Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0030193 (pain)
 261,466 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Naloxone was used in 20 patients divided into two series: series A consisted of 10 adults with an average age of 50.6 years (+/- 12.03) and series B 10 children with an average age of 8.5 years (+/- 5.16). Naloxone was given in the treatment of postoperative respiratory depression related to persistence of morphine impregnation, the patients having received either fentanyl (mean dose 0.04 mg/kg/h) or dextromoramide (mean dose 1.15 mg/kg/h). The mean dose of naloxone was 0.26 mg +/- 0.10, i.e. 3.9 microgram/kg in series A, and 0.13 mg +/- 0.11, i.e. 5.3 microgram/kg in series B. In both series, study of ventilatory function showed correction and stabilisation of the various parameters (F/min, Vt and V) up to 180 minutes after the injection. Recovery was rapid in both groups (7 to 10 min) and of good quality. Whilst it was accompanied in a number of cases by the recurrence of pain, the latter never required specific relief. The administration of naloxone was associated with an increase in heart rate (non-significant) at 10 min in series A and 30 min in series B. Apart an episode of nausea in one case of series A, no disagreeable side effects were observed.
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PMID:[The use of naloxone in neuroleptoanalgesia]. 2 36

The effect of naloxone on dental postoperative pain was studied to examine the hypothesis that endorphins mediate placebo analgesia. All patients had extraction of impacted mandibular third molars with diazepam, N2O, and local block with mepivacaine. 3 h and 4 h after surgery naloxone or a placebo was given under randomised, double-blind conditions. Pain was evaluated on a visual analogue scale. Patients given naloxone reported significantly greater pain than those given placebo. Patients given placebo as their first drug was either placebo responders, whose pain was reduced or unchanged, or nonresponders whose pain increased. Naloxone given as a second drug produced no additional increase in pain levels in nonresponders but did increase pain levels of placebo responders. Nonresponders had a final mean pain rating identical to that of responders who received naloxone as their second drug. Thus the enhancement of reported pain produced by naloxone can be entirely accounted for by its effect on placebo responders. These data are consistent with the hypothesis that endorphin release mediates placebo analgesia for dental postoperative pain.
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PMID:The mechanism of placebo analgesia. 8 May 79

Electrophysiological studies of the nociceptive reflex (R3) were carried out in eight normal subjects, and one patient with congenital insensitivity to pain, in order to compare the effects of naloxone and a placebo. No significant variation in the reflex threshold was seen in the normal subjects. Two electrophysiological abnormalities were observed in the patient: a 350 per cent spontaneous elevation in the R3 threshold compared to the control group; a rapid and large drop (67 per cent) in the threshold lasting for about ten minutes after the injection of Naloxone. These results suggest that in this particular case the insensitivity to pain could be related to the permanent hyperactivity of a morphine-like inhibitory system.
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PMID:[Insensitivity to pain: electrophysiological study of the nociceptive reflex. Influence of naloxone (author's transl)]. 8 87

Clonidine is able to increase the threshold for vocalisation during stimulation and the threshold for vocalisation after withdrawal of stimulus (vocalisation afterdischarge). These effects of clonidine were investigated after treatment of rats with drugs influencing central monoaminergic and cholinergic mechanisms. Chlorpromazine, atropine and p-chlorophenylalanine increased the activity of clonidine at both thresholds while phenoxybenzamine and reserpine pretreatment increased the activity at the thresholds for vocalisation only. Yohimbine decreased clonidine activity at both thresholds while 5-HTP and alpha-methyl-p-tyrosine decreased the effects at the threshold for vocalisation afterdischarge. Naloxone did not change the activity of clonidine at either pain response studied. It is concluded from the present findings that influence from several neuronal systems modulate the antinociceptive action of clonidine. The inhibition of the medullary nociceptive response after clonidine might be connected to a decreased activity of noradrenergic neurons. Endogenous noradrenaline seems to be of minor importance in mediating this effect. It is moreover shown that decreased cholinergic receptor activity enhances clonidine antinociceptive action on both medullary and diencephalic-rhinencephalic pain responses. The possible involvement of serotonin these functional responses after clonidine is also discussed.
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PMID:Clonidine antinociceptive activity: effects of drugs influencing central monoaminergic and cholinergic mechanisms in the rat. 13 92

Narcotic analgesics and related drugs act as agonists on several receptors that are responsible for their effects on pain perception, mood and feeling state, and respiration, as well as other pharmacologic actions. Naloxone is the first discovered antagonist that is devoid of agonistic activity and appears to be a competitive antagonist at several receptors. The ability of naloxone to displace or prevent the binding of agonistic narcotics is partly responsible for its antagonistic effects. The ability of naloxone to rectify narcotic-depressed homeostats and precipitate abstinence is also related to its antagonistic activity. Certain cautions and principles apply in the use of naloxone in treating narcotic overdose, reversing surgical analgesia, and the treatment of neonates and children. Unapproved uses of naloxine include reversing the psychotomimetic effects of certain agonists-antagonists, terminating narcotic-induced convulsions and coma, reversing non-narcotic depression, diagnosing physical dependence, and treating narcotic addicts.
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PMID:Naloxone. 18 95

Blockade of opiate receptors by naloxone (2 mg/kg) was found to produce a significant increase in pain sensitivity as measured by the tail-flick test. This finding supports the view that endogenous opiate systems may play a role in the modulation of pain sensitivity. Naloxone, however, was found to have no effect on pain responsiveness as measured by tail-pinch. These findings, together with additional reports, suggest that endogenous opiate systems may exert differential actions on different sensory modalities.
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PMID:Effect of opiate receptor blockade on pain sensitivity in the rat. 19 77

Extra- and intracellular recordings were obtained from physiologically identified, spinal neurones in the 6th and 7th lumbar segments of the pentobarbitone-anaesthetized cat. Microiontophoretically applied methionine- and leucine-enkephalin reversibly inhibited the spontaneous, synaptically induced, and L-glutamate-induced activity in the majority of dorsal horn neurones studied in laminae 4, 5 and 6 of Rexed. Most of these depressant effects were antagonized by the prior microiontophoretic application of the opiate antagonist naloxone. Intracellular studies performed on dorsal horn neurones and motoneurones revealed that microiontophoretically applied methionine- and leucine-enkephalin caused no change in the resting membrane potential or the membrane resistance. Neither spike initiation nor spike overshoot were detectably altered by either enkephalin. The membrane depolarization and associated decrease in membrane resistance following microiontophoretic L-glutamate application were effectively blocked by the prior application of enkephalin. Naloxone, which by itself had no detectable effect on the membrane resistance, antagonized this effect. We propose that [enkephalinergic] cells in lamina II and III may modulate cells subserving somatosensory perception, including pain.
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PMID:The effects of methionine- and leucine-enkephalin on spinal neurones of the cat. 22 94

Hibernation reduces substantially the heart rate of hamsters as well as the respiratory rate, the body temperature and the arousal level. The heart rate is reversed dramatically by the injection of low doses of Naloxone and in some cases the hamster arouses prematurely from hibernation. The effect is not due to the pain of the injection because saline injections do not produce such changes. The effect requires a pre-existing state of hibernation because Naloxone has no cardioacceleratory or arousal effect in non-hibernating hamsters that have had their heart rate and body temperature decreased substantially during hypothermia. These results suggest that endogenous opioids may contribute specifically to the state of hibernation. Moreover, a physiological role may exist for an anti-opioid system in the promotion of arousal from hibernation.
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PMID:Hibernation: an opioid-dependent state? 23 Aug 86

Recently, Mayer (1977) and Adams (1976) proved that both acupuncture and direct electrostimulation of deep encephalic structures produce an analgesic effect releasing a neurotransmitter similar to morphine (endorphine). We have verified this hypothesis, using the transcutaneous electrotherapy in five patients with chronic pain at the back (postherpetic neuralgia in 3, pain cancer in 2). All patients related a certain analgesic effect during electrotherapy, with a reduction in pain of more than 50 per cent. During electroanalgesia we administered Naloxone (an antagonist of morphine). In 3 cases we observed a clear, although short, return of algic symptomatology. At the contrary, in other two patients Naloxone caused briefly a further and clear reduction in the pain.
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PMID:[Transcutaneous electroanalgesia and naloxone. Clinical aspects (author's transl)]. 31 30

The hypothesis that painful stimuli activate the endogenous opioid (endorphin) system in humans was tested by examining the effect of the opiate antagonist naloxone on experimentally induced ischemic pain and on subjective mood ratings. Intravenous injections of saline or naloxone hydrochloride (2 and 10 mg) were administered under double-blind conditions to 12 subjects. Naloxone did not affect the pain ratings. However, a significant dose-related effect of naloxone on tension-anxiety was found, suggesting that the endorphins. like exogenously administered opiates, may have antianxiety properties.
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PMID:Effects of naloxone on experimentally induced ischemic pain and on mood in human subjects. 32 52


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