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1.
Ethanol is added to unleaded gasoline as an oxygenate to decrease carbon monoxide automobile emissions. This introduces inhalation as a new possible route of environmental exposure to humans. Knowledge of the pharmacokinetics of inhaled ethanol is critical for adequately assessing the dosimetry of this chemical in humans. The purpose of this study was to characterize the pharmacokinetics of inhaled ethanol in male and female B6C3F1 mice and F344 rats and to develop a physiologically based pharmacokinetic (PBPK) model for inhaled ethanol in mice, rats, and humans. During exposure to 600 ppm for 6 hr, steady-state blood ethanol concentrations (BEC) were reached within 30 min in rats and within 5 min in mice. Maximum BEC ranged from 71 microM in rats to 105 microM in mice. Exposure to 200 ppm ethanol for 30 min resulted in peak BEC of approximately 25 microM in mice and approximately 15 microM in rats. Peak BEC of about 10 microM were measured following exposure to 50 ppm in female rats and male and female mice, while blood ethanol was undetectable in male rats. No sex-dependent differences in peak BEC at any exposure level were observed. Species-dependent differences were found following exposure to 200 and 600 ppm. A blood flow limited PBPK model for ethanol inhalation was developed in mice, rats, and humans which accounted for a fractional absorption of ethanol. Compartments for the model included the pulmonary blood and air, brain, liver, fat, and rapidly perfused and slowly perfused tissues. The PBPK model accurately simulated BEC in rats and mice at all exposure levels, as well as BEC reported in human males in previously published studies. Simulated peak BEC in human males following exposure to 50 and 600 ppm ranged from 7 to 23 microM and 86 and 293 microM, respectively. These results illustrate that inhalation of ethanol at or above the concentrations expected to occur upon refueling results in minimal BEC and are unlikely to result in toxicity.  相似文献   

2.
Since allyl alcohol and ethanol are both metabolized by alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH), ethanol could affect allyl-alcohol induced toxicity under in vivo coexposure conditions. Male Sprague-Dawley rats were treated with ethanol (2 g/kg, i.p.) simultaneously or 2 h before with allyl alcohol (40 mg/kg, i.p.). Coexposure to allyl alcohol and ethanol resulted in neither enhancement nor protection in allyl alcohol-induced hepatotoxicity at 24 h. However, markedly increased lethality was observed under our coexposure conditions. Pretreatment with 4-methylpyrazole (4-MP) to inhibit ADH did not result in increased lethality to allyl alcohol or ethanol alone, but significantly reduced the lethality of the combined treatment. In contrast, ALDH inhibition increased the lethality of allyl alcohol alone as well as that of the combined allyl alcohol and ethanol treatment. Kinetic studies revealed that combined treatment with allyl alcohol and ethanol resulted in higher blood allyl alcohol levels compared to allyl alcohol alone, and these were accompanied by greater lethality. ADH inhibition increased allyl alcohol blood levels significantly when rats were treated with allyl alcohol alone or allyl alcohol plus ethanol, leading to protection against lethality. In contrast, ALDH inhibition did not affect blood allyl alcohol levels, but resulted in increased lethality. These data suggest a possible role for a metabolite of allyl alcohol, acrolein, in the increased lethality of allyl alcohol and ethanol coexposure in rats.  相似文献   

3.
The relationship between blood ethanol concentration and hepatic ethanol metabolism commonly is calculated using the Michaelis-Menten equation and a one-compartment model that assumes equality of blood and hepatic ethanol concentrations. However, at low blood concentrations, most of the ethanol arriving at the liver is metabolized, and hepatic ethanol concentrations may fall far below that of the entering blood. We have developed a two-compartment model of ethanol metabolism that accounts for the fall in ethanol concentration that may occur as blood traverses the liver and used this model to make predictions concerning ethanol metabolism at various blood ethanol concentrations. The two-compartment model predicts that near-complete saturation will occur more abruptly and at a lower blood concentration (approximately 3 mM) than is the case with the one-compartment model. Thus, the two-compartment model predicts a near-constant ethanol elimination rate for blood ethanol concentrations above 3 mM (as commonly observed in human subjects), whereas the one-compartment model predicts an increasing elimination rate over the range of concentrations observed in experimental studies. In agreement with observed data, the two-compartment model predicts that first-pass metabolism should be extremely sensitive to the rate of ethanol absorption. Application of this model to previously published data indicated that, when absorption was slowed via concomitant food ingestion, first-pass metabolism accounts for approximately 50% and 10% of ethanol dosages of 0.15 g/kg and 0.3 g/kg, respectively. When ingested without food, there is negligible first-pass metabolism of even very small ethanol dosages (0.15 g/kg). These findings suggest that first-pass metabolism is an unimportant determinant of the blood ethanol response to ingestion of potentially inebriating doses of ethanol.  相似文献   

4.
Previous studies have reported some significant participation by gastric alcohol dehydrogenase (ADH) in alcohol metabolism, similar to that by hepatic ADH. However, the localization of this ADH in the stomach is not yet determined and there has been no study on the localization of ADH in the stomach of alcoholics before and after abstinence from alcohol. The aim of the present study was to reveal any changes between before and after abstinence from alcohol in the immunohistochemical localization of ADH using biopsy specimens from the gastric mucosa. Twenty male alcoholics (aged 47.8 +/- 7.4 yrs) gave signed informed consent for this investigation. Esophago-gastro-duodenoscopy (EGD) and gastric corpus biopsy were performed just before abstinence and at one month later. ADH in the biopsy specimens was immunohistochemically examined with an anti-ADH antibody, using confocal laser scanning microscopy. The fluorescence intensity for ADH was compared for each pair of specimens before and after abstinence from alcohol using an image analyzer. Age, total alcohol consumption, degree of gastritis, and the liver function tests of all patients were also analyzed. The strongly immuno-positive cells for ADH in the gastric mucosa were identified as parietal cells. The fluorescence intensity for ADH was significantly higher in those specimens obtained after abstinence than in those before abstinence (p < 0.005). The immunoreactibility for ADH in the cells assessed by confocal laser scanning microscopy was greatly improved after abstinence of alcohol, suggesting recovered alcohol metabolism in the gastric mucosa after abstinence from alcohol. The present study, demonstrating the cellular ADH localization in the gastric mucosa before and after abstinence from alcohol, may contribute to clarifying gastric alcohol metabolism in alcoholics.  相似文献   

5.
A genetically based animal model of alcoholism has been developed in a relatively short period of 3 years. The new strain is characterized by an intense preference for ethanol over water as well as unique behavioral, neurochemical and other attributes. This new strain, termed high-ethanol-preferring (HEP) rats, was derived initially from selective cross-breeding of a variant strain of female Harlan Sprague-Dawley (SD) rats with the outbred Wistar line of male ethanol-preferring (P) rats. In this study, drinking patterns of both genders were obtained over 10 days by presenting water and ethanol in concentrations ranging from 3% to 30%. To expedite the development of the new strain, only three to five female and male rats served as breeders, which were chosen from all litters on the basis of their maximum g/kg intake integrated with proportion of ethanol to total fluid values. Profiles of intake of preferred concentrations of ethanol were obtained over 24 h of unlimited access as well as during 2-h intervals of limited access to ethanol. Levels of blood ethanol were measured in both female and male HEP animals during bouts of ethanol drinking in the limited access paradigm. By the sixth generation of HEP rats, ethanol consumption of the females often exceeded that of any other rat genetically bred to drink ethanol (e.g., at a concentration of 15.7%, 10.3 g/kg per day). Seven additional characteristics are notable: 1) the HEP rats prefer ethanol in the presence of a nutritious chocolate drink or nonnutrient sweetened solution (aspartame); 2) high levels of blood ethanol are associated with their drinking; 3) females drink significantly greater g/kg amounts of ethanol than HEP males and prefer a higher percent concentration of ethanol; 4) the drinking of ethanol by the female HEP animals does not fluctuate during the estrous cycle; 5) neurochemical assays show differential profiles of 5-HT, dopamine, and their metabolites in different regions of the brain; 6) measures of activity using the elevated plus maze, open field, and cork gnawing reveal differences between genders of HEP rats and SD rats; and 7) the HEP animals are without phenotypically expressed abnormalities. Finally, one cardinal principle derived from this study revealed that the breeding strategy to develop high-ethanol-drinking rats centers on the use of multiple solutions of ethanol whereby the intakes of ethanol in concentration of 9% through 20% dictate the ultimate selection of breeding pairs over successive F generations. Further, it is concluded that because of an intense rise in ethanol drinking of the F1 generation of female HEP rats well above that of the parental SD female breeders, the complex genotypic characteristic of the male P rat is predominantly responsible for evoking ethanol drinking in female offspring.  相似文献   

6.
During a 1-hr feeding test, 34 hungry male Long-Evans rats that had been reared individually from weaning with a Swiss Webster house mouse were less likely to feed on the intact carcass of a freshly sacrificed mouse than were 39 rats that had been reared individually with another rat. Likewise, 42 hungry mice that had been reared individually with a rat were less likely to feed on a dead rat than were 29 mice that had been reared individually with another mouse. Regardless of the social conditions during rearing, hungry mice were more likely to feed on a dead mouse than were hungry rats to feed on a dead rat. Findings suggest that the tendency by rats to reject conspecific flesh stems, at least in part, from prior experience with conspecifics and with their own bodies. The experiential factors mediating the tendency by mice to reject conspecific flesh remain unclear. (35 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

7.
In a mouse model of transplacental cocaine exposure we have demonstrated alterations in brain structure and function of offspring including disturbances of brain growth, disruption of neocortical cytoarchitecture, and transient as well as persistent behavioral deficits. One mechanism by which cocaine may alter fetal brain development is through cocaine-induced alpha-adrenergic-mediated (uterine) arterial vasoconstriction. In this study pregnant Swiss Webster (SW) mice were injected with cocaine HCl (20 or 40 mg/kg, SC) without any changes evident in mean arterial blood pressure (MAP) measurements. These physiology results suggest that in our mouse model, cocaine's transplacental effects on the fetus are not due to cocaine-induced maternal vasoconstriction, nor concomitant hypoperfusion of the fetus. In a separate series of experiments, pregnant SW dams were administered cocaine HCl at 40 mg/kg/day (COC 40), 20 mg/kg/day (COC 20), or 10 mg/kg/day (COC 10) [SC, divided in two daily doses, from embryonic day (E) 8 to E17 inclusive]. Additional groups of cocaine-treated dams were administered phentolamine (5 mg/kg, SC), a short-acting alpha-adrenergic antagonist, 15 min prior to each cocaine dose (Phent COC 40, Phent COC 20, Phent COC 10). Animals born to Phent COC 40 dams demonstrated transient postnatal brain growth retardation and behavioral deficits in first-order conditioning of P9 mice comparable to mice born to COC 40 dams, which received the same regimen of cocaine injections without phentolamine pretreatment. Like COC 40 offspring, Phent COC 40 offspring also demonstrated a persistent deficit in the blocking paradigm. The behavioral and growth findings confirm and extend the physiology data, and imply that in our rodent model, alpha-adrenergic mechanisms (including maternal vasoconstriction) are unlikely to mediate these toxic effects of transplacental cocaine exposure on developing brain.  相似文献   

8.
The present study used a three-choice operant drug discrimination procedure to determine if NMDA-mediated discriminative stimulus effects could be separated from other stimulus effects of 2.0 g/kg ethanol. Adult male Long-Evans rats (n = 7) were trained to discriminate dizocilpine (0.17 mg/kg; i.g.) from ethanol (2.0 g/kg; i.g.) from water (4.7 ml; i.g.) using food reinforcement. Substitution tests were conducted following administration of the GABA(A) positive modulators allopregnanolone (5.6-30.0 mg/kg; i.p.), diazepam (0.3-10.0 mg/kg; i.p.) and pentobarbital (1.0-21.0 mg/kg; i.p.), the non-competitive NMDA antagonist phencyclidine (0.3-10.0 mg/kg; i.p.), the 5-HT1 agonists TFMPP (0.3-5.6 mg/kg; i.p.) and RU 24969 (0.3-3.0 mg/kg; i.p.), and isopropanol (0.10-1.25 g/kg; i.p.). Allopregnanolone, diazepam and pentobarbital substituted completely (>80%) for ethanol. Isopropanol partially (77%) substituted for ethanol. Phencyclidine substituted completely for dizocilpine. RU 24969 and TFMPP did not completely substitute for either training drug, although RU 24969 partially (62%) substituted for ethanol. Successful training of this three-choice discrimination indicates that the discriminative stimulus effects of 0.17 mg/kg dizocilpine were separable from those of 2.0 g/kg ethanol. The finding that attenuation of NMDA-mediated effects of ethanol occurred without altering significantly GABA(A)- and 5-HT1-mediated effects suggests that the NMDA component may be independent of other discriminative stimulus effects of 2.0 g/kg ethanol.  相似文献   

9.
10.
A 48-year-old man with an extensive history of alcoholism was found dead at home. He was lying face down on a carpet. There was evidence of gastric aspiration at autopsy and histologic examination. The distribution of ethanol was very unusual (concentrations in mg/100 mL or mg/100 g): femoral blood, 257 and 273 (two samples); heart blood, 643; vitreous humor, 763; urine, 84; bile, 616; liver, 250; and gastric, 4660 (2470 mg/53 g). In addition, this man ingested isopropanol, and, according to the history, may also have ingested acetone in the form of nail polish remover. The distribution of both isopropanol and acetone was as expected, which was approximately in proportion to the aqueous content of the respective tissues. It is proposed that agonal or postmortem aspiration of the ethanol-rich vomitus and postmortem fermentation could account for the apparently elevated concentrations of ethanol in heart blood and bile. The elevated vitreous ethanol could be explained if ethanol diffused across the eye in the agonal phase or postmortem from gastric aspirate in the carpet. The relatively low urinary ethanol concentration would be consistent with a recent binge-drinking episode, which allowed only a limited time period for excretion into an already partially full, but relatively ethanol-free, bladder.  相似文献   

11.
The effect of the 5-HT3 antagonist ondansetron on ethanol self-administration was examined in a limited access paradigm. Acute administration of ondansetron (0.01 and 0.1 mg/kg) reduced ethanol intake in male Wistar rats by 35%, whilst water intake was unaffected. Both a lower (0.001 mg/kg) and higher dose (1 mg/kg) of ondansetron failed to modify ethanol consumption. Ondansetron did not, however, alter the pharmacokinetic profile of an orally administered dose of ethanol (1 g/kg) over the same dose range. To examine the generality of these findings and to determine if tolerance would develop to the suppressant effects of ondansetron on ethanol intake, male C57BL/6 mice were treated with ondansetron (0.001, 0.01 and 0.1 mg/kg) over 22 days, 30 min prior to scheduled access to ethanol. Both 0.01 and 0.1 mg/kg doses reduced ethanol intake; however, water intake was not altered by either dose. This finding confirms and extends the generality of the effects of 5-HT3 receptor antagonists on ethanol intake across different species and different paradigms of ethanol consumption. More importantly, the present study shows that the reduction in ethanol intake induced by ondansetron was maintained even after a prolonged period of treatment and is not due to an alteration in the absorption or metabolism of ethanol.  相似文献   

12.
Patients with alcohol-induced liver disease are at increased risk for pigment gallstones, which are known to be particularly associated with biliary stasis. Although the effects of ethanol on the sphincter of Oddi are thought to contribute to alcoholic pancreatitis, the precise effects of ethanol on the biliary component of the sphincter of Oddi are unclear. In the prairie dog the common bile and pancreatic ducts enter the duodenum separately, facilitating pressure measurement in the sphincter choledochus in isolation. We therefore used this model to test the hypothesis that ethanol administration alters sphincter of Oddi motility. Twenty-six male prairie dogs fed a nonlithogenic diet were studied. With the animals under alpha-chloralose anesthesia, a side-hole pressure-monitored perfusion catheter was positioned in the sphincter of Oddi and femoral arterial and venous catheters were placed. Sphincter of Oddi phasic wave frequency (F), amplitude (A), and motility index (MI = F x A) and arterial blood pressure were monitored at 10-minute intervals before (baseline), during 20-minute intravenous infusions of 15 mg/kg (n = 9), 150 mg/kg (n = 10), and 1.5 g/kg (n = 7) ethanol and for 20 minutes after ethanol infusion. The 15 mg/kg dose of ethanol had no effect, the 150 mg/kg dose tended to reduce sphincter of Oddi motility, and significant reductions in sphincter of Oddi amplitude and motility index were seen at the 1.5 g/kg dose. These data demonstrate that ethanol infusion inhibits both sphincter of Oddi amplitude and motility index and that this effect persists for at least 20 minutes following ethanol infusion. Ethanol may contribute to gallstone formation by altering biliary sphincter motility.  相似文献   

13.
[Correction Notice: An erratum for this article was reported in Vol 120(6) of Behavioral Neuroscience (see record 2006-22387-011). In the article "Anxiogenic-Like Effect of Chronic Corticosterone in the Light-Dark Emergence Task in Mice," by Paul Ardayfio and Kwang-Soo Kim (Behaviorial Neuroscience, 2006, Vol. 120, No. 2, pp. 249-256), the measurement unit of the corticosterone concentration on p. 250 (under the Drugs heading) was incorrect. The correct unit is μg/ml. The corrected sentence follows: "Corticosterone (Sigma, St. Louis, MO) was dissolved in ethanol, diluted, and administered via the drinking water at a final concentration of 0 or 35 μg/ml in 0.3% ethanol."] Chronic hypercortisolemia is a hallmark of neuroendocrine and psychiatric disorders, such as Cushing's disease and depression. Whether cortisol directly contributes to the altered mood and anxiety symptoms seen in these diseases remains unclear. To address this, the authors have modeled hypercortisolemia by administering corticosterone in the drinking water of female Swiss Webster mice for 17 or 18 days (13 mg/kg). Light-dark emergence, startle habituation, and startle reactivity were measured. Chronic but not acute treatment with corticosterone increased the latency to emerge into the light compartment, an anxiogenic-like effect. Chronic corticosterone treatment did not affect startle habituation, but did reduce startle reactivity. This study suggests that chronic hypercortisolemia may contribute to anxiety-related behavior in patients with Cushing's disease and depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

14.
Twelve paid student volunteers (8 male, 4 female) were used in a double-blind crossover experiment to investigate the effects of delta9-tetrahydrocannabinol (THC) alone, and in combination with ethanol, on human perceptual, cognitive and motor functions. Both THC (10 mg/70 kg) and ethanol (0-5 g/kg) had little effect when administered alone. The combination of drugs, however, induced a significnat decrement in performance in some of the tests and this interaction was considered to be at least additive. The peak blood ethanol concentration was higher (P = 0-05) when subjects received both ethanol and THC than when they received ethanol alone.  相似文献   

15.
The aim of the present study was to investigate whether ethanol training affects the ability of Ro 15-4513 to block the discriminative stimulus effects of ethanol dose differentially. Three different groups of rats were trained to discriminate 1.0 g/kg ethanol (n = 8), 1.5 g/kg ethanol (n = 7) or 2.0 g/kg ethanol (n = 8) from water in a two-lever, food-reinforced procedure. Ethanol and water were administered by gavage 20 min before the onset of the session. When the discrimination performance was stable, rats were pretreated with Ro 15-4513 (1-17 mg/kg; i.p.) 5 min before the administration of ethanol. Ro 15-4513 attenuated the discriminative stimulus effects of 1.0 and 1.5 g/kg ethanol but not 2.0 g/kg ethanol in each of the ethanol training groups. Overall, blockade of the discriminative stimulus effects of 1.0 and 1.5 g/kg ethanol by 5.6 mg/kg Ro 15-4513 occurred without significantly altering response rates or blood ethanol concentrations. A decrease in blood ethanol concentration was, however, found with 17 mg/kg Ro 15-4513 in combination with 2.0 g/kg ethanol. These results suggest that the benzodiazepine partial inverse agonist, Ro 15-4513, can attenuate the discriminative stimulus effects associated with low to moderate doses of ethanol (1.0-1.5 g/kg).  相似文献   

16.
The sedative and anesthetic effects of ethanol and propofol when these drugs are coadministered are not known. Accordingly, we investigated the nature of the pharmacological interaction between ethanol and propofol during hypnosis and anesthesia in the mouse. Propofol, ethanol, and mixtures of the two were administered through the tail vein in male CD-1 mice (n = 162). The loss of righting response occurring 10 s after injection and persisting at least 10 s thereafter was defined as hypnosis, and lack of a motor response to tail clamping 60 s after injection was defined as anesthesia. The 50% effective dose (ED50) values for the hypnotic and anesthetic actions of the drugs were determined with quantal dose-response curves, using probit analysis. The pharmacological interactions were identified by the locations of ED50 values on their corresponding hypnosis and anesthesia isoboles. For each drug alone, the hypnotic and anesthetic ED50 values with 0.95 confidence intervals were 16.70 (11.98, 23.20) mg/kg and 25.02 (20.27, 31.29) mg/kg for propofol and 0.88 (0.81, 0.95) g/kg and 1.80 (1.45, 2.23) g/kg for ethanol, respectively. For the drugs in combination, the ED50 values for hypnosis with 0.95 confidence intervals were 6.98 (6.50, 7.49) mg/kg propofol with 0.61 (0.57, 0.66) g/kg ethanol, and for anesthesia were 10.55 (9.76, 11.42) mg/kg propofol with 0.93 (0.86, 1.05) g/kg ethanol, respectively. When plotted isobolographically, we found these combinations to be behaviorally additive both for hypnosis and anesthesia. Although a finding of synergism would have excluded the possibility of an identical mechanism of action for the drugs, elucidation of the molecular basis of the additivity must await further studies.  相似文献   

17.
Subcutaneous injection of epidermal growth factor 1. significantly shortened the latency period for the appearance of methylcholanthrene induced skin tumors and 2. increased the average number of papillomas elicited per mouse in both the Swiss Webster and C3HeB/FeJ strains.  相似文献   

18.
Previous drug discrimination studies have elucidated the importance of gamma-aminobutyric acidA (GABAA), N-methyl-D-aspartate (NMDA) glutamate, and serotonin (5-HT) receptor systems in mediating the discriminative stimulus effects of ethanol. The present study used a three-choice operant drug discrimination procedure in an attempt to determine if salient GABAergic effects could be separated from other stimulus effects of 2.0 g/kg ethanol. Adult male Long-Evans rats (n = 7) were trained to discriminate pentobarbital (10.0 mg/kg; intragastrically (i.g.) from ethanol (2.0 g/kg; i.g.) from water (4.7 ml; i.g.) using food reinforcement. Stimulus substitution tests were conducted following the administration of allopregnanolone (1.0-17.0 mg/kg; intraperitoneally (i.p.)), diazepam (0.1-7.3 mg/kg; i.p.), midazolam (0.0056-17.0 mg/kg; i.p.), dizocilpine (0.01-0.56 mg/kg; i.p.), phencyclidine (1.0-5.6 mg/kg; i.p.), CGS 12066B (3-30 mg/kg; i.p.), RU 24969 (0.1-5.6 mg/kg; i.p.) and morphine (1 or 3.0 mg/kg; i.p.). Within the group, allopregnanolone and midazolam completely substituted (> 80%), and diazepam partly substituted (67%) for the discriminative stimulus effects of pentobarbital. Dizocilpine and phencyclidine partly substituted (58 and 57%, respectively) for ethanol without substantial pentobarbital-appropriate responding. RU 24969, CGS 12066B and morphine did not result in complete substitution for either ethanol or pentobarbital, although RU 24969 resulted in partial (68%) pentobarbital substitution. The ability to train the present three-choice discrimination in rats indicates that the discriminative stimulus effects of 10.0 mg/kg pentobarbital were separable from those of 2.0 g/kg ethanol. The results suggest that the pharmacological effects of ethanol, which can control behavior, may seemingly be modified by training conditions (two-versus three-choice discrimination procedures), to the extent that a receptor system prominently linked to the behavioral activity of ethanol (i.e. GABAA) appears no longer to be involved in the interoceptive effects of the drug.  相似文献   

19.
Mammalian alcohol dehydrogenases ADH1 (class I ADH) and ADH4 (class IV ADH) function as retinol dehydrogenases contributing to the synthesis of retinoic acid, the active form of vitamin A involved in growth and development. Xenopus laevis ADH1 and ADH4 genes were isolated using polymerase chain reaction primers corresponding to conserved motifs of vertebrate ADHs. The predicted amino acid sequence of Xenopus ADH1 was clearly found to be an ortholog of ADH1 from the related amphibian Rana perezi. Phylogenetic tree analysis of the Xenopus ADH4 sequence suggested this enzyme is likely to be an ADH4 ortholog, and this classification was more confidently made when based also on the unique expression patterns of Xenopus ADH1 and ADH4 in several retinoid-responsive epithelial tissues. Northern blot analysis of Xenopus adult tissues indicated nonoverlapping patterns of ADH expression, with ADH1 mRNA found in small intestine, large intestine, liver, and mesonephros and ADH4 mRNA found in esophagus, stomach, and skin. These nonoverlapping tissue-specific patterns are identical to those previously observed for mouse ADH1 and ADH4, thus providing further evidence that Xenopus ADH1 and ADH4 are orthologs of mouse ADH1 and ADH4, respectively. During Xenopus embryonic development ADH1 mRNA was first detectable by Northern blot analysis at stage 35, whereas ADH4 mRNA was undetectable through stage 47. Whole-mount in situ hybridization indicated that ADH1 expression was first localized in the pronephros during Xenopus embryogenesis, thus conserved with mouse embryonic ADH1 which is first expressed in the mesonephros. ADH4 expression was not detected in Xenopus embryos by whole-mount in situ hybridization but was localized to the gastric mucosa of the adult stomach, a property shared by mouse ADH4. Conserved expression of ADH1 and ADH4 in retinoid-responsive epithelial tissues of amphibians and mammals argue that these enzymes may perform essential retinoid signaling functions during development of the pronephros, mesonephros, liver, and lower digestive tract in the case of ADH1 and in the skin and upper digestive tract in the case of ADH4.  相似文献   

20.
Reports an error in "Anxiogenic-Like Effect of Chronic Corticosterone in the Light-Dark Emergence Task in Mice" by Paul Ardayfio and Kwang-Soo Kim (Behavioral Neuroscience, 2006[Apr], Vol 120[2], 249-256). In the article "Anxiogenic-Like Effect of Chronic Corticosterone in the Light-Dark Emergence Task in Mice," by Paul Ardayfio and Kwang-Soo Kim (Behaviorial Neuroscience, 2006, Vol. 120, No. 2, pp. 249-256), the measurement unit of the corticosterone concentration on p. 250 (under the Drugs heading) was incorrect. The correct unit is μg/ml. The corrected sentence follows: "Corticosterone (Sigma, St. Louis, MO) was dissolved in ethanol, diluted, and administered via the drinking water at a final concentration of 0 or 35 μg/ml in 0.3% ethanol." (The following abstract of the original article appeared in record 2006-05348-003.) Chronic hypercortisolemia is a hallmark of neuroendocrine and psychiatric disorders, such as Cushing's disease and depression. Whether cortisol directly contributes to the altered mood and anxiety symptoms seen in these diseases remains unclear. To address this, the authors have modeled hypercortisolemia by administering corticosterone in the drinking water of female Swiss Webster mice for 17 or 18 days (13 mg/kg). Light-dark emergence, startle habituation, and startle reactivity were measured. Chronic but not acute treatment with corticosterone increased the latency to emerge into the light compartment, an anxiogenic-like effect. Chronic corticosterone treatment did not affect startle habituation, but did reduce startle reactivity. This study suggests that chronic hypercortisolemia may contribute to anxiety-related behavior in patients with Cushing's disease and depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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