Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effects of different subcutaneous doses of fentanyl (0.02, 0.04, 0.08, and 0.16 mg/kg), piritramide (0.63, 2.50, 10.0 and 40.0 mg/kg), and morphine (2.50, 5.00, 10.0 and 20.0 mg/kg) on self-stimulation in rats were studied. Different stimulus parameter combinations (SPC) inducing low, high or intermediate control response rates (CRR) were applied during the same experimental sessions. The three narcotic analgesics induced response depression (RD) and response stimulation (RS). RS was mostly observed at low dose levels; RD was dose-related. SPC's inducing low CRR were more sensitive than those inducing high CRR. Fentanyl was more potent than piritramide and than morphine. The RD is related to motor incapacitation, as the doses needed to effectively reduce self-stimulation also induced obvious catatonia. The RS probably is a more specific effect reflecting sensitization of structures involved in reinforcement of behavior.
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PMID:Intracranial self-stimulation in rats as a function of various stimulus parameters. VI. Influence of fentanyl, piritramide, and morphine on medial forebrain bundle stimulation with monopolar electrodes. 0 96

Fentanyl was used in 100 abdominal surgical interventions, combined with droperidol or with diazepan, always with good results as far as analgesia was concerned. Tensional variations that occurred during the induction were quite small and disappeared during the filling up. In the course of the intervention, tensional variations were only met with subjects suffering from high blood pressure. The respiratory depression that went with analgesia did not constitute an obstacle but made it necessary to use artificial ventilation for the intervetion. The awakening was always quick, smooth, without any vomiting and was influenced neither by the time taken up by the intervention nor by the condition of the patient. No residual respiratory depression requiring the use of an anti-morphinic was noted. At the end of the study, fentanyl appears as a powerful analgesic, easy to use and successful in all the cases of abdominal surgery. Its effect does not last, a drawback that can be avoided by the use of an intravenous drip.
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PMID:[Value of moderate fentanyl dosage during anesthesis in abdominal surgery. Apropos of 100 cases]. 0 82

The study of the effect of analgesics in the newborn is difficult in the clinical situation and resort must be made to animals. Pethidine given within 1 hour of delivery is believed to cause less depression than when the time interval is longer. This study investigates whether it is pethidine or its metabolites which cause respiratory depression by comparing the respiratory effects of pethidine and its metabolites in the newborn rabbit. Fentanyl and buphrenorphine were also investigated as alternative analgesics. The response in the newborn rabbit to anoxia, is periods of dyspnoea, primary apnoea, and gasping. The metabolites of pethidine increased the primary apnoea signifying depression almost as much as pethidine. Depression was also produced when anoxia was induced 5 minutes after pethidine. Fentanyl caused less depression than pethidine or its metabolites excepting normeperidinic acid. Buphrenorphine administration resulted in the least depression with little difference between the low and high doses. Thus both pethidine and its metabolites are factors in the persisting depression, while buphrenorphine compared well with pethidine and fentanyl.
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PMID:The role of analgesics in respiratory depression: a rabbit model. 1 6

Morphine, the principal alkaloid of "papaver somniferum" is the reference substance of central analgesics, the parmacodynamic constants of which are: analgesia and the possibility of addiction. Respiratory depression is, for many of them, a grave side-effect. At the present time, no substance in this category is fully satisfactory and all may result in dependence. Equi-analgesic doses of dextromoramide, phenoperidine and Fentanyl are less than those of morphine, whilst those of pethidine and pentazocine are higher. Study of the pharmacokinetics of these various substances indicates no common elements, and it is difficult to consider that the analgesic action is proportional to blood levels. Clinical assessment of the mean duration of action makes it possible to divide morphine derivatives into substances with a very short action (20 to 45 minutes) such as Febtanyl and phenoperidine, and those with a longer action (1 to 4 hours) which includes the majority of the other substances. The analgesic activity of Methoadone lasts for 4 to 6 hours. Morphine antagonists such as Methadone, nalophine, naloxone and naltrexone possess specific problems in terms of their utilization. Pharmacological data concerning theses substances are described.
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PMID:[Pharmacology of morphine and its derivatives (review)]. 2 28

In anaesthesiology of today, due to the increased use of strong analgetics, it is necessary to have an effective antagonist for mini- mizing the danger of respiratory depression in postoperative period. Naloxone, ( Narcan , R-Endo Laboratories Inc., Subsidiary of E. J. du Pont de Nemours and Co., (Inc.), USA), a new narcotic antagonist was investigated in this study. It has been applied to 58 patients in cases of respiratory depression at the end of anaesthesia in which fentanyl was given, (these cases constituted 14% of all anaesthesias). Fentanyl was given intravenously in fractional doses, (fig 1), during NLA, and other general anaesthesias, for operation and diagnostic examination ( exeption of cardiosurgery), in children and adolescents from two month-to nineteen years of age, (tab. 1.). Naloxone was given intravenously, in fractional doses from 1 microgram to 5 micrograms/kg body weight. As a criterium of an antidepressive effect of Naloxone--in addition to clinical evaluation, blood gases analyses and continuous capnographic recording has been accepted. In all 58 cases diminition of respiratory depression was observed 2-3 min. after injected each dose of Naloxone. Respiratory rate increased from 15 to 22/min. concentration of CO2 in expired gases decreased from 5-6% to 4,5%, (fig. 2 and 3), and regain of consciousness, and return of intensive reaction to endotracheal tube stimulation was observed. Naloxone produced neither changes in the cardiovascular system, nor side effects. Based on these results Naloxone has been suggested as an effective narcotic antagonist. It increase of the possibility of applying strong analgetics in children--allowing to keep a steady level of anaesthesia with easy elimination respiratory depression in the desired period of time.
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PMID:[Naloxone as a drug for improving anesthesia results in children]. 26 40

Total I.V. anesthesia was given to 20 patients using an Etomidate continuous infusion to maintain sleep, combined to Fentanyl analgesia, Droperidol, Pancuronium for muscular relaxation and artificial ventilation with an oxygen-air mixture. All these patients were carefully observed during and for several hours after the anesthesia and the results noted. With the Fentanyl dosages used in this technique, peroperative analgesia was frequently insufficient. More Fentanyl would probably be needed with the inherent dangers of prolonged postoperative depression.
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PMID:Total I.V. anesthesia using a continuous etomidate infusion. 54 55

The cardiovascular effects of three doses of intravenous fentanyl (50, 100, and 200 microgram) were determined in 42 adult patients undergoing intraabdominal surgical procedures with enflurane (2--3%) and nitrous oxide (50%) in oxygen. Fentanyl was administered a minimum of 40 minutes after induction of anesthesia and 30 minutes after initiation of the surgical procedure. Stroke volume, heart rate, cardiac output, mean arterial and central venous blood pressures, and peripheral arterial resistance were determined by computer analysis of the central aortic pulse-pressure curve according to the method of Warner. Measurements were made before and 2, 4, 6, 8, and 10 minutes after fentanyl. Fentanyl (50 microgram) produced increases in stroke volume and cardiac output as well as a decrease in peripheral arterial resistance but did not alter heart rate or mean arterial blood pressure. Fentanyl (100 microgram) did not significantly change any variable at any time. Fentanyl (1l (200 microgram) produced sustained decreases in stroke volume, cardiac output and mean arterial blood pressure and increased central venous pressure but did not alter heart rate or peripheral arterial resistance. The data indicate that fentanyl (50--100 microgram) stimulates or has no effect on cardiovascular dynamics during enflurane-nitrous oxide anesthesia but fentanyl (200 microgram) produces significant cardiovascular depression. Our findings suggest that small doses of intravenous fentanyl may be of benefit during enflurane-nitrous oxide but larger doses should probably be avoided.
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PMID:Cardiovascular effects of fentanyl during enflurane anesthesia in man. 57 55

Fentanyl is often used as an anesthetic supplement for short procedures because it has a rapid onset and brief duration of action. However, persistence of ventilatory depression several hours following the last dose has been seen. The authors studied the pharmacokinetics of fentanyl in the dog to find an explanation for the occasionally prolonged duration of action. 3H-fentanyl citrate, 10 or 100 microgram/kg, was injected intravenously in dogs anesthetized with enflurane-O2. Arterial plasma and urine were analyzed for unchanged 3H-fentanyl and for total 3H radioactivity. Kinetic indices were derived by nonlinear least-squares analysis of log concentration (ng/ml) vs. time relationships. Initially, the elimination of fentanyl from plasma was very rapid, and 98 per cent of the amount administered was removed from plasma in the first 5 min after an intravenous injection. However, the terminal elimination phase was prolonged (t1/2 = 199 +/- 17 min). The apparent volume of distribution was large (9.81/kg) and independent of dose. Repetitive doses produced an accumulation of fentanyl. 3H-labelled metabolites of fentanyl were present in the earliest samples of plasma, and accounted for the major portion of the total 3H radioactivity in both plasma and urine. Urine collected for six hours contained 36 per cent of the total 3H radioactivity administered, but only 4 per cent of fentanyl administered was excreted as unchanged fentanyl. The authors conclude that most of a single dose of fentanyl is rapidly eliminated from the body by biotransformation and leads to accumulation of the drug when administered in very large or repeated doses. Under these circumstances the slow release of drug from tissues results in persistent plasma levels of fentanyl and a prolonged duration of action.
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PMID:Pharmacokinetics of 3H-fentanyl in the dog anesthetized with enflurane. 76 May 97

Fentanyl was replaced by R 30730/Janssen (Fentatienyl) for neurolept analgesia (with intubation) of 34 persons who had ophthalmic surgery on account of detachment of the retina. The effects of the drug on the size of the pupils, blood pressure, heart rate and respiration were observed; also the duration of analgesia and the incidence of nausea and vomiting. There was a very slight negative effect on the size of the pupil, similar to that seen with halothane; systolic blood pressure fell by an average of 20%; the duration of analgesia and the degree of respiratory depression varied considerably. 12 of the 35 patients suffered from marked nausea and vomiting after the operation.
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PMID:[Clinical experience with r30730/Janssen in anaesthesia for ophthalmic surgery (author's transl)]. 91 72

The effect of microelectrophoretically and systemically applied opiates on neuronal discharge activity in the sensorimotor cortex of naive and morphine tolerant/dependent rats has been studied. In naive rats depression of spontaneous discharge activity was the predominant effect of low doses of phoretically applied morphine. Higher doses and repeated application frequently converted this effect into excitation. Only the depressant effect was antagonised by naloxone. Naloxone itself had no effect on spontaneous discharge activity when applied at dose-levels sufficient to antagonise the depressant effect of morphine. Levorphanol mimicked the action of morphine whereas dextrorphan was inactive. Morphine depressed the excitatory action of L-glutamate and of acetylcholine by a naloxone-antagonisable mechanism. Systemic application of Fentanyl mimicked the inhibitory effect of phoretically applied morphine upon transcallosally evoked discharge activity. The late response was markedly depressed whereas the primary response was little affected. Phoretically applied naloxone antagonised the effects of systemically applied Fentanyl. In chronically morphinised rats the depressant effect of microelectrophoretically administered morphine was almost lacking and a naloxone-resistant excitation became the predominant effect. In these animals the excitant effect of naloxone was also increased and the anti-glutamate effect and the anti-acetylcholine effect of morphine was abolished. The present data speak in favour of a postsynaptically located stereospecific receptor which mediates the inhibitory effects of opiates and which may be involved in the development of acute and chronic tolerance to these drugs.
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PMID:Actions of opiates upon single unit activity in the cortex of naive and tolerant rats. 98 31


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