Most cited article - PubMed ID 9342031
Urine organic acid profiling by capillary gas chromatography after a simple sample pretreatment
Ibotenic acid and muscimol are substances which mostly participate in psychotropic properties of Amanita pantherina and Amanita muscaria. They are rapidly absorbed from the gastrointestinal tract and readily excreted in urine. The poisoning with A. pantherina is in the majority of cases accidental because it can be easily mistaken for the edible species (Amanita rubescens, Amanita spissa and Macrolepiota procera). Intoxication with A. muscaria is mostly intentional for recreational purposes. Prognosis of the poisoning is generally good; lethal cases are rare. Mushroom poisoning is often proved by microscopic examination of spores in the stomach or intestinal content. Authors of this article introduce an instrumental method of proving A. pantherina or A. muscaria poisoning. The article describes the isolation of ibotenic acid and muscimol from urine, the derivatization step and the determination of these compounds by gas chromatography/mass spectrometry. Isolation of these alkaloids from urine was performed on a strong cation exchanger (Dowex® 50W X8), and the elution and derivatization of the alkaloids were made in one step with ethyl chloroformate in aqueous solution of sodium hydroxide with the addition of ethanol and pyridine. Cycloserine was used as internal standard. By this method, concentrations of ibotenic acid and muscimol in the urine of four persons intoxicated with A. pantherina were determined. In this study, mass spectra of derivatized ibotenic acid and muscimol are shown, and validation of the method is described.
- MeSH
- Amanita chemistry MeSH
- Adult MeSH
- Ibotenic Acid urine MeSH
- Middle Aged MeSH
- Humans MeSH
- Muscimol urine MeSH
- Mushroom Poisoning diagnosis urine MeSH
- Gas Chromatography-Mass Spectrometry MeSH
- Psychotropic Drugs urine MeSH
- Aged MeSH
- Forensic Toxicology MeSH
- Check Tag
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Validation Study MeSH
- Names of Substances
- Ibotenic Acid MeSH
- Muscimol MeSH
- Psychotropic Drugs MeSH
BACKGROUND: Drosophila melanogaster is a chill-susceptible insect. Previous studies on this fly focused on acute direct chilling injury during cold shock and showed that lower lethal temperature (LLT, approximately -5°C) exhibits relatively low plasticity and that acclimations, both rapid cold hardening (RCH) and long-term cold acclimation, shift the LLT by only a few degrees at the maximum. PRINCIPAL FINDINGS: We found that long-term cold acclimation considerably improved cold tolerance in fully grown third-instar larvae of D. melanogaster. A comparison of the larvae acclimated at constant 25°C with those acclimated at constant 15°C followed by constant 6°C for 2 d (15°C→6°C) showed that long-term cold acclimation extended the lethal time for 50% of the population (Lt(50)) during exposure to constant 0°C as much as 630-fold (from 0.137 h to 86.658 h). Such marked physiological plasticity in Lt(50) (in contrast to LLT) suggested that chronic indirect chilling injury at 0°C differs from that caused by cold shock. Long-term cold acclimation modified the metabolomic profiles of the larvae. Accumulations of proline (up to 17.7 mM) and trehalose (up to 36.5 mM) were the two most prominent responses. In addition, restructuring of the glycerophospholipid composition of biological membranes was observed. The relative proportion of glycerophosphoethanolamines (especially those with linoleic acid at the sn-2 position) increased at the expense of glycerophosphocholines. CONCLUSION: Third-instar larvae of D. melanogaster improved their cold tolerance in response to long-term cold acclimation and showed metabolic potential for the accumulation of proline and trehalose and for membrane restructuring.
- MeSH
- Acclimatization * MeSH
- Amino Acids metabolism MeSH
- Survival Analysis MeSH
- Time Factors MeSH
- Drosophila melanogaster metabolism physiology MeSH
- Larva metabolism physiology MeSH
- Fatty Acids metabolism MeSH
- Carbohydrate Metabolism MeSH
- Metabolome * MeSH
- Cold Temperature * adverse effects MeSH
- Polymers metabolism MeSH
- Freezing adverse effects MeSH
- Animals MeSH
- Check Tag
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Amino Acids MeSH
- Fatty Acids MeSH
- Polymers MeSH
- polyol MeSH Browser
The larva of the drosophilid fly, Chymomyza costata, is probably the most complex metazoan organism that can survive submergence in liquid nitrogen (-196 °C) in a fully hydrated state. We examined the associations between the physiological and biochemical parameters of differently acclimated larvae and their freeze tolerance. Entering diapause is an essential and sufficient prerequisite for attaining high levels of survival in liquid nitrogen (23% survival to adult stage), although cold acclimation further improves this capacity (62% survival). Profiling of 61 different metabolites identified proline as a prominent compound whose concentration increased from 20 to 147 mM during diapause transition and subsequent cold acclimation. This study provides direct evidence for the essential role of proline in high freeze tolerance. We increased the levels of proline in the larval tissues by feeding larvae proline-augmented diets and found that this simple treatment dramatically improved their freeze tolerance. Cell and tissue survival following exposure to liquid nitrogen was evident in proline-fed nondiapause larvae, and survival to adult stage increased from 0% to 36% in proline-fed diapause-destined larvae. A significant statistical correlation was found between the whole-body concentration of proline, either natural or artificial, and survival to the adult stage in liquid nitrogen for diapause larvae. Differential scanning calorimetry analysis suggested that high proline levels, in combination with a relatively low content of osmotically active water and freeze dehydration, increased the propensity of the remaining unfrozen water to undergo a glass-like transition (vitrification) and thus facilitated the prevention of cryoinjury.
- MeSH
- 1-Pyrroline-5-Carboxylate Dehydrogenase deficiency MeSH
- Acclimatization drug effects MeSH
- Principal Component Analysis MeSH
- Survival Analysis MeSH
- Diet MeSH
- Calorimetry, Differential Scanning MeSH
- Drosophilidae drug effects physiology MeSH
- Nitrogen pharmacology MeSH
- Adaptation, Physiological drug effects MeSH
- Cryopreservation * MeSH
- Larva drug effects physiology MeSH
- Osmosis drug effects MeSH
- Proline metabolism MeSH
- Proline Oxidase deficiency MeSH
- Glass MeSH
- Feeding Behavior drug effects MeSH
- Body Water drug effects MeSH
- Amino Acid Metabolism, Inborn Errors physiopathology veterinary MeSH
- Freezing MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- 1-Pyrroline-5-Carboxylate Dehydrogenase MeSH
- Nitrogen MeSH
- Proline MeSH
- Proline Oxidase MeSH