No abstract available.
Classification* ; Hallucinogens* ; Narcotics* ; Pharmacology*

The incidence of life-threatening anaphylactoid reactions during anesthesia has been increasing. Specific allergic reactions during anesthesia are usually due to muscle relaxants, barbiturates, local anesthetics, narcotics, radiocontrast media, antibiotics, and colloids. Thrombokinase, a hemostatic agent, has been used widely in clinical practice and severe anaphylactoid reactions to thrombokinase can occur rarely. We experienced two cases of anaphylactoid reactions after thrombokinase administration.
Anesthesia ; Anesthetics, Local ; Anti-Bacterial Agents ; Barbiturates ; Colloids ; Contrast Media ; Factor Xa* ; Hypersensitivity ; Incidence ; Narcotics ; Pharmacology

Adult ; Analgesics, Opioid ; pharmacology ; Female ; Fentanyl ; pharmacology ; Humans ; In Vitro Techniques ; Interleukin-6 ; blood ; Male ; Morphine ; pharmacology ; Narcotics ; pharmacology ; Tumor Necrosis Factor-alpha ; analysis

INTRODUCTIONThe aim of this study was to determine the prevalence and characteristics of benzodiazepine (BZD) abuse among intravenous opioid users in Singapore.

MATERIALS AND METHODSEligibility criteria for inclusion in this study were all intravenous buprenorphine abusers, who presented to the Community Addictions Management Programme (CAMP) over a 1-year period from February 2005 to January 2006. One hundred and twenty subjects, who consented to the study, completed an interviewer-administered questionnaire and underwent blood test for blood-borne viral infections.

RESULTSThe age of the 120 subjects ranged from 20 to 64 years, with a mean age of 39.0 (SD 8.0) years. The majority of the participants were male (90.0%); 48.3% were Chinese. Ninety-eight (81.7%) patients were using BZDs concomitantly. Midazolam was the most commonly used BZD. Buprenorphine abusers who were concomitantly using BZDs were significantly younger and reported an earlier age of onset of illicit drug abuse as compared to those not using BZDs. Those abusing BZDs were more likely to share syringes (x 2 = 5.8, P = 0.02), and were more likely to be seropositive for hepatitis C virus (x 2 = 4.3, P = 0.04).

CONCLUSIONSThis study highlights the extreme caution that needs to be exercised in prescribing BZDs to all patients in general and patients with injecting drug use or histories of drug abuse in particular. At a public health level, general practitioners (GPs) who prescribe buprenorphine should have compulsory training which highlights the potential dangers of abuse and concomitant abuse of BZDs.

Adult ; Buprenorphine ; pharmacology ; Female ; Humans ; Hypnotics and Sedatives ; pharmacology ; Male ; Midazolam ; pharmacology ; Middle Aged ; Narcotics ; pharmacology ; Prevalence ; Retrospective Studies ; Singapore ; epidemiology ; Substance-Related Disorders ; epidemiology

AIMTo determine whether testosterone is involved in morphine withdrawal syndrome (WS).

METHODSIn order to induce dependency, rats were treated with subcutaneous injection of morphine (days 1-2, 5 mg/kg; days 3-5, 7.5 mg/kg; days 6-8, 10 mg/kg), and after the last dose of morphine (day 8) WS was induced by intraperitoneal injection of naloxone (1 mg/kg). Wet dog shake (WDS), abdomen writhing (AW), and jumps (J) were recorded as indicators of WS.

RESULTSThe severity of WDS, AW, and J in male rats was greater than that in females. Accordingly, in 4-week castrated and flutamide-treated (10 mg/kg/day for 8 days, i.p.) male rats, WDS, AW, and J were significantly decreased compared to male control rats. Testosterone replacement therapy (10 mg/kg/day for 8 days, i.m.) in 4-week castrated rats restored the severity of WDS, AW, and J behaviors to the level of non-castrated male rats, whereas testosterone potentiated the WDS behavior in non-castrated male rats.

CONCLUSIONIt can be concluded that testosterone might be effectively involved in morphine WS.

Androgen Antagonists ; pharmacology ; Androgens ; pharmacology ; physiology ; Animals ; Behavior, Animal ; Female ; Flutamide ; pharmacology ; Male ; Morphine ; pharmacology ; Morphine Dependence ; physiopathology ; Naloxone ; pharmacology ; Narcotic Antagonists ; pharmacology ; Narcotics ; pharmacology ; Orchiectomy ; Rats ; Rats, Wistar ; Severity of Illness Index ; Substance Withdrawal Syndrome ; physiopathology ; Testosterone ; pharmacology ; physiology

BACKGROUND: It is emphasized that repetitive stimulation of small diameter afferent fibers produces a progressive increase in the action potential discharge and a prolonged increase in the excitability of neurons in the spinal cord following the stimulus and that this facilitatory component has a unique pharmacology. To investigate the behavioral parallels of this spinal facilitation, we evalusted the antinociceptive effects of intrathecal morphine, N-methyl-D-aspartate(NMDA), (+)-5-methyl-10,11- dihydro-5H-dibizo(a,d) cycloheptene-5, 10-imine hydrogen maleate(MK801) and (+/-)-3-(2-carboxy- piperazine-4-yl)-propyl-I-phosphonic acid(CPP), on the formalin test in rats. METHODS: Four to six days after chronic lumbar intrathecal catheterization, normal saline, morphine(0.1 to 30 ug), MK801(0.1 to 10 ug), CPP(0.1 to 5 ug) or NMDA(10 or 100 ng) were administered intrathecally before formalin injection. Spontanesous flinches were observed at 1-2 and 5-6 min(phase 1) and at 10 min intervals thereafter for 50 min(phase 2) after subcutaneous formalin injection into the dorsum of the right hind paw for each drug treated rats. RESULTS: Intrathecal morphine produced dose dependent inhibition of the phase 1 and phase 2 response(ED50=0.63 ug and 0.37 ug, respectively). Intrathecal MK801(0.1 to 10 ug) and CPP(0.1 to 5 ug) inhibited the phase 2 response more strongly than phase 1 response and inhibition of the phase 2 response(P<0.05 at any dose) was dose dependent(ED50=0.54 ug for MK801 and 0.15 ug for CPP). 1ntrathecal NMDA(10 or 100 ng) produced augmented responses in the intermediate and phase 2(P<0.05), but had no effect on the phase 1 response(P>0.7). Relative potencies of MK801 and CPP when compared with morphine were 1.34 and 0.41, respectively. CONCLUSIONS: This study suggests that intrathecal morphine and NMDA receptor antagonist(MK801 and CPP) have an antinociceptive effect on pathological pain mediated by central sensitization and that NMDA receptor antagonists can be utilized selectively in the treatment of components of central sensitization.
Action Potentials ; Analgesics ; Animals ; Catheterization ; Catheters ; Central Nervous System Sensitization ; Dizocilpine Maleate* ; Formaldehyde* ; Hydrogen ; Morphine* ; N-Methylaspartate* ; Narcotics ; Neurons ; Pain Measurement* ; Pharmacology ; Rats* ; Spinal Cord

OBJECTIVETo establish the computer-based video-tracking conditioned place preference (CPP) system in mice.

METHODSThe CPP system was composed of computer, camera, soundproof box, shuttle box and analytical software. The results of morphine-induced conditioned place preference were used to evaluate the experiment system. And the effect of morphine-induced locomotor activity in drug-paired compartment was studied in mice.

RESULTSLow (1 mg/kg, i.p.), moderate (3 mg/kg, 5 mg/kg, i.p.) and high (10 mg/kg, i.p.) dose of morphine significantly prolonged the time mice spent in drug-paired compartment compared with saline, but there was no dose-response relation. Moderate and high dose of morphine significantly enhanced locomotor activity, among which 5 mg/kg and 10 mg/kg morphine induced behavior sensitization in drug-paired compartment during the conditioning sessions.

CONCLUSIONThe computer-based video-tracking conditioned place preference experiment system in mice established successfully is reliable and stable.

Animals ; Automatic Data Processing ; Conditioning (Psychology) ; drug effects ; physiology ; Male ; Mice ; Mice, Inbred ICR ; Models, Animal ; Morphine ; pharmacology ; Motor Activity ; drug effects ; Narcotics ; pharmacology ; Opioid-Related Disorders ; physiopathology ; psychology ; Video Recording

The purpose of this study is to determine 1) whether morphine postconditiong (MPostC) can attenuate the intercellular adhesion molecules-1 (ICAM-1) expression after reoxygenation injury and 2) the subtype(s) of the opioid receptors (ORs) that are involved with MPostC. Human umbilical vein endothelial cells (HUVECs) were subjected to 6 hr anoxia followed by 12 hr reoxygenation. Three morphine concentrations (0.3, 3, 30 microM) were used to evaluate the protective effect of MPostC. We also investigated blockading the OR subtypes' effects on MPostC by using three antagonists (a micro-OR antagonist naloxone, a kappa-OR antagonist nor-binaltorphimine, and a delta-OR antagonist naltrindole) and the inhibitor of protein kinase C (PKC) chelerythrine. As results, the ICAM-1 expression was significantly reduced in the MPostC (3, 30 microM) groups compared to the control group at 1, 6, 9, and 12 hours reoxygenation time. As a consequence, neutrophil adhesion was also decreased after MPostC. These effects were abolished by coadministering chelerythrine, nor-binaltorphimine or naltrindole, but not with naloxone. In conclusion, it is assumed that MPostC could attenuate the expression of ICAM-1 on endothelial cells during reoxygenation via the kappa and delta-OR (opioid receptor)-specific pathway, and this also involves a PKC-dependent pathway.
Animals ; Benzophenanthridines/pharmacology ; Endothelial Cells/cytology/*drug effects/*metabolism ; Endothelium, Vascular/cytology ; Humans ; Intercellular Adhesion Molecule-1/genetics/*metabolism ; Morphine/*pharmacology ; Naloxone/pharmacology ; Naltrexone/analogs & derivatives/pharmacology ; Narcotic Antagonists/pharmacology ; Narcotics/*pharmacology ; Protein Isoforms/metabolism ; Protein Kinase C/antagonists & inhibitors/metabolism ; Receptors, Opioid/metabolism ; Reperfusion Injury/*metabolism ; Signal Transduction/physiology ; Umbilical Veins/cytology

OBJECTIVETo observe the effects of gamma-aminobutyric acid (GABA) on the electric activities of pain-excited neurons (PEN) in nucleus accumbens (NAc) in central nervous system (CNS) of morphine-dependent rats.

METHODSAfter GABA or the GABA(A)-receptor antagonist, bicuculline (Bic), was injected into cerebral ventricles or NAc, right sciatic nerve was stimulated by electrical pulses, which was considered as traumatic pain stimulation. Extracellular recordings methods were used to record the electric activities of PEN in NAc.

RESULTSWhen GABA was injected into intracerebroventricle (ICV) as well as NAc, it could decrease the pain-evoked discharge frequency and prolong the latency of PEN. Bic could interdict the above effects of GABA on the electric activities of PEN.

CONCLUSIONExogenous GABA might have an inhibitory effect on the central pain adjustment. Furthermore, GABA and GABA(A) receptor participate and mediate the traumatic information transmission process in CNS.

Action Potentials ; drug effects ; physiology ; Animals ; Bicuculline ; pharmacology ; Disease Models, Animal ; Drug Administration Schedule ; Electric Stimulation ; adverse effects ; Female ; GABA Antagonists ; pharmacology ; Injections, Intraventricular ; methods ; Male ; Morphine ; administration & dosage ; Morphine Dependence ; etiology ; pathology ; physiopathology ; Narcotics ; administration & dosage ; Nucleus Accumbens ; metabolism ; physiopathology ; Pain ; etiology ; physiopathology ; Pain Threshold ; drug effects ; physiology ; Rats ; Rats, Wistar ; Reaction Time ; drug effects ; physiology ; Time Factors ; gamma-Aminobutyric Acid ; metabolism ; pharmacology

OBJECTIVETo investigate the modulatory effects of morphine on the susceptibility to pentylenetetrazole-induced seizures, and the involvement of endogenous histamine in this process.

METHODSBoth the wild-type (WT) mice and histidine decarboxylase (a key enzyme for histamine biosynthesis) deficient (HDC-KO) mice were subcutaneously injected with different doses of morphine, and 1 hour later the pentylenetetrazole solution (1.5 %) was infused into the tail vein at a constant rate of 0.3 ml/min. The minimal dose of pentylenetetrazole (mg/kg) needed to induce myoclonic jerks and clonus convulsion was recorded as the thresholds of seizures.

RESULTIn WT mice, morphine dose-dependently decreased the thresholds of both myoclonic jerks and clonus convulsion. In HDC-KO mice, morphine at 10 mg/kg only significantly decreased the threshold of myoclonic jerks from (38.6 +/-2.9)mg/kg to (32.5 +/-0.7)mg/kg, but had no significant effect on the threshold of clonus convulsion [from (51.8 +/-2.1)mg/kg to (47.6 +/-1.2)mg/kg]. In addition, the value of decreased myoclonic jerks (15.8 +/-1.4)% and clonus convulsion (8.3 +/-0.9)% thresholds were much lower in HDC-KO mice than in WT mice [(26.1 +/-2.5)% and (20.8 +/-2.4)%, respectively].

CONCLUSIONMorphine can decrease the thresholds of pentylenetetrazole in induction of seizure, and the endogenous histamine may be involved in this process.

Animals ; Disease Susceptibility ; chemically induced ; metabolism ; physiopathology ; Dose-Response Relationship, Drug ; Histamine ; metabolism ; physiology ; Histidine Decarboxylase ; genetics ; metabolism ; Male ; Mice ; Mice, Knockout ; Morphine ; pharmacology ; Myoclonus ; chemically induced ; metabolism ; physiopathology ; Narcotics ; pharmacology ; Pentylenetetrazole ; Random Allocation ; Seizures ; chemically induced ; genetics ; physiopathology ; Sensory Thresholds ; drug effects