摘要:

Investigations of ethanol's (EtOH's) complex response profile, including locomotor and other effects, are likely to lead to a more in‐depth understanding of the constituents of alcohol addiction. Locomotor activity responses to acute and repeated EtOH (2 g/kg, ip) exposures were measured in BXD recombinant inbred (RI) mice and their C57BL/6J (B6) and DBA/2J (D2) progenitors. Both the acute response and the change in initial EtOH response with repeated treatments were strain‐dependent. The coefficient of genetic determination was 0.38–0.49 for initial locomotor response to EtOH, and 0.29 for change in response. Changes in response were largely attributable to sensitization of locomotor stimulation. Quantitative trait loci (QTL) analyses identified significant marker associations with basal activity, acute locomotor response, and change in response. Markers were for QTL on several chromosomes, and there was only one case of overlap in marker associations among phenotypes. Acute locomotor response and locomotor sensitization were negatively correlated with 3% EtOH preference drinking data collected in BXD Rl strains. Overall, these results demonstrate locomotor sensitization induced by EtOH, suggest independence of genetic determination of locomotor responses to acute and repeated EtOH exposure, and partially support a relationship between reduced sensitivity to the locomotor stimulant/sensitizing effects of EtOH and EtOH consum

ISSN:0145-6008    

DOI:10.1111/j.1530-0277.1995.tb01502.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

High alcohol drinking (HAD) and low alcohol drinking (LAD) rats were tested, in three exposures, for taste reactivity to five concentrations of alcohol (5%, 10%, 20%, 30%, and 40%, v/v), water, and one concentration each of sucrose and quinine. Of the three reactivity exposures, one was done before a 3‐week period of continuous access to water and 10% alcohol, the second test was done immediately after the consumption period, and the final reactivity test was done after 1 month of alcohol abstinence. The results showed that the groups did not differ in reactivity on the initial test. After the consumption tests (when the HAD rats consumed significantly more alcohol than the LAD rats), differences in reactivity were found: HAD rats produced significantly more ingestive responses (which promote consumption) and significantly fewer aversive responses (which facilitate fluid rejection) than LAD rats. These differences were maintained even after 1 month of alcohol abstinence. The present data replicate an earlier experiment with alcohol‐preferring (P) rats and alcohol‐non‐preferring (NP) rats, and indicate that the selective breeding process does not produce differences in the innate perception of the taste of alcohol. However, after experience with drinking alcohol, rats selectively bred for high alcohol consumption exhibit a palatability shift reflected by high ingestive responding and little or no aversive responding. Such a shift would clearly contribute to the maintenance of high levels of alcohol cons

ISSN:0145-6008    

DOI:10.1111/j.1530-0277.1995.tb01503.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Chronic alcohol intoxication has been associated with increased migration of inflammatory leukocytes to the liver that may contribute to the development of alcoholic hepatitis in susceptible individuals. Thus, this work was performed to examine the mechanism by which neutrophils [polymorphonuclear neutrophils (PMNs)] are sequestered in the liver during prolonged consumption of alcohol. Male Sprague‐Dawley rats were fed with Sustacal supplemented by 36% alcohol, or isocaloric diet for 16 weeks. Circulating blood PMNs were collected and examined for CD18 (β2‐integrin) adhesion molecule expression. Monoclonal antibody 1F12, an anti‐CD18 antibody and potent neutropenic agent, was used to detect CD18 on PMNs. More than 97% of neutrophils obtained from pair and ethanol‐fed rats were positive for the antibody. Fluorescence intensity of fluorescein iso‐thiocyanate‐1F12 binding to PMNs from ethanol‐fed rat was significantly enhanced 2‐fold compared with the pair‐fed controls. The release of chemoattractant and free radical‐generating activity in culture supernatants of Kupffer cells was also examined. Twenty‐four hr culture supernatants of Kupffer cells from chronic alcoholic rats enhanced the migration and superoxide anion generation by normal PMNs, compared with those of the pair‐fed rats. Antirat interleukin‐8 antiserum inhibited chemotactic activity and superoxide generating capacity of culture supernatants. These results suggest that upregulation of adhesion molecules on PMNs and chemotactic factor release from Kupffer cells may contribute, at least in part, to enhanced migration of inflammatory leukocytes to the liver during ch

ISSN:0145-6008    

DOI:10.1111/j.1530-0277.1995.tb01504.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Transmission and scanning electron microscopic studies were performed on the liver sinusoid, with emphasis on sinusoidal endothelial cells, in rats fed a liquid diet containing either alcohol or dextrin (control) for 14 weeks. Animals were also treated with either Gram‐negative bacterial lipopolysaccharide (LPS; 100 μg/100 g body weight, intravenously) or sterile saline (control). All specimens were prepared after perfusion fixation of the liver. Livers of rats fed dextrin‐containing liquid diet displayed the ultrastructural features typical of the sinusoid and its endothelial cells. Livers from alcohol‐fed animals, however, were characterized by massive loss of sieve‐plate architecture of the sinusosidal endothelium, which was virtually replaced with a meshwork of enlarged openings with diameters frequently exceeding 1 urn. Morphological evidence of Kupffer cell activation could also be seen along with significant fatty infiltration of the hepatocyte. Conversely, LPS administration to dextrin‐fed animals induced an apparent decrease in fenestration of the sinusoidal endothelial cell, accompanied by morphological evidence of enhanced endocytotic activity and cytoplasmic swelling. The changes seen 3 hr after LPS administration were markedly advanced at 24 hr. LPS administration to alcohol‐fed rats accentuated the alterations observed after alcohol treatment alone. Additionally, the presence of platelets in the sinusoid as well as adhering to the hepatocyte microvilli in the space of Disse, along with the presence of Ito and Kupffer cell activation, greater than that observed in the alcohol‐treated rats, is morphological evidence consistent with the disruption of vascular integrity in the liver. Interestingly, LPS treatment did not reverse the effects of alcohol on the sinusoidal endothelial cell fenestration. The possible functional consequences of alcohol‐ and LPS‐induced ultrastructural alterations of the sinusoidal endothelial cell, and of the hepatic sinusoid in general, are evaluated in light of the available data on scavenging function of the sinusoida

ISSN:0145-6008    

DOI:10.1111/j.1530-0277.1995.tb01505.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

We present a repeated‐measures analysis of ethanol‐induced loss of righting reflex (LRR) in Inbred Long‐Sleep (ILS) and Inbred Short‐Sleep (ISS) strains of mice and their F1and F2cross progeny. Mice were administered a 4.1 g/kg intraperitoneal dose of ethanol at two times, 7–10 days apart. Repeatability is nonsignificant in ILS, ISS, and F, mice, but is highly significant (0.47,p<0.01) in the F2mice. Mean LRR does not differ between trials 1 and 2, with the exception of the ISS strain in which the interaction of sex with LRR sensitization is significant. This two‐trial method leads to increased accuracy of genotype assessment for pharmacological or behavioral traits where trial 1 does not influence the outcome of trial 2. The repeated‐measures design facilitates novel analyses of the duration of LRR, and results suggest that most environmental variance for LRR is due to nonreplicab

ISSN:0145-6008    

DOI:10.1111/j.1530-0277.1995.tb01506.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

We investigated the effect of ethanol on specific binding of [3H]MK‐801 to the intrachannel phencyclidine (PCP) receptor site, as an index of change in the functional response of theN‐methyl‐d‐Aspartate (NMDA)‐associated ion channel. Saturation binding experiments were performed on synaptic membrane homogenates from adult rat cortex and hippocampus. [3H]MK‐801 binding assays were conducted under conditions of basal, 10 μm glutamate, or 10 μm glutamate + 30 μmd‐serine, with and without 50 or 100 mm ethanol. Association experiments of [3H]MK‐801 binding (5 nm) were conducted under conditions of 0 or 10 μmglutamate, with varying concentrations of glycine (0.01, 0.10, and 10 μm) with and without 100 mmethanol. Ethanol (50 and 100 mm) significantly decreased the percentage of high‐affinity (open‐channel state) MK‐801 receptors with a concomitant increase in percentage of low‐affinity receptors, but did not change high‐ and low‐affinity constants of the two binding states. An ethanol‐induced increase in the closed‐channel receptor density in basal and activated conditions was suggested by the saturation experiments. Association experiments further explained this finding, in that ethanol (100 mm) significantly decreased fast component (open‐channel) [3H]MK‐801 binding in conditions of glycine (0.01–10 μm) only and activated conditions of glutamate + glycine (0.01–0.10 μm). However, the observed fast and slow kinetic rate constants of [3H]MK‐801 binding, as well as total specific binding (fast + slow components), were not altered. Thus, ethanol seems to act as a noncompetitive antagonist upon the gating mechanism of, and ligand access to, the NMDA‐coupled ion channel. These findings support previous observations of ethanol selectively reducing NMDA‐activated calcium influx, and reducing the frequency and duration of ion channel opening in electrophysiological studies. Similar to previous reports on NMDA‐stimulated calcium influx and [3H]MK‐801 binding, glycine (at the maximal concentration of 10 μm), in the presence of 10 μmglutamate, was fou

ISSN:0145-6008    

DOI:10.1111/j.1530-0277.1995.tb01507.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Acetaldehyde can form protein‐acetaldehyde adducts (AAs) in vivo and may play a role in the genesis of alcoholic liver disease. The nature of the chemical modification of proteins by acetaldehyde in vivo has not been elucidated. In vitro, acetaldehyde can form reversible adducts including a Schiff's base with lysine (K) and imidazolidinone with terminal amino groups of proteins such as human hemoglobin (Hb). In this study, we used FAB/MS to analyze the products of peptide‐AAs (pep‐AAs) formed by incubating acetaldehyde with Hb peptides. We then used an octabranched multiple antigen peptide (MAP) system containing Hb peptide‐AAs to raise antibodies. Three Hb peptides [i.e., 8‐pep consisting of 8 residues (V1HLTPVEK8) at the N‐terminus ofβ‐chain of human sickle‐cell Hb, 11‐pep‐gly consisting of 11 residues (G56NPKVKAHGKK66) in a segment ofβ‐chain rich in lysine, and 11‐pep‐pro that consists of the same sequence as 11‐pep‐gly, except G56was replaced by proline (P)] were incubated with 1 mM acetaldehyde at 4°C for 7d without NaCNBH3(nonreduced conditions). Analysis by FAB/MS showed that 8‐pep formed an imidazolidinone at the N‐terminal valine, 11‐pep‐gly formed a Schiff's base and imidazolidinone at the N‐terminus, whereas 11‐pep‐pro that lacks a free α‐amino group formed only a Schiff's base at K59. By contrast, incubation of these Hb peptides with 250 mM acetaldehyde and NaCNBH3at 37°C for 1 hr (reduced conditions) produced mono‐and diethylated modifications of all available K residues, as well as the N‐terminal amino group. MAP‐11‐pep‐gly and MAP‐11‐pep‐pro were prepared and reacted with 1 mM acetaldehyde under nonreduced conditions. Antibodies against these nonreduced MAP‐11 ‐pep‐AAs were raised. By ELISA assay, antibodies against nonreduced MAP‐11‐pep showed reactivity with Hb‐AA prepared under nonreduced conditions. Unexpectedly, these antibodies also reacted with Hb‐AA prepared under reduced conditions as well. Our studies therefore showed: (1) acetaldehyde can modify peptides with or without NaCNBH3producing different chemical modifications; (2) lysine residues, although located in close vicinity in a peptide, are not equally reactive in forming a stable AA; and (3) antibodies raised by nonreduced MAP

ISSN:0145-6008    

DOI:10.1111/j.1530-0277.1995.tb01508.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Pharmacologically isolated, NMDA receptor‐mediated population EPSPs (pEPSPs) were evoked from area CA1 of hippocampal slices using electrical stimulation of the Schaffer collateral/commissural fiber pathway. Slices were prepared from rats aged 20–25 or 80–100 days. The inhibitory effects of a range of ethanol concentrations were assessed. While ethanol antagonized NMDA‐mediated pEPSPs in slices from both age groups, it was significantly more potent against pEPSPs from immature versus mature hippocampi. In slices from mature animals, significant and consistent reduction of pEPSPs was observed only with the highest ethanol concentration (100 mm), whereas 10, 30, or 100 mmsignificantly reduced the amplitude of pEPSPs in slices from immature animals. These results indicate that NMDA‐mediated synaptic activity in the hippocampus is more sensitive to the effects of ethanol in immature versus matur

ISSN:0145-6008    

DOI:10.1111/j.1530-0277.1995.tb01509.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

The effects of ethanol (EtOH) consumption by adult female C57BI/6 mice on lymphocyte populations of the mesenteric lymph nodes (MLNs) were determined by feeding mice with the Lieber‐DeCarli liquid diet by a pair‐feeding paradigm. Histological analysis of the MLNs of EtOH‐fed mice showed a progressive loss of lymphocytes from the medullary regions at 3, 5, and 7 days after initiation of the EtOH diet. The stromal cells in the medullary region also demonstrated a progressive alteration in stellate morphological features at times corresponding to those of loss of lymphocytes from this region. Microscopic evaluation of the follicle regions of MLNs obtained from mice fed an EtOH‐containing diet showed no appreciable alterations in morphological characteristics. The number of tingible body macrophages in the germinal centers of the follicles, however, was increased after 3 days of EtOH diet feeding and declined progressively after this time. Flow cytometric analysis of isolated lymphocytes showed a depletion of both T and B cell populations from the MLNs. In contrast to B cells, however, T cells were depleted through 7 days of EtOH diet feeding. Total RNA isolated from the MLNs of mice consuming the EtOH‐containing diet was progressively degraded. No degradation of DNA was observed. These study results establish that continuous consumption of dietary EtOH adversely affects the cellularity of MLN, resulting in a progressive loss of lymphocytes that is associated with degradation of

ISSN:0145-6008    

DOI:10.1111/j.1530-0277.1995.tb01510.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Tumor necrosis factor‐α (TNF‐α) has been shown to contribute to the alcohol [ethanol (ETOH)]‐induced alteration of hepatic function. Therefore we tested the hypothesis that the hepatic action of TNF‐α could be due, at least in part, to alterations in TNF‐α cell‐surface receptors of hepatic parenchymal (hepatocytes) and nonparenchymal (Kupffer and sinusoidal endothelial) cells. Rats were either acutely treated with ETOH by a primed, continuous 7‐hr intravenous infusion of 20% (w/v) ETOH (30 mg/100 g body weight/h) or chronically fed an ETOH‐containing liquid diet (5.2% ETOH, w/v, with ETOH as 36% of total calories) for 14 weeks. Control rats in the acute group were infused with sterile saline, whereas control rats in the chronic group were fed liquid diet containing dextrin to replace ETOH in isocaloric amounts. Three hr before killing, the rats were injected intravenously with Gram‐negative bacterial lipopolysaccharide [(LPS) 100 /μg/100 g body weight]or saline. Hepatocytes, Kupffer cells, and sinusoidal endothelial cells were isolated after liver perfusion with collagenase (without pronase), separated by centrifugal elutriation, and used to determine the affinity (Kd) and capacity (Bmax) of binding sites, using recombinant human‐[125l]TNF‐α as the ligand. Two binding sites were detected on Kupffer cells and sinusoidal endothelial cells isolated from control animals: a high‐affinity (Kd1, in the range of 150–200 PM), low‐capacity (Bmax1, in the range of 2–3 fmol/106cells) binding site and a low‐affinity (Kd2, in the range of 2–9 nm), high‐capacity (Bmax2, in the range of 3–15 fmol/106cells) binding site. One binding site was detected on hepatocytes isolated from control rats (Kd1= 1.0 nm and aBmax= 95 fmol/106cells). Acute ETOH administration caused an increase inKd1on both Kupffer and sinusoidal endothelial cells; a decrease inKd1onhepatocytes; andanincrease inKd2, Bmax1, and Bmax2on endothelial cells. A second binding site on hepatocytes (Kd2= 5.8 nm, Smax2= 186 fmol/106cells) was observed only in the ETOH‐treated group after LPS administration. Chronic alcohol exposure markedly elevatedKd1and Smax1on hepatocytes. Overall, LPS‐induced changes mimicked those induced by alcohol, except for a decrease in Bmax1on Kupffer cells of rats in the acute treatment group. Also, the liquid diet containing alcohol or dextrin abrogated the high‐affinity, low‐capacity binding sites on both Kupffer cells and sinusoidal endothelial cells, and low‐affinity, high‐capacity binding sites on the hepatocyte. After LPS administration, the high‐affinity binding sites on Kupffer and sinusoidal endothelial cells were reexpressed. These data show that: (1) ETOH induces changes in both the capacity (Bmax) and affinity (Kd) of TNF‐α cell‐surface receptors of hepatocytes, Kupffer cells, and sinusoidal endothelial cells; and (2) ETOH‐induced changes are consistent wit

ISSN:0145-6008    

DOI:10.1111/j.1530-0277.1995.tb01511.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY