Pharmacological preconditioning of the brain: a possible interplay between opioid and calcitonin gene related peptide transduction systems.
Journal Title: Pharmacological Reports - Year 2008, Vol 60, Issue 6
Abstract
The present study has been undertaken to investigate the possible link between calcitonin gene related peptide (CGRP) and opioid receptor transduction systems in the neuroprotective mechanism of pharmacological preconditioning. Occlusion of the bilateral carotid artery for 17 min, followed by reperfusion for 24 h, was employed to produce ischemia and reperfusion (I/R) induced cerebral injury in mice. Cerebral infarct size was measured by using triphenyltetrazolium chloride staining. Memory was assessed using the Morris water maze (MWM) test. Degree of motor incoordination was evaluated using the inclined beam walk test, rota-rod test, and lateral push test. Morphine (8 mg/kg, ip), an opioid agonist, and capsaicin (0.1 mg/kg, iv), a CGRP releasing agent, were administered 24 h before surgery to separate groups of animals to induce pharmacological preconditioning. Bilateral carotid artery occlusion, followed by reperfusion, produced a significant increase in the cerebral infarct size and impaired memory as well as motor coordination. Morphine and capsaicin treatment produced both a significant decrease in the cerebral infarct size and a reversal of I/R-induced impairment of memory and motor-coordination. Morphine-induced (8 mg/kg, ip) neuroprotective effects were completely decreased by sumatriptan (8 mg/kg, ip, a CGRPrelease inhibitor) administered 1 h before and 6 h and 12 h after morphine administration. Capsaicin-induced neuroprotection was decreased by naloxone (5 mg/kg, ip, an opioid antagonist) administered 1 h before and 6 h and 12 h after capsaicin administration. These findings indicate that the transduction systems mediating morphine- and capsaicin-induced pharmacological preconditioning in brain are possibly interlinked with one another.
Authors and Affiliations
Ashish Rehni, Thakur Singh, Amteshwar Jaggi, Nirmal Sing
Assessing circadian rhythms during prolonged midazolam infusion in the pediatric intensive care unit (PICU) children.
Background: This study evaluates possible circadian rhythms during prolonged midazolam infusion in 27 pediatric intensive care unit (PICU) children under mechanical ventilation. Methods: Blood samples for midazolam and 1...
Cytochrome P450-dependent metabolism of omega-6 and omega-3 long-chain polyunsaturated fatty acids.
Dietary fish oil omega-3 fatty acids (n-3 PUFAs), such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), protect against arrhythmia and sudden cardiac death using largely unknown mechanisms. EPA and DHA may...
Interaction between tobacco smoke and alcohol in animal models.
This study aimed to evaluate the impact of nicotine and other xenobiotics contained in tobacco smoke on the pharmacokinetics of ethyl alcohol and on the levels of toxic ethanol metabolites such as acetic aldehyde.We also...
Cigarette smoke-induced biochemical perturbations in human erythrocytes and attenuation by epigallocatechin-3-gallate--tea catechin.
The protective effect of epigallocatechin-3-gallate (EGCG) against cigarette smoke (CS) induced alterations in human erythrocyte was studied using an in vitro model. Hemolysis, carboxyhemoglobin, osmotic fragility, hemin...
Raloxifene similarly affects the skeletal system of male and ovariectomized female rats.
Raloxifene, a selective estrogen receptor modulator, is used for prevention and treatment of osteoporosis in postmenopausal women. Raloxifene use in male subjects is increasingly considered and a few clinical studies of...