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Four months physical training significantly raised the mean proportions (%) of lauric (+0.64), myristic (+0.52), stearic (+2.06) and linoleic (+1.69) acids and lowered the mean proportions of palmitic (-1.46) and oleic (-3.46) acids in adipose tissue of 20 apparently normal men aged 20-55 yr. These changes were dependent on pretraining proportions of the fatty acids. In addition, the decreases in palmitic acid and oleic acid proportions were positively correlated (rho = 0.905, P less than 0.01, tau = 0.758, P less than 0.01). The pattern of significant correlations among adipose tissue fatty acids was altered as a result of training. We suggest that preferential mobilisation of fatty acids from adipose tissue is responsible for the change in adipose tissue fatty acid composition with increased physical training. The significant increase in adipose tissue linoleic acid proportions may be linked with the reduced risk of coronary heart disease which has been previously associated with increased physical activity.

A case of sudden unexpected death in an apparently fit and healthy young man is reported. Autopsy showed severe atherosclerotic heart disease. There was a family history of a disorder of lipid metabolism.

Plasma post-heparin hepatic lipase (PHHL) activity, plasma lipids, and high density lipoprotein cholesterol (HDL-C) levels, pulse rate at submaximal workload, and body weight were measured in 12 men during the 18 weeks physical training for their first marathon run. Reduced pulse rate at submaximal workload indicated that the men increased their physical fitness during the training period. Plasma HDL-C levels (+27%) and PHHL activity (+29%) also increased significantly after 18 weeks training. These changes were not in accord with the inverse correlation between plasma HDL-C levels and PHHL activity which was observed before training. The results of this study do not support the concept that reduced PHHL activity is mainly responsible for increased levels of plasma HDL-C with training.

Aortic dissection uncommonly occurs in multiple family members, and this association is most commonly seen in kindreds with Marfan's syndrome. There is increasing evidence that such connective tissue disturbances may not always appear in their complete phenotypic pattern. This report describes two siblings with aortic dissection. It is proposed that this suggests underlying connective tissue disease and warrants investigation of close relatives.

AN448 is a new anorectic agent, which in the dose used, is without the CNS stimulant properties of the amphetamines. Patients entering the trial were a highly resistant group at least 20 percent above ideal weight chosen from an ischaemic-hyperlipidaemic clinic population. In a double blind trial of 12 patients on the active drug and nine patients on placebo, a highly significant weight loss occurred over 12 weeks in the active group only. A significant reduction in serum cholesterol occurred independently of weight loss but there was no reduction in the serum triglycerides and no change in the lipoprotein electrophoretic pattern. The drug is shown to be effective for this group of patients and may also be useful as a cholesterol lowering agent.

A case is described where severe hypophosphataemia was induced by a widely used protocol for glucose-insulin-potassium (GIK) infusion. Hypophosphataemia was found to be a universal sequel to the use of this infusion. A new regimen for administering this agent was designed, and shown to lack the potentially serious side effect of phosphate depletion.

Long chain fatty acids were found to inhibit (Na+ + K+)-ATPase prepared from rat heart. Unsaturated and polyunsaturated fatty acids were more inhibitory than saturated fatty acids with myristic acid being the most inhibitory saturated fatty acid tested and linoleic the most inhibitory unsaturated fatty acid. As an example of fatty acid modification of the enzyme, inhibition of (Na+ + K+)-ATPase by oleate was examined. When compared to ouabain, inhibition of (Na+ + K+)-ATPase by oleate was found to be similar in that both were dependent on K+ concentration, but, in contrast to the almost instantaneous inhibition by ouabain, oleate inhibition was a slow process requiring over 20 min incubation at 37 degrees to produce maximum inhibition. Inhibition of rat heart (Na+ + K+)-ATPase by oleate was found to be readily reversible by washout. In the presence of albumin an oleate/albumin molar ratio greater than 7.5 was required for inhibition to occur. The activity of rat heart (Na+ + K+)-ATPase had a temperature optimum above 40 degrees and a discontinuous Arrhenius' plot with a transition temperature of 25 degrees. In the presence of oleate, however, the enzyme's optimum temperature decreased to below 40 degrees, the activation energy of the reaction at temperatures below 25 degrees was lowered from 24.7 kcal/mol to 12.6 kcal/mol and the enzyme had a linear Arrhenius' plot. The possibility of in vivo inhibition of cardiac (Na+ + K+)-ATPase under conditions of elevated fatty acids is discussed.