The antinociceptive and ventilatory effects of morphine and other opioid agonists were determined in three rhesus monkeys during a period of morphine maintenance, as well as before and after the chronic exposure to morphine. Before the onset of the daily dosing regimen, morphine increased tail-withdrawal latencies from 50 degrees C water, with an ED50 of 6.4 +/- 2.1 mg/kg. Daily injection of 3....

STUDY OBJECTIVE To assess concentrations of morphine and its metabolites after patient-controlled analgesia (PCA). DESIGN Pilot pharmacokinetic study of morphine and pharmacokinetic simulation. SETTING Post-anesthesia care room and ward of an academic teaching hospital. PATIENTS 10 ASA physical status I, II, and III postoperative surgical patients. INTERVENTIONS Patients received morphi...

this research was designed to study sexual differences in place conditioning induced by morphine in offspring born of female wistar rats mated with drug-naïve males. mothers were exposed to morphine during the 14th-16th days of gestational. control dams were simply saline-injected. female and male virgin offspring born of morphine-treated or saline-treated mothers were separately housed until b...

Morphine-3- and morphine-6-glucuronide are morphine's major metabolites. As morphine-6-glucuronide produces stronger analgesia than morphine, we investigated the effects of acute and chronic morphine glucuronides on adenylyl cyclase (AC) activity. Using COS-7 cells cotransfected with representatives of the nine cloned AC isozymes, we show that AC-I and V are inhibited by acute morphine and morp...

BACKGROUND Opiates affect blood factors as well as pain and inflammation in a gender-dependent manner. The aim of the present study was to evaluate the effects of morphine on serum glucose, cholesterol, triglycerides, and urea in gonadectomized and inflammation conditions. METHODS Animals were divided as follows: control group, carrageenan and chronic morphine recipients, acute morphine recip...

We have previously shown that the naturally occurring levo-morphine at a subanalgesic picomolar dose pretreated i.t. induces antianalgesia against levo-morphine-produced antinociception. We now report that the synthetic stereo-enantiomer dextro-morphine, even at an extremely low femtomolar dose, induces antianalgesia against levo-morphine-produced antinociception using the tail-flick (TF) test ...

Morphine is an opioid analgesic drug commonly used for pain relief in cancer patients. Here, we report that morphine enhances the mammosphere forming capacity and increases the expression of stemness-related transcription factors Oct4, Sox2 and Nanog. Treatment with morphine leads to enrichment of a side population fraction in MCF-7 cells and the CD44+/CD24(-/low) population in BT549 cells. Con...

OBJECTIVES To evaluate the effects of intrathecal morphine on pulmonary function, analgesia, and morphine plasma concentrations after cardiac surgery. INTRODUCTION Lung dysfunction increases morbidity and mortality after cardiac surgery. Regional analgesia may improve pulmonary outcomes by reducing pain, but the occurrence of this benefit remains controversial. METHODS Forty-two patients we...

BACKGROUND The feasibility of drug monitoring of serum concentrations of morphine, morphine-6-glucuronide (M6G) and morphine-3-glucuronide (M3G) during chronic morphine therapy is not established. One important factor relevant to drug monitoring is to what extent morphine, M6G and M3G serum concentrations fluctuate during stable morphine treatment. METHODS We included twenty-nine patients adm...

As a follow-up study to an earlier report that racemic fenfluramine can acutely potentiate the analgesic effects of morphine in humans, we investigated the effects of fenfluramine on the development of tolerance to morphine analgesia in rats. Antinociceptive effect, as measured by the tail-flick latency, was studied over 8 days in rats that received continuous i.v. infusion of 1) 22 mg/kg/day o...