OBJECTIVETo establish a pig model of chronic external counterpulsation.

METHODSTwelve pigs were anaesthetized with sodium pentobarbital (< or =30 mg/kg.b.w.) and 846 mixture (< or =0.1 ml/kg.b.w.) and counterpulsed in a lateral position for 2 h every two days (totally 36 h) with 0.025 to 0.04 MPa/cm(2) pressure.

RESULTSExternal counterpulsation was successfully completed in all the animals. Combined administration of sodium pentobarbital and 846 mixture resulted in good anesthetic effect with reduced anesthetic dosage and minimal side effect on the viscera (the liver, kidney and heart, etc).

CONCLUSIONThe pig model of chronic external counterpulsation has been successfully established. Combined use of sodium pentobarbital and 846 mixture is recommended for chronic external counterpulsation.

Anesthesia, General ; methods ; Animals ; Animals, Newborn ; Assisted Circulation ; Counterpulsation ; methods ; Models, Animal ; Pentobarbital ; administration & dosage ; Swine

The effects of sevoflurane and subsequent administration of diltiazem on intrapulmonary shunt and oxygenation were studied in pentobarbital anesthetized dogs. After inhalation of 1MAC of sevoflurane and subsequent intravenous administration of clinical dose of diltiazem (loading dose 0.2 mg/kg, maintenance dose 0.01 mg/kg/min), there were no changes in cardiac output, arterial oxygen tension, mixed venous oxygen tension, oxygen transport, oxygen consumption, intrapul-monary shunt ratio, pulmonary vascular resistance, alveolar-arterial oxygen difference. After intravenous administration of diltiazem with bolus (0.4 mg/kg) and maintenance dose (0.02 mg/ kg/min), pulmonary vascular resistance was significantly decreased (p<0.05) but the other parameters indicating pulmonaruy hemodynamics and oxygenation were unchanged. These results suggest that concomittent use of the two classes of drugs is not induce significant changes in pulmonary hemodynamic and oxygenation, and can be used safely in patient with normal cardiopulmonary function when clinical concentration of both were used.
Administration, Intravenous ; Anesthesia* ; Anesthetics ; Animals ; Cardiac Output ; Diltiazem* ; Dogs* ; Hemodynamics ; Humans ; Inhalation ; Oxygen ; Oxygen Consumption ; Pentobarbital ; Vascular Resistance

BACKGROUND: Although recent studies have demonstrated that infusion of L-arginine reduces myocardial necrotic area during prolonged ischemia, its effects on transient postischemic myocardial dysfunction(myocardial stunning) and microvascular dyfunction(vascular stunning) are not well known. To investigate whether intravenous administration of L-arginine, physiological nitric oxide(NO) precursor, during reperfusion would attenuate postischemic myocardial dysfunction and microvascular dysfunction, 15 open-chest dogs were studied. METHODS: In 15 pentobarbital anesthesized open-chest dogs, left circumflex coronary artery was occluded for 20 minutes and was followed by a reperfusion for 60 minutes. L-Arginine(30mg/kg)(L-arginine group, n=8) or saline(control group, n=7) was given intravenously by a bolus 1 minute before reperfusion and was followed by a continuous infusion(10mg/kg/min) for 30 minutes during reperfusion. Before coronary occlusion and 60 minutes after reperfusion, coronary blood flow(CBF) and coronary vascular resistance(CVR) wre measured after intracoronary injection of each of acetylcholine(0.01/kg) and adenosine(1.5/kg), and reactive hyperemia with coronary occlusion(RH20) for 20 seconds was measured. Myocardial segment thickening in the area of ischemia-reperfusion was measured using 2D-echocardiography. The echocardiographic images were digitized and analyzed by cardiac image analyzer. RESULTS: The results obtained 60 minutes after reperfusion were as follows. 1) CBF was decreased by 41% in L-arginine group vs 30.1% in control group(p < 0.05) and CVR was increased by 83.9% in L-arginine group vs 19.3% in control group after 60 minutes of reperfusion, compared with pre-occlusion baseline values. 2) Percent change of CBF was decreased in control group(acetylcholine by 25.8%, adenosine by 29.2%, RH20 by 39.8%), while it was increased in L-arginine group(acetylcholine by 60%, adenosine by 22%, RH20 by 26.7%). Percent change of CVR was increased in control group(acetylcholine by 10.5%, adenosine by 6.9%, RH20 by 21%), but it was decreased in L-arginine group(acetylcholine by 10%, adenosine by 6.6%, RH20 by 1.6%). Increase of CBF and decrease of CVR were significant on acetylcholine and RH20 between control group and L-arginine group. 3) Fraction of myocardial segment thickening was significantly decreased in L-arginine group(by 80%) compared with control group(by 61.7%, p < 0.05). CONCLUSIONS: The finding that L-arginine depressed post-ischemic myocardial contractil function suggests that systemic infusion of L-arginine has unfavorable effect on myocardial stunning. In contrast, the finding that L-arginine improved CBF and CVR with acetylcholine and adenosine and reactive hyperemia indicates that L-arginine may exert a beneficial effect on vascular stunning. These results suggest that L-arginine may have independent effects on myocardial stunning and vascular stunning.
Acetylcholine ; Adenosine ; Administration, Intravenous ; Animals ; Arginine* ; Coronary Occlusion ; Coronary Vessels ; Dogs* ; Echocardiography ; Hyperemia ; Ischemia ; Myocardial Reperfusion ; Myocardial Stunning ; Nitric Oxide ; Pentobarbital ; Reperfusion

Focal cerebral ischemia was made in 20 adult cats by transorbital middle cerebral artery occlusion (MCAO) under pentobarbital anesthesia. Arterial blood gas, systemic arterial blood pressure (SABP), intracranial pressure (ICP), and regional cerebral blood flow (rCBF) on ectosylvian, suprasylvian, and marginal gyrus of the left hemisphere by hydrogen clearance were measured for 30 minutes before and 120 minutes after middle cerebral artery occlusion. Ten animals were treated with 20 mg/kg of pentoxifylline (PTF) and ten animals with 1ml/kg of normal saline as the control group for 30 minutes before and 30 minutes after middle cerebral artery occlusion. There was no beneficial effect of pentoxifylline (Trental(R)) on basal blood flow over left hemisphere before middle cerebral artery occlusion. Regional cerebral blood flow was highly significantly improved on the marginal gyrus (MG) for 90 minutes after middle cerebral artery occlusion, more remarkable for initial 60 minutes (P<0.01), and also significantly restored on suprasylvian gyrus (SSG) for initial 60 minutes by pentoxifylline (P<0.05). However, pentoxifylline failed to improve regional cerebral flow on extosylvian gyrus (ESG) which was considered dense core of infarct area due to middle cerebral artery occlusion in cat. In addition, pentoxifylline had significant hypotensive effect during intravenous administration for 60 minutes (P<0.05). These findings suggest the possibility of pentoxifylline to ameliorate hemorheological property rather than vasodilating effect in the collaterally perfused area around dense infarct.
Administration, Intravenous ; Adult ; Anesthesia ; Animals ; Arterial Pressure ; Brain Ischemia ; Cats ; Cerebral Infarction* ; Hemorheology ; Humans ; Hydrogen ; Infarction, Middle Cerebral Artery ; Intracranial Pressure ; Pentobarbital ; Pentoxifylline*

This study was investigated to know whether pachymic acid (PA), one of the predominant triterpenoids in Poria cocos (Hoelen) has the sedative-hypnotic effects, and underlying mechanisms are mediated via gamma-aminobutyric acid (GABA)-ergic systems. Oral administration of PA markedly suppressed locomotion activity in mice. This compound also prolonged sleeping time, and reduced sleep latency showing synergic effects with muscimol (0.2 mg/kg) in shortening sleep onset and enhancing sleep time induced by pentobarbital, both at the hypnotic (40 mg/kg) and sub-hypnotic (28 mg/kg) doses. Additionally, PA elevated intracellular chloride levels in hypothalamic primary cultured neuronal cells of rats. Moreover, Western blotting quantitative results showed that PA increased the amount of protein level expression of GAD65/67 over a broader range of doses. PA increased alpha- and beta-subunits protein levels, but decreased gamma-subunit protein levels in GABA(A) receptors. The present experiment provides evidence for the hypnotic effects as PA enhanced pentobarbital-induced sleeping behaviors via GABA(A)-ergic mechanisms in rodents. Taken together, it is proposed that PA may be useful for the treatment of sleep disturbed subjects with insomnia.
Administration, Oral ; Animals ; Blotting, Western ; Cocos ; gamma-Aminobutyric Acid ; Hypnotics and Sedatives ; Locomotion ; Mice* ; Muscimol ; Neurons ; Pentobarbital ; Poria ; Rats ; Receptors, GABA-A ; Rodentia ; Sleep Initiation and Maintenance Disorders

Angelicae Gigantis Radix (AGR, Angelica gigas) has been used for a long time as a traditional folk medicine in Korea and oriental countries. Decursinol angelate (DCA) is structurally isomeric decursin, one of the major components of AGR. This study was performed to confirm whether DCA augments pentobarbital-induced sleeping behaviors via the activation of GABA(A)-ergic systems in animals. Oral administration of DCA (10, 25 and 50 mg/kg) markedly suppressed spontaneous locomotor activity. DCA also prolonged sleeping time, and decreased the sleep latency by pentobarbital (42 mg/kg), in a dose-dependent manner, similar to muscimol, both at the hypnotic (42 mg/kg) and sub-hypnotic (28 mg/kg) dosages. Especially, DCA increased the number of sleeping animals in the sub-hypnotic dosage. DCA (50 mg/kg, p.o.) itself modulated sleep architectures; DCA reduced the counts of sleep/wake cycles. At the same time, DCA increased total sleep time, but not non-rapid eye movement (NREM) and rapid eye movement (REM) sleep. In the molecular experiments. DCA (0.001, 0.01 and 0.1 µg/ml) increased intracellular Cl- influx level in hypothalamic primary cultured neuronal cells of rats. In addition, DCA increased the protein expression of glutamic acid decarboxylase (GAD(65/67)) and GABA(A) receptors subtypes. Taken together, these results suggest that DCA potentiates pentobarbital-induced sleeping behaviors through the activation of GABA(A)-ergic systems, and can be useful in the treatment of insomnia.
Administration, Oral ; Angelica ; Animals ; Electroencephalography ; Eye Movements ; Glutamate Decarboxylase ; Korea ; Medicine, Traditional ; Motor Activity ; Muscimol ; Neurons ; Pentobarbital ; Rats ; Receptors, GABA-A ; Rodentia* ; Sleep Initiation and Maintenance Disorders ; Sleep, REM

In the event of an infectious disease outbreak in cattle, carcasses must be disposed of in a rapid and contained manner. This brief communication details injection of a barbiturate to euthanize cattle inoculated with Escherichia coli O157:H7 followed by carcass composting in a manner that prevents the spread of infectious agents.
Animals ; Cattle ; Cattle Diseases/*microbiology ; Disease Outbreaks/*veterinary ; Escherichia coli Infections/microbiology/*veterinary ; *Escherichia coli O157 ; Euthanasia, Animal/*methods ; Hypnotics and Sedatives/administration & dosage/pharmacology ; Male ; Pentobarbital/administration & dosage/*pharmacology ; Soil

Sinomenium acutum has been long used in the preparations of traditional medicine in Japan, China and Korea for the treatment of various disorders including rheumatism, fever, pulmonary diseases and mood disorders. Recently, it was reported that Sinomenium acutum, has sedative and anxiolytic effects mediated by GABA-ergic systems. These experiments were performed to investigate whether sinomenine (SIN), an alkaloid derived from Sinomenium acutum enhances pentobarbital-induced sleep via γ-aminobutyric acid (GABA)-ergic systems, and modulates sleep architecture in mice. Oral administration of SIN (40 mg/kg) markedly reduced spontaneous locomotor activity, similar to diazepam (a benzodiazepine agonist) in mice. SIN shortened sleep latency, and increased total sleep time in a dose-dependent manner when co-administrated with pentobarbital (42 mg/kg, i.p.). SIN also increased the number of sleeping mice and total sleep time by concomitant administration with the sub-hypnotic dosage of pentobarbital (28 mg/kg, i.p.). SIN reduced the number of sleep-wake cycles, and increased total sleep time and non-rapid eye movement (NREM) sleep. In addition, SIN also increased chloride influx in the primary cultured hypothalamic neuronal cells. Furthermore, protein overexpression of glutamic acid decarboxylase (GAD(65/67)) and GABA(A) receptor subunits by western blot were found, being activated by SIN. In conclusion, SIN augments pentobarbital-induced sleeping behaviors through GABA(A)-ergic systems, and increased NREM sleep. It could be a candidate for the treatment of insomnia.
Administration, Oral ; Animals ; Anti-Anxiety Agents ; Benzodiazepines ; Blotting, Western ; China ; Diazepam ; Eye Movements* ; Fever ; Glutamate Decarboxylase ; Japan ; Korea ; Lung Diseases ; Medicine, Traditional ; Mice ; Mood Disorders ; Motor Activity ; Neurons ; Pentobarbital ; Receptors, GABA-A ; Rheumatic Diseases ; Rodentia* ; Sinomenium* ; Sleep Initiation and Maintenance Disorders