Chronic alcohol muscle disease is characterized by reduced skeletal muscle mass precipitated by acute reduction in protein synthesis. The pathogenic mechanisms remain obscure, but several lines of evidence suggest that increased oxidative stress occurs in muscle in response to alcohol and this may be associated with impaired α-tocopherol status. Potentially, this implies a therapeutic role for α-tocopherol, especially as we have shown that supplemental α-tocopherol may increase the rate of protein synthesis in normal rats [Reilly, Patel, Peters and Preedy (2000) J. Nutr. 130 , 3045–3049]. We investigated the therapeutic effect of α-tocopherol on plantaris muscle protein synthesis in rats treated either acutely, chronically or chronically+acutely with ethanol. Protein synthesis rates were measured with a flooding dose of L -[4- 3 H]phenylalanine. Protein, RNA and DNA contents were determined by standard laboratory methods. Ethanol caused defined metabolic changes in muscle, including decreased protein, RNA and DNA contents in chronically treated rats. In acute or chronic+acute studies, ethanol suppressed fractional rates of protein synthesis. α-Tocopherol supplementation did not ameliorate the effects of either acute, chronic or chronic+acute alcohol on plantaris muscle protein content or rates of protein synthesis. In control animals (not treated with alcohol), α-tocopherol supplementation decreased muscle protein content owing to increases in protein turnover (both synthesis and degradation). α-Tocopherol supplementation is not protective against the deleterious effects of alcohol on protein metabolism in skeletal muscle.

1. The time course of iron overload of the pancreas in hypotransferrinaemic mice maintained on a standard rodent diet was compared with biochemical and histological markers of tissue damage. 2. Pancreatic iron levels increased linearly from weaning till 9 months of age [73.3 nmol/mg of tissue (SEM 9.9; n = 5) compared with 0.9 nmol/mg of tissue (SEM 0.1; n = 4) in age-matched controls] then decreased linearly till at least 18 months of age. 3. Investigation of tissue distribution of newly absorbed radioiron suggested that significant redistribution of iron from liver to pancreas (rather than direct dietary iron sources) must be invoked to explain the rate of pancreatic iron loading in hypotransferrinaemic mice. 4. Pancreatic epithelial cells first showed altered morphology at 9 months of age. At 12 months of age, the pancreatic epithelium had developed a micronodular appearance, with large numbers of acini replaced by atrophic, degenerated acinar cells. Increased collagen fibre deposition was evident by trichrome staining and by electron microscopy. Biochemical markers of pancreatitis (serum lipase, tissue pancreatitis-associated protein mRNA) were elevated before 9 months of age, whereas the levels of pancreatic amylase mRNA declined from 9 months of age. 5. The data suggest that iron loading of hypotransferrinaemic mouse pancreas proceeds up to a threshold level at 9 months of age followed by a progressive atrophy of secretory epithelium. The hypotransferrinaemic mouse pancreas is a useful model system for investigation of parenchymal cell damage by iron.

1. In the present study we have examined the expression of pancreatitis-associated protein mRNA in mouse pancreas and small intestine and determined the effect of a number of factors on the steady-state level of the RNA. 2. The normally low level of pancreatitis-associated protein mRNA in pancreas increased severalfold after 6 h of hypoxia, reaching peak levels (approximately 10-fold greater than normal) after 24 h hypoxia. After 3 days' hypoxia pancreatitis-associated protein mRNA levels were again undetectable. 3. In the pancreas the level of pancreatitis-associated protein mRNA was also increased by alcohol and iron overload, but not by paracetamol. 4. In the small intestine expression of pancreatitis-associated protein mRNA was higher in normal ileum than in duodenum. In the ileum pancreatitis-associated protein mRNA levels were increased 7 to 15-fold after 6 h hypoxia, reaching peak levels by 24 h. Levels declined after 3 days' hypoxia, but remained higher than normal. 5. In the ileum long-term (4 weeks) dietary iron deficiency reduced pancreatitis-associated protein mRNA levels compared with control fed mice, whereas parenteral iron overload increased pancreatitis-associated protein mRNA levels. 6. The data presented suggest regulation of pancreatitis-associated protein gene expression by both oxygen tension and iron status.

1. Cyclosporin A absorption was examined after the instillation of approximately 2 mg/kg into four segments (mean length 15 cm) of rat small bowel, isolated in situ in fed Wistar female rats: SI (duodenum and proximal jejunum distal to the common bile duct); SII (distal jejunum); SIII (proximal ileum) and SIV (distal ileum). 2. Cyclosporin A concentrations in whole blood were assayed by an enzyme-mediated immunoassay for up to 4 h in samples drawn from the femoral vein and used to determine the following pharmacokinetic parameters: the area under the blood cyclosporin A concentration versus time curve (AUC, 0–4 h), the maximum blood concentration of cyclosporin A ( C max. ), the time to reach C max . ( t max. ), the absorption half-life ( t 1/2a ), the elimination half-life ( t 1/2λ ), and the mean residence time (MRT). 3. Cyclosporin A absorption in SI (AUC, 991 μ l −1 h) was nearly double that in more distal segments and decreased progressively (SII, 533 μg l −1 h; SIII, 470 μg l −1 h; SIV, 419 μg l −1 h). There were corresponding differences in C max : 327 μg/l in SI and 201 μg/l, 169 μg/l and 151 μg/l in SII, SIII and SIV, respectively. T max. was shorter in SIV (0.9 h) than in other segments (1.3-1.5 h), but there were no significant differences between the segments for t 1/2a , t 1/2λ or MRT. 4. In the presence of continuous bile flow (diverted via a cannula for SIV), cyclosporin A absorption significantly increased by 23% in SI and by 50% in SIV, but the differential between absorption in SI and SIV was maintained. 5. We conclude that cyclosporin A is absorbed throughout the rat small intestine with the greatest absorption rate in the proximal duodenum and jejunum, and that bile significantly augments cyclosporin A absorption in both the proximal and particularly the distal small bowel.

1. The metabolic consequences of chronic ethanol feeding was investigated by assay of urinary metabolites. Male Wistar rats were fed a liquid diet containing 35% of total energy as ethanol or isovolumetric, isocaloric and isonitrogenous amounts of the same diet in which ethanol was substituted by isocaloric glucose (controls). 2. At 6 weeks the entire skeletal muscle mass was reduced by approximately 20%. The urinary excretion of nitrogen, urea and uric acid increased by between 23 and 128%. Urinary creatinine excretion was not significantly altered. 3. Urinary excretion of magnesium was significantly increased by 43%. Urinary excretion of sodium, potassium, calcium and phosphate was increased slightly (i.e. 5–22%), but this change was not statistically significant. 4. Proton n.m.r. spectroscopic analysis showed that ethanol feeding reduced the urinary excretion of citrate and 2-oxoglutarate (by approximately 50%), suggesting decreased citric acid cycle activity. There was an increased excretion of alanine (44%), but excretion of succinate and acetate was not significantly altered. Ethanol in the urine of ethanol-fed rats comprised approximately 2% of total ethanol intake and less than 1% of total energy intake. 5. Lactose was detectable in urine of ethanol-fed rats, but not in control rats, reflecting the reported decreased intestinal lactase activity and increased gut permeability in alcoholics. Urinary galactose excretion decreased by 41%, but relatively large increases in lactate excretion (50%) did not achieve statistical significance. 6. It was concluded that chronic ethanol feeding causes disturbances in whole-body nitrogen homoeostasis and alterations in intermediary metabolism.

1. Patients with a history of alcohol abuse were studied by 31 P n.m.r. spectroscopy of the liver in vivo , and the results were related to the pattern of disease assessed by standard biochemical and histological techniques. 2. The ratios of metabolites measured from the 31 P n.m.r. spectra were abnormal in patients with alcoholic hepatatis but not in those with fatty change or cirrhosis in the absence of hepatitis. In particular, the levels of phosphomonoesters were raised, with respect either to P i , or to adenosine 5′-triphosphate. The level of phosphomonoesters showed a significant positive correlation with the severity of alcoholic hepatitis, assessed by histology. 3. The ratio of P i to adenosine 5′-triphosphate was used as a measure of the energy status of the hepatocytes, and was unchanged between patients and controls.

1. The effects of a single dose of ethanol (75 mmol/kg body weight) on rates of muscle protein synthesis were examined in young rats. Fractional rates of protein synthesis were measured in the soleus, plantaris, gastrocnemius, diaphragm and stomach by the large ‘flooding-dose’ technique. 2. After 150 min, the fractional synthesis rates of all muscles were reduced by 15–35%. Skeletal muscles containing a predominance of anaerobic (fast-twitch, type II) fibres showed greater changes when compared with skeletal muscles with a predominance of aerobic (slow-twitch, type I) fibres. 3. Gastrocnemius muscles were separated into sarcoplasmic, stromal and myofibrillar protein fractions. Protein synthesis was reduced similarly in all fractions by ethanol treatment, by approximately 30%. 4. As skeletal muscle mass comprises 40% of body weight, the responses have important physiological implications and may also be responsible for the muscle atrophy observed in alcoholic patients.

1. Percutaneous liver biopsy specimens were obtained from 11 control subjects, 24 alcoholic patients and six diabetic patients with mild to severe fatty liver and incubated in Krebs–Henseleit buffer containing 3 H 2 O. The incorporation of 3 H into fatty acid was measured and the absolute rate of fatty acid synthesis calculated. 2. Fatty acid synthesis rates were significantly lower in alcoholic fatty liver than in controls. 3. Fatty acid synthesis rates were similar in controls and patients with diabetic fatty livers. 4. Addition of 50 mmol/l ethanol did not alter the fatty acid synthesis rates in vitro. It is concluded that enhanced lipogenesis is not the major cause of fatty liver in patients with alcoholic fatty liver.

1. Human hepatic lipase activities were studied in needle biopsy specimens by fluorogenic and radioisotopic assay methods. Using analytical subcellular fractionation by sucrose density gradient centrifugation a lysosomal acid lipase, with pH optimum of 4.0, and an endoplasmic reticulum alkaline lipase, with pH optimum of 8.5, were demonstrated with the fluorogenic assay. 2. The apparent K m of the acid lipase was 17 μmol/l by the fluorogenic method and 23 mmol/l by the radioisotopic method. The values for alkaline lipase were 94 μmol/l and 1.4 mmol/l respectively. 3. Assay of these activities in biopsies from 16 control subjects and 42 chronic alcoholics showed increasing activity with increasing hepatic fatty infiltration when the fluorogenic assay was used: no differences were demonstrated with radioisotopic assay. These results suggest that depressed lipolysis due to a relative deficiency of triglyceride lipase is not a causal factor in triglyceride accumulation in chronic alcoholic fatty liver.

1. Muscle protein breakdown in vivo has been studied by measurements of urinary 3-methylhistidine/creatinine ratios. No differences were found between control subjects and chronic alcoholics either with or without proximal muscle wasting or cirrhosis. 2. Calculation of muscle turnover rates, with the correction of Afting et al. (1981, Biochemical Journal , 200, 449-452) for non-skeletal muscle contributions of 3-methylhistidine and creatinine, showed lower values for alcoholics compared with controls. 3. Tissue activities of a neutral protease, assayed by a novel, rapid and sensitive fluorimetric method, were similar in patients and controls. The activity did not vary with severity of atrophy or the presence of cirrhosis. 4. No evidence was therefore obtained to suggest that alcoholic myopathy is due to increased muscle breakdown.

1. Duodenal mucosa was collected from control rats and from animals which had received cysteamine, cysteamine plus cimetidine or pentagastrin. Animals which received cysteamine with or without cimetidine developed acute duodenal ulcers. Cysteamine treatment resulted in gastric acid hypersecretion, which was largely abolished by concurrent cimetidine administration. 2. Activities of enzymes implicated in bicarbonate secretion, HCO − 3 -activated ATPase, carbonic anhydrase and Na + + K + -activated ATPase, were measured in the duodenal mucosa of control rats and animals 24 h after subcutaneous administration of cysteamine. Assays of these enzymes in duodenal mucosal homogenates from animals with cysteamine-induced ulcers showed significant decreases in HCO − 3 -activated ATPase and carbonic anhydrase activities compared with controls. 3. Alkaline phosphatase activity also fell significantly in the cysteamine-treated animals, and possibly reflects the HCO − 3 -activated ATPase activity in the brush-border membrane. in contrast, activities of other marker enzymes from the brush-border membrane and from several intracellular organelles were unchanged, indicating an absence of gross organelle pathology in this experimental model. 4. Similar changes in enzyme activity were not caused by treatment with pentagastrin. Administration of cimetidine with the cysteamine did not protect the animals against ulceration, and the activity of HCO − 3 -activated ATPase was persistently decreased. However, the carbonic anhydrase activity was unaltered in this latter group, compared with controls. 5. These findings suggest that in cysteamine-induced duodenal ulceration both gastric acid hypersecretion and impaired duodenal resistance occurs. It is suggested that decreased activities of key enzymes implicated in HCO − 3 secretion may reflect the biochemical basis for the decreased mucosal resistance.