| Budget Amount *help |
¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 2005: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 2004: ¥1,200,000 (Direct Cost: ¥1,200,000)
|
|---|
| Research Abstract |
Endogenous γ-hydroxybutyric acid (GHB) levels in various postmortem fluid samples of 25 autopsy cases with no or little putrefaction were measured by headspace gas chromatography after GHB was converted to γ-butyrolactone. Endogenous GHB levels were significantly higher in femoral venous blood (4.6±3.4μg/ml, n=23) than in cerebrospinal fluid (1.8±1.5μg/ml, n=9), vitreous humor (0.9±1.7μg/ml, n=8), bile (1.0±1.1μg/ml, n=9) and urine (0.6±1.2μg/ml, n=12). GHB levels were similar in blood samples taken from different sites. Cut-off limits of 30 and 10μg/ml can be proposed for blood and urine, respectively, to discriminate between exogenous and endogenous GHB in decedents showing no or little putrefaction.
We have devised a simple method for detecting GHB in blood and urine by gas chromatography and liquid-liquid extraction with a back-extraction step for purification. The sensitivity of this method was approximately three times as high as that of the headspace gas chromatographic method.
Endogenous levels of GHB in urine samples obtained from 20 healthy volunteers were measured by gas chromatography combined with liquid-liquid extraction. There were 4 average drinkers (males), 4 average smokers (males), and 12 nonsmokers/nondrinkers (7 males and 5 females). The urinary levels of GHB in males were higher in smokers (0.52±0.37μg/ml) than in nonsmokers/nondrinkers (0.28±0.21μg/ml) and drinkers (0.23±0.04μg/ml). No gender differences were observed in the urinary levels of endogenous GHB.
When 2 g/kg of ethanol, 3 mg/kg of nicotine, 5 mg/kg of methamphetamine hydrochloride, 5 mg/kg of cocaine hydrochloride, 5 mg/kg of morphine hydrochloride, or 5 mg/kg of sodium amobarbital was subcutaneously administered to rabbits once a day for 5 days, no changes in endogenous GHB levels in blood were observed. Short term administration of those drugs of abuse may not affect endogenous production of GHB.
|
