We have shown previously that the administration of morphine (0.8 mg/kg) to patients with COPD increases the VO2max by 19.3 percent. A recent study demonstrated that the administration of low-dose nebulized morphine (approximately 2 mg) increased the endurance time of patients with severe lung disease by 1 min (35 percent) with few systemic side effects. This double-blind crossover study evalua...

In this study, we determined if changes in heart catecholamine content during naloxone-induced withdrawal correlated with modifications in heart rate. In addition, we determined plasma concentrations of corticosterone as an index of the hypothalamo-pituitary-adrenal (HPA) axis. The effects of naloxone on norepinephrine, epinephrine or dopamine content and turnover, plasma concentrations of cort...

Introduction: There are evidences showing the role of nitric oxide in the opiate reward properties. The role of nitric oxide signaling pathway as an intracellular mechanism on augmentation of long term potentiation in hippocampal CA1 area of rats is also confirmed. It has been also reported that oral morphine dependence facilitates formation of spatial learning and memory via activation of NMDA...

R.J. KATZ, A CTH~_l o antagonism of morphine-induced behavioral activation in the mouse, European J. Pharmacol. 53 (1979) 383--385. The 4-10 fragment of adrenocort icotrophic hormone (ACTH4_10; Met-Glu-His-Phe-Arg-Trp-Gly) was administered intracerebroventricularly to C57B1 mice with and without concurrent systemic injection of a standard dose of morphine sulfate. Morphine produced s tereotyped...

Tolerance to the analgesic effects of an opioid occurs after its chronic administration, a pharmacological phenomenon that has been associated with the development of abnormal pain sensitivity such as hyperalgesia. In the present study, we examined the role of spinal glutamate transporters (GTs) in the development of both morphine tolerance and associated thermal hyperalgesia. Chronic morphine ...

objective(s): morphine dependence (md) potently protects heart against ischemia reperfusion (ir) injury through specific signaling mechanisms, which are different from the pathways involved in acute morphine treatment or classical preconditioning. since opioid receptor density changes post cerebral ischemia strongly correlated with brain histological damage, in the present study, we tried to el...

Introduction: There are evidences showing the role of nitric oxide in the opiate reward properties. The role of nitric oxide signaling pathway as an intracellular mechanism on augmentation of long term potentiation in hippocampal CA1 area of rats is also confirmed. It has been also reported that oral morphine dependence facilitates formation of spatial learning and memory via activation of N...

Morphine inhibits small intestinal transit in mice, although few mu-opioid receptors are present in the ileum. The present study focused on the action of morphine in the isolated mouse ileum to reveal the mechanism by which morphine inhibits mouse small intestinal transit. In the isolated circular muscle, morphine caused tonic contraction. This contraction was potently inhibited by naloxone and...

BACKGROUND The efflux transporter P-glycoprotein, a member of the adenosine triphosphate-binding cassette superfamily, is a major determinant of the pharmacokinetics and pharmacodynamics of the opioid loperamide, a well-recognized antidiarrheal agent. Animal studies indicate that P-glycoprotein limits morphine entry into the brain. In this study, the authors examined whether other opioids of im...

we have previously evaluated the effect of nimodipine, l-type calcium channel blocker, on memory loss during spontaneous morphine withdrawal. in the present study the effect of nimodipine on memory loss in naloxone-induced morphine withdrawal mice was investigated. mice were made dependent by increasing doses of morphine for three days. object recognition task that was used for evaluation of me...