Changes in cholinergic function in the frontal cortex and hippocampus of rat exposed to ethanol and acetaldehyde.

Our previous microdialysis study demonstrated that both ethanol (EtOH) and acetaldehyde (ACe) decrease in vivo acetylcholine (ACh) release in the medial frontal cortex of freely moving rats. To better understand the mechanisms of EtOH and ACe's effects on the cholinergic system in the brain, choline acetyltransferase (ChAT) and acetylcholinesterase (AChE) expression was examined at 40 and 240 min after a dose of EtOH (1 g/kg) in the rat frontal cortex and hippocampus. The control group was treated with 0.9% saline, and other groups received EtOH or cyanamide (CY, 50 mg/kg, a potent aldehyde dehydrogenase inhibitor) and 60 min later by EtOH intraperitoneally. Reverse-transcription polymerase chain reaction (RT-PCR) analysis revealed that ChAT mRNA levels were decreased by 72.8% and 71.6% in the EtOH and CY+EtOH groups, respectively, at 40 min after EtOH injection compared with saline in the frontal cortex. The hippocampal ChAT levels were reduced by 76.5% and 53.0% in the EtOH and CY+EtOH groups, respectively, at this time. CY+EtOH-induced depletion in ChAT mRNA levels was markedly higher than EtOH in the hippocampus. A similar decrease pattern of ChAT was observed at protein levels as determined by Western blot, but the reduced ChAT levels were significantly higher in the CY+EtOH group as compared with the EtOH group both in the frontal cortex and hippocampus. At 240 min after EtOH injection, the EtOH group had no effect on ChAT at mRNA levels, as compared with saline, whereas CY+EtOH group induced a significant decrease in ChAT mRNA expression to 62.0% and 65.5% in the frontal cortex and hippocampus, respectively. These data were consistent with the results of the Western blot analysis. AChE expression at mRNA levels was not changed at either 40 or 240 min after EtOH dosing in either of these groups in the frontal cortex and hippocampus. Within 40 and 240 min, a statistically significant difference in ChAT expression at mRNA and protein levels was found in the EtOH and CY+EtOH groups both in the frontal cortex and hippocampus. The data obtained from this study demonstrate that EtOH and ACe concentrations decreased ChAT expression at 40 and 240 min after EtOH administration in the frontal cortex and hippocampus, and this result suggests that reduced ChAT expression is strongly related to a decrease in ACh release in the rat brain.

Acute ethanol decreases NPY mRNA but not POMC mRNA in the arcuate nucleus.

The acute effects of ethanol and acetaldehyde on neuropeptide mRNA expression in the arcuate nucleus (ARC) was assessed. Acetaldehyde was increased in blood following ethanol with cyanamide (a potent inhibitor of aldehyde dehydrogenase) administration. Acetaldehyde is a toxin which can cause a variety of adverse effects following ethanol ingestion in some Oriental people with a genetic lower activity of aldehyde dehydrogenase. Neuropeptide Y (NPY) mRNA levels in ARC were significantly decreased in response to ethanol in the presence or absence of cyanamide compared to control. In contrast, proopiomelanocortin mRNA in ARC was not changed. These novel findings suggest that ethanol suppresses NPY gene expression in ARC and may play a role in ethanol-induced changes in neuronal function.

Short-term ethanol exposure alters calbindin D28k and glial fibrillary acidic protein immunoreactivity in hippocampus of mice.

The effects of a short-term ethanol treatment on hippocampus have been studied in mice exhibiting intoxication signs. The alterations of neurons and astrocytes as well as quantitative changes of calbindin D28k-immunoreactivity and glial fibrillary acidic protein-immunoreactivity (GFAP-IR) in selected regions of the dorsal hippocampus were examined using anti-calbindin and anti-GFAP monoclonal anti-body (mAb), respectively. The administration of 6% (v/v) ethanol during first week led to the neuronal death and decrease of the total number of calbindin-IR neurons in the examined brain regions. Moreover, the calbindin positive neurons were shown to have diminished processes following short-term ethanol exposure. These neuronal changes were associated with the increase of the GFAP-IR astrocytes. Hypertrophy of cell bodies and cytoplasmic processes of reactive astrocytes were also seen. In addition, dense, thick and highly-stained GFAP-IR cells with long processes in granular cell layer appeared entering into molecular layer of dentate gyrus. In agreement with the discrepancy percentage of neuronal cell loss and increase of reactive astrocytes detected by calbindin and GFAP-IR using image quantitative analysis, the regional differences in the vulnerability to the neurotoxic effects following short-term ethanol exposure were found: CA3>CA2>CA1>DG. These findings also illustrate the importance of correlation between calbindin and GFAP-IR when determining the morphological alteration of neuron and astroglial following short-term ethanol treatment. The disruption of calbindin and GFAP could affect neuronal-astroglial interaction, resulting in disturbance of behaviors dependent on hippocampus.

Direct dissolution of gallstones with methyl tert-butyl ether (MTBE) via endoscopic transpapillary catheterization in the gallbladder (ETCG).

In a pilot study of direct dissolution therapy of gallstones with methyl tert-butyl ether (MTBE), endoscopic transpapillary catheterization in the gallbladder (ETCG) was performed. Complete dissolution was seen in 8 out of 12 (66%) patients and partial dissolution was seen in 2 (16%) patients. In one of the 8 complete dissolution patients, combined extracorporeal shock wave lithotripsy (ESWL) and dissolution therapy was carried out successfully. These 8 patients were followed up for 12-20 months with regular ultrasonography. During this period, 1 patient underwent laparoscopic cholecystectomy due to stone recurrence. Thickening of the gallbladder wall was seen in 2 patients, but there were no other complications. Using Tsuchiya's classification based on ultrasound, complete dissolution was seen in type Ia stones. This pilot study suggests that the direct dissolution of gallstones with MTBE via ETCG might be a useful and safe non-invasive treatment in patients with cholesterol stones in preserved gallbladders.

IgG subclass distributions of anti-horse serum antibodies and natural venom-antibodies produced in response to antivenom injection or snake bite in humans.

The Japanese Mamushi (Agkistrodon halys blomhoffi, BOIE) is the most common snake in Japan. Bite victims treated with antivenom (horse serum) can produce antibodies against the horse serum and the snake venom. We studied distributions of the IgG subclasses of both these antibodies produced in response to antivenom injection and snake bite. We found that IgG1 and IgG4 of each antibody in the victims' serum were present for a long period of time.

Effect of ethanol on fatal carbon monoxide poisoning in awake mice [correction of rats].

The effect of ethanol on fatal carbon monoxide (CO) poisoning was investigated in mice injected intraperitoneally with ethanol. Ethanol (1.5 and 3.0 g/kg) was injected 15 min prior to exposure to gas containing 6.6% CO. The survival period was significantly lengthened with ethanol in proportion to the doses injected, although the carboxyhemoglobin (CO-Hb) saturation level in postmortem blood was almost the same in all groups. On the other hand, the CO-Hb level in the blood of mice injected with ethanol was significantly lower than that of control mice during the early exposure period when all mice were still alive. Our results showed that the acute ethanol injection did not influence the CO-Hb saturation level in blood at death, but did affect the duration of survival, probably because of ethanol's ability to decrease blood flow and CO intake.

Relationship between facial flushing and blood acetaldehyde levels after alcohol intake.

Normal subjects were divided into two groups, i.e., those showing, and those not showing, facial flushing after consuming a small amount of alcohol. In the flushing group, increases of pulse rate, facial skin temperature and carotid arterial pressure and blood flow rate, as well as changes of digital plethysmogram and electrocardiogram, were found together with a conspicuous rise in blood acetaldehyde levels after the drinking. However, significant changes of the signs as mentioned above and elevation of blood acetaldehyde did not occur in the non-flushing group. The maximum blood alcohol levels and the rate of alcohol elimination showed not difference between these two groups. Furthermore, urinary excretions of epinephrine and norepinephrine increased in the flushing cases after the drinking.

Possible involvement of kinins in cardiovascular changes after alcohol intake.

Japanese healthy male subjects were divided into two groups, i.e., a normal aldehyde dehydrogenase (ALDH) group with a low Km isozyme of ALDH for acetaldehyde, and a deficient group without it. After intake of 0.4 g/kg alcohol, the deficient group showed high levels of blood acetaldehyde, facial flushing including an increased pulse rate and a fall in diastolic blood pressure, while the normal group did not manifest these changes. In the deficient group, the total kininogen concentration gradually decreased after alcohol intake due to a reduction in low molecular weight kininogen, and plasma prekallikrein remained unchanged. The normal group showed no significant changes in any of these values after alcohol intake. In an in vitro study with pooled plasma, the low concentrations of urinary kallikrein caused a decrease in the low molecular weight kininogen only. These results suggest that kinins released by acetaldehyde-induced activation of glandular kallikreins are associated with the changes in cardiovascular symptoms in deficient group which display flushing after alcohol intake.

Alcohol sensitivity related to polymorphism of alcohol-metabolizing enzymes in Japanese.

Normal Japanese subjects were divided into two groups, i.e., one with both low and high Km isozymes of aldehyde dehydrogenase for acetaldehyde, and the other deficient in the low Km isozyme. After intake of 0.4 g/kg alcohol, the deficient subjects showed high level of blood acetaldehyde, facial flushing and the other dysphoric symptoms, including increase of pulse rate, decrease of diastolic blood pressure, changes of pulse wave in the fingertip, and elevation of the arterial pressure and blood flow rate in common carotid arteries as well as increase of plasma catecholamines level. In contrast, subjects with normal ALDH did not show these changes. From the observation of liver specimens obtained at autopsy, the frequency of deficient phenotype of ALDH in Japanese was presumed to be about 36%.

The effect of heating on Y-chromosome detection.

The effect of heating on Y-chromosome detection was investigated. Heat-treated blood was divided into four groups according to the hemolysis pattern obtained by the coil planet centrifuge system. A significant difference between the Y-positive nuclei of males and females was observed up to group III of the hemolysis pattern, and it was possible to determine the sex of the blood donor in spite of karyolysis and degeneration of blood components. However, sex determination of blood in group IV, indicating complete hemolysis, was impossible because of overlapping between male and female Y-chromosome counts. Practical application of this sex determination method was successful even with severely burned cadavers. However, it was suggested that putrefaction together with heat damage made the identification nearly impossible.

An enzyme-linked immunosorbent assay for plasma-paraquat levels of poisoned patients.

To investigate the efficacy of medical treatments, plasma-paraquat levels were measured in patients who had ingested the liquid weedkiller, Gramoxon, containing paraquat. We determined the levels by an enzyme-linked immunosorbent assay (ELISA) using a murine paraquat-specific monoclonal antibody developed by Niewola et al. (Clin. Chim. Acta, 148 (1985) 149-156). Using this ELISA, concentrations of paraquat in the range 1.56-100 ng/ml could be measured. This assay method had good precision and was suitable for measurement of low levels of paraquat. The therapeutic treatments were most effective on the day of admission. The plasma-paraquat levels of poisoned patients decreased significantly. However, the levels tended to increase again during the pause period of the haemoperfusion and this increase was serious for fatal cases. It is clear that elimination of poison not only from blood but also from tissues is necessary to lower the mortality rate.

A fatal case of oral ingestion of toluene.

A 51-year-old male ingested orally a large quantity of toluene and died about 30 min later. The presence of toluene in body fluids and tissues was confirmed by gas chromatography and gas chromatography/mass spectrometry. Tissue distribution of toluene showed that the liver detected the highest content of toluene (433.5 micrograms/g), except for the stomach contents, followed by pancreas (88.2 micrograms/g), brain (85.3 micrograms/g), heart (62.6 micrograms/g), blood (27.6 micrograms/g), fat (12.2 micrograms/g) and finally cerebrospinal fluid (11.1 micrograms/g).

Toxicological index of paraquat: a new strategy for assessment of severity of paraquat poisoning in 128 patients.

A new assessment of the severity of paraquat poisoning in 128 patients has been developed. It involves toxicological index of paraquat and discriminant function score. This system not only allows a more accurate assessment of severity of the poisoning, but also provides a more reliable prediction of the outcome in an early stage for the purpose of forensic and clinical toxicology.

Blood carbofuran concentrations in suicidal ingestion cases.

We describe four fatal cases due to ingestion of carbofuran, a carbamate insecticide. Carbofuran was detected in the gastric contents using thin layer chromatography (TLC) and gas chromatography/mass spectrophotometry (GC/MS), and quantified in the blood using a gas chromatograph equipped with nitrogen-phosphorus detector (NPD). Fatal concentrations of carbofuran in blood ranged from 0.32 to 11.6 microg/ml.

Hypothalamo-pituitary-adrenal axis activation by administration of cyanamide: a potent inhibitor of aldehyde dehydrogenase.

In this report, we investigated the effects of cyanamide (a potent inhibitor of aldehyde dehydrogenase (ALDH: EC 1.2.1.3)) on hypothalamo-pituitary adrenal (HPA)-axis using in situ hybridization histochemistry and radioimmunoassay. Cyanamide administration resulted in a dose-dependent increase in plasma corticosterone concentrations, significant increases in not only corticotrophin releasing factor (CRF) mRNA, but also arginine vasopressin (AVP) mRNA in the paraventricular nucleus (PVN) and proopiomelanocortin (POMC) mRNA in the anterior pituitary. These results suggest that cyanamide is able to activate the HPA axis at all levels of the axis.

Acute fatal poisoning cases due to furathiocarb ingestion.

Seven cases involving acute fatalities due to ingestion of furathiocarb, a carbamate insecticide, are presented. Furathiocarb was detected in the gastric contents using thin layer chromatography (TLC) and gas chromatography/mass spectrophotometry (GC/MS), and quantified in the blood using a gas chromatograph equipped with a nitrogen-phosphorus detector (NPD). The fatal levels of furathiocarb in the blood ranged from 0.1 to 21.6 micrograms/ml.

Simultaneous determination of bromvalerylurea, bromodiethylacetylurea, and allylisopropylacetylurea in serum and urine by high-performance liquid chromatography with a multiwavelength UV detector and thin-layer chromatography.

A method for rapid detection and identification of bromvalerylurea (BVU), bromodiethylacetylurea (BDU), and allylisopropylacetylurea (AIU) in serum and urine by high-performance liquid chromatography (HPLC) with a multiwavelength UV detector after Sep-Pak C18 cartridge extraction is reported. A Jasco Finepak C18 reversed-phase column was used for the separation. Acetonitrile-distilled water (1:1, v/v) was used as a mobile phase. There was no significant absorption of the three hypnotics in the UV spectra (210-350 nm). However, the absorption of each was higher at the shorter wavelengths. The quantifications for the three hypnotics detected at 210 nm by the chromatogram were linear over the range 0.2-4 micrograms/mL and the detection limits of BVU, BDU, and AIU were 5, 10, and 10 ng as absolute amounts, respectively. The mean recovery yields of BVU, BDU, and AIU by Sep-Pak C18 cartridge extraction were 85.7 +/- 4.1, 98.6 +/- 2.2, and 95.1 +/- 3.5% (n = 5) in serum and 79.5 +/- 3.8, 95.7 +/- 1.8, and 93.0 +/- 4.2% (n = 5) in urine, respectively. An optimal system of thin-layer chromatography for the identification of the hypnotics is also discussed.

A rapid and sensitive quantitation of Dipterex in serum by solid-phase extraction and gas chromatography with flame thermionic detection.

A simple, sensitive, and rapid quantitative method for Dipterex in serum is described. A SepPak C18 cartridge for the extraction and gas chromatography with flame thermionic detection for determination are used. The detection limit is 2.5 ng/mL, and linearity is obtained in the range 5-500 ng/mL.

A rapid, simultaneous determination of paraquat and diquat in serum and urine using second-derivative spectroscopy.

A rapid, simple method based on second-derivative spectroscopy of the simultaneous analysis of paraquat and diquat in serum and urine is described. Paraquat and diquat in serum were deproteinized with sulfosalicylic acid, and those in urine were reduced with NaOH-dithionite solution. A qualitative and quantitative analysis of reduced paraquat and diquat was made at the amplitude peaks of 396-403 nm and 454-464 nm in the second-derivative spectra, respectively. The entire procedure was completed within about 10 minutes for a serum sample and within about 5 minutes for a urine sample. Application of the proposed method on a poisoned patient is also reported.

A rapid and sensitive quantitation of Amitraz in plasma by gas chromatography with nitrogen-phosphorus detection and its application for pharmacokinetics.

We report a simple, sensitive, and rapid quantitation of Amitraz in plasma after Extrelut-3 column extraction by gas chromatography with nitrogen-phosphorus detection (GC-NPD). The plasma sample was diluted four-fold with borate buffer (0.01M, pH 11), put into an Extrelut-3 column, left for 15 min, and then eluted with 15 mL of n-hexane. The n-hexane eluate was evaporated under nitrogen gas flow at room temperature. The residue was reconstituted with 0.1 mL of acetone containing nitrazepam as an internal standard. A 2-microL aliquot was injected into a wide-bore capillary column GC-NPD. The detection limit was 0.5 ng/mL and linearity was obtained in the range of 1-200 ng/mL. Amitraz in the buffer at pH 11 remained stable in a freezer for one week at -20 degrees C. The GC-NPD method was found useful in studying the pharmacokinetics of a single dose intravenous administration of Amitraz to a dog.