis, diab...
Inhibitors of phosphatidylinositide 3-kinase: effects on reactive oxygen species and platelet aggregation.
Phosphoinositide 3-kinase (PI 3-kinase) exists in cells as a family of isoforms. The enzymes are important regulators of fundamental metabolic processes, such as energy utilization, growth, cell proliferation and surviva...
Sphingosine-1-phosphate augments agonist-mediated contraction in the bronchial smooth muscles of mice.
The effects of sphingosine-1-phosphate (S1P) on bronchial smooth muscle (BSM) contractility were investigated in naive mice. S1P had no effect on the basal tone of the isolated BSM tissues. However, in the presence of S1...