We conducted a prospective randomized trial of propranolol for the prevention of recurrent variceal bleeding in 48 patients with cirrhosis of the liver. During a follow-up period of up to 21 months, 12 of 26 patients in the propranolol group and 11 of 22 in the control group had rebleeding from esophageal varices. There was no significant difference in rebleeding between the two groups. This contrasts with a previous report of the efficacy of propranolol in preventing recurrent gastrointestinal bleeding in alcoholic cirrhosis. The difference in results may be due to the inclusion in our study of patients with other causes of cirrhosis and more severe liver disease. Propranolol may not be indicated for the prophylaxis of variceal rebleeding in such patients, and we advocate that its use be limited at present to controlled clinical trials.

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The rates of [3H]N(tau)-methylhistidine (3-MH) accumulation in the medium, following pulse labelling of cells for 48 h with [3H]methionine, were used to measure myofibrillar protein degradation. In fused C2C12 myotubes, incubation for 24 or 48 h after the labelling period gave rates of myofibrillar degradation of 38 and 42%/day. In a leucine free medium, these rates were similar; 40 and 47%/day, respectively. Using identical conditions +/- leucine, but in the absence of [3H]-methionine, rates of protein accretion and synthesis over 24-48 h were measured. From these data, rates of total protein degradation were calculated by difference and were similar to myofibrillar degradation rates. We have used the same pulse labelling protocol to assess whether the method is applicable to non-muscle cell lines based on the knowledge that 3T3 fibroblasts contain actin in the cytoskeleton. 3-MH was detected both in protein and upon its release into the medium. Actin degradation measured over a 48 h period gave a value half that obtained for total degradation, but the results suggest that the release of 3-MH by fibroblasts in vivo could be appreciable. The development of this methodology should provide a useful tool to investigate signalling mechanisms regulating actin degradation in a variety of cell types.

The dangers of inducing diuresis in patients with pulmonary oedema and normal pulmonary wedge pressures have recently been described." We report a complementary case of acute right heart failure due to right ventricular infarction complicated by hypovolaemia. In this, right ventricular output may provide an insufficient preload for the left ventricle, and there is the apparent paradox of an overloaded right ventricle and an inadequately primed "hypovolaemic" left ventricle. Failure to recognise this may lead to inappropriate diuretic or inotropic treatment and potentially irreversible hypovolaemic shock. Case report A 66-year-old tailor presented with inferior myocardial infarction. He was normotensive and well perfused, with raised jugular venous pressure. Auscultation of the heart was normal and he had no signs of left ventricular failure. Because of the raised jugular venous pressure he underwent diuresis. Over three days he became hypotensive and oliguric. Jugular venous pressure remained raised in the absence of pulmonary congestion, and he developed ankle oedema. Inotropic drugs and diuretics produced no improvement. A Swan-Ganz catheter was inserted (figure). Right atrial pressure was

The role of cyclic AMP as a second messenger in the stimulation of protein synthesis and the potential involvement of mitogen activated protein (MAP) kinase in this response was studied in L6 myoblasts. Dibutyryl-cAMP (dbt-cAMP) increased protein synthesis at 90 min and 6 h in a concentration-dependent manner. The responses at 90 min were probably mediated by increased translation as they were not blocked by actinomycin D; effects at 6 h were accompanied by increases in RNA content implying a transcriptional component. 100 nM 12-0-tetradecanoylphorbol-13-acetate (TPA), 1 nM Insulin (90 min incubations) and 100 nM vasopressin (6 h incubation) also increased protein synthesis and these responses were additive with those of 500 micron dbt-cAMP. Responses to forskolin were similar to dbt-cAMP whilst 1,9-dideoxyforskolin had no effect. Cell extracts immunoblotted with MAP kinase antibody showed bands corresponding to approx. 42, 44, 54 and 83 kDa. 500 micron dbt-cAMP elicited an increase in activity of both the 42 and 44 kDa bands when assayed by the 'in gel' method and a similar response was also observed with forskolin. TPA and vasopressin also stimulated the activity of these two isoforms, but had no significant additive or inhibitory effects when added in combination with 500 micron dbt-cAMP. In contrast, although 1 nM insulin alone had no effect, a synergistic response in terms of MAP kinase activation was observed in the presence of dbt-cAMP. The data demonstrate that cAMP stimulates protein synthesis in L6 cells and suggest a role for MAP kinase in this event.