Search results for "Morphine"
showing 10 items of 145 documents
Ankk1 Loss of Function Disrupts Dopaminergic Pathways in Zebrafish
2022
Ankyrin repeat and kinase domain containing 1 (ANKK1) is a member of the receptor-interacting protein serine/threonine kinase family, known to be involved in cell proliferation, differentiation and activation of transcription factors. Genetic variation within the ANKK1 locus is suggested to play a role in vulnerability to addictions. However, ANKK1 mechanism of action is still poorly understood. It has been suggested that ANKK1 may affect the development and/or functioning of dopaminergic pathways. To test this hypothesis, we generated a CRISPR-Cas9 loss of function ankk1 zebrafish line causing a 27 bp insertion that disrupts the ankk1 sequence introducing an early stop codon. We found that…
Real-time Patterns of Behavior Following Nociceptive Stimulation in Rats
2016
The hot-plate test is employed, in rodents, to assess the analgesic properties of drugs. The surface where the animal is placed is normally maintained at a constant temperature around 50°C or 55°C. For this reason rat’s behavior, once placed on the heated surface, can be observed only for few seconds, and a necessary interruption occurs following an a priori-established cut-off to avoid tissue injuries. Such a narrow time window dampened the assessment of fine behavioral characteristics such as the temporal structure of behavior. In the present paper we demonstrate the possibility to apply a refined multivariate approach, known as T-pattern analysis (TPA), to describe the temporal character…
Analgesic Effect of Intravenous Ketamine in Cancer Patients on Morphine Therapy
2000
Pain not responsive to morphine is often problematic. Animal and clinical studies have suggested that N-methyl-D-aspartate (NMDA) antagonists, such as ketamine, may be effective in improving opioid analgesia in difficult pain syndromes, such as neuropathic pain. A slow bolus of subhypnotic doses of ketamine (0.25 mg/kg or 0.50 mg/kg) was given to 10 cancer patients whose pain was unrelieved by morphine in a randomized, double-blind, crossover, double-dose study. Pain intensity on a 0 to 10 numerical scale; nausea and vomiting, drowsiness, confusion, and dry mouth, using a scale from 0 to 3 (not at all, slight, a lot, awful); Mini-Mental State Examination (MMSE) (0-30); and arterial pressure…
Effects of Caffeine as an Adjuvant to Morphine in Advanced Cancer Patients
2001
Psychomotor abnormalities are one of the complications of opioid therapy in advanced cancer patients. Caffeine has potential properties to counteract the central effects of morphine. Twelve patients receiving stable doses of slow release morphine with adequate pain relief were scheduled for this double-blind placebo-controlled crossover trial. The treatment consisted of an intravenous dose of 1/6 of the daily morphine dose, using an intravenous/oral conversion ratio of 1:3. The dose calculated was administered in 5 minutes. Patients were randomly divided to received in a double-blind manner an infusion of 200 mg of caffeine or saline solution intravenously over one hour. A crossover took pl…
World Health Organization guidelines for cancer pain: a reappraisal
2005
Pain is a prevalent symptom experienced by at least 30% ofpatients undergoing an oncological treatment for metastaticdisease and by more than 70% of advanced cancer patients[1]. In 1986 the World Health Organization [2] published a setof guidelines for cancer pain management based on the three-step analgesic ladder [2]. The main aim of WHO guidelienswas to legitimize the prescribing of strong opioids, arisingfrom evidence of poor management of cancer pain, due toreluctance of health care professionals, institutions, and gov-ernment to use opioids because of fears of addition, toleranceand illegal abuse.Its application is reported to achieve satisfactory pain reliefin up to 90% of patients w…
Different mechanism of relaxation induced by aporphine alkaloids in rat uterus.
1993
Abstract We have examined the uterine relaxant action of three aporphine molecules (S-glaucine, S-boldine and R-apomorphine) in two experimental conditions, with and without calcium in the bathing solution, and compared these effects with those obtained with the calcium antagonists verapamil and diltiazem. The present study shows that the alkaloids relax the uterine muscle but with different mechanisms of action. In Ca2+-containing solution all three alkaloids relaxed the uterus previously contracted by KCl or acetylcholine, but in Ca2+-free medium only R-apomorphine was able to relax oxytocin-induced contraction. The calcium antagonists, verapamil and diltiazem, relaxed KCl- or acetylcholi…
Combined epidural morphine and bupivacaine in the treatment of lumbosacral radicular neuropathic pain: a noncontrolled prospective study
2016
Simone Vigneri,1,2 Gianfranco Sindaco,2 Marco La Grua,2 Matteo Zanella,2 Laura Ravaioli,2 Valentina Paci,2 Gilberto Pari2 1Department of Experimental Biomedicine and Clinical Neurosciences, University of Palermo, Palermo, 2Advanced Algology Research and Pain Medicine Unit, Santa Maria Maddalena Hospital, Occhiobello, RO, Italy Objective: The aim of this study was to investigate the therapeutic effectiveness of epidural morphine and bupivacaine in patients with chronic lumbosacral radicular neuropathic pain after the cessation of treatment.Methods: Twenty-two patients with chronic lumbosacral pain with neuropathic features were enrolled. An indwelling catheter was placed into the epidural sp…
Failure of opioids to affect excitation and contraction in isolated ventricular heart muscle
1989
The opioid agonists morphine (selective for mu-receptors) and ethylketocyclazocine (selective for kappa-receptors), at concentrations evoking strong effects in neuronal structures, did not significantly affect the configuration of the intracellularly recorded action potential and the force of contraction in ventricular heart muscle isolated from guinea pigs, rabbits and man. These results suggest that any changes of heart functions in vivo in response to opioid-like drugs are probably not mediated postsynaptically at the myocardial cell membrane but rather presynaptically, influencing the release of noradrenaline and/or acetylcholine from the nerve terminals.
The role of tapentadol as a strong opioid in cancer pain management: a systematic and critical review
2017
The aim of this review was to assess the role of tapentadol given at medium-high doses in opioid-tolerant patients for cancer pain management in place of step-3 analgesics.A systematic literature search was performed out of which six studies and one secondary analysis provided data regarding tapentadol used as a step-3 analgesic for this review. Tapentadol, when used at ≥60 mg of oral morphine equivalents in opioid-tolerant patients with cancer pain, or passing from step-2 doses to ≥60 mg of oral morphine equivalents, was well tolerated and effective and could be considered as a flexible drug to be used for the management of moderate-to-severe cancer pain. The limited occurrence of gastroin…
Lack of autoreceptor mediated regulation of the spontaneous dopamine turnover in the isolated neurointermediate lobe of the rat pituitary gland in vi…
1990
Isolated neurointermediate lobes of the rat pituitary gland were incubated in Krebs-HEPES solution and the spontaneous outflow of endogenous dopamine and its metabolites (DOPAC, HVA and MOPET) was determined by HPLC with electrochemical detection. The spontaneous outflow of dopamine metabolites (about 1500 fmol/10 min) largely exceeded that of dopamine (about 60 fmol/10 min). Apomorphine concentration-dependently (IC50, 205 nmol/l) reduced the spontaneous outflow of the dopamine metabolites. The effect of apomorphine developed slowly and was progressive over an observation period of 70 min. After 1 h of exposure to a maximall effective concentration of apomorphine (10 mumol/l), the outflow …