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 143
- Downloads 0
Immobility stress induces depression-like behavior in the forced swim test in mice: effect of magnesium and imipramine.
Previously, we demonstrated antidepressant-like effect of magnesium (Mg) in the forced swim test (FST). Moreover, the joint administration of Mg and imipramine (IMI) at ineffective doses per se, resulted in a potent redu...
New neostigmine-based behavioral mouse model of abdominal pain.
Background: Animal models of visceral pain have gained much attention as an important tool to elucidate the possible mechanisms underlying functional gastrointestinal (GI) disorders. Here we report the development of a n...
Enhanced oxidative stress in hypertrophic cardiomyopathy.
Elevated plasma levels of inflammation and endothelial dysfunction markers have been reported in patients with hypertrophic cardiomyopathy (HCM). The aim of the current study was to determine whether HCM is associated wi...
Tolerance liability of diazepam is dependent on the dose used for protracted treatment.
Background: Behavioral effects of benzodiazepines following repeated exposure vary according to the intrinsic efficacy of the benzodiazepine studied, treatment schedule and the behavioral parameters evaluated. Methods: W...
Acute treatment with metformin improves cardiac function following isoproterenol induced myocardial infarction in rats.
It has been proposed that metformin exerts protective effects on ischemic hearts. In the present study, we evaluated the effects of metformin on cardiac function, hemodynamic parameters, and histopathological changes in...