Abstract. Individual phospholipids were determined in the plasma of 24 hypercholesterolemic subjects and in 13 healthy controls. In the hypercholesterolemic group total phospholipids were increased, as were the absolute amounts of lecithin and especially sphingomyelin. Expressed as percentage of total phospholipids, sphingomyelin was increased and lecithin decreased. The absolute amount of lysolecithin was unchanged and the percentage lower than normal. Phosphatidylethanolamine was not changed. The findings are compatible with an increase of beta‐lipoproteins of normal composition in hypercholesterolemia. It is speculated whether the alteration in the phospholipid pattern may be of importance for the tendency to atherosclerosis in hypercholesterolemia.

Abstract. The individual phospholipids as well as the triglycerides, free fatty acids, total cholesterol and its non‐esterified fraction have been determined on a normal material comprising 37 men and women of different age groups. Young men exhibited significantly higher values of lysolecithin in comparison with elderly men and women irrespective of age. Incubation studies revealed a lecithin splitting activity with subsequent formation of lysolecithin and release of fatty acids. Simultaneously the well‐known lipase activity was found, splitting also the triglycerides and releasing further amounts of free fatty acids. Free cholesterol decreased to a significant extent, probably by transesterification of fatty acids released during the incubation from lecithin and probably also to a lesser degree from triglycerides. No change of sphingomyelin was noted and phosphatidylethanolamine also remained unchanged during the incubation. The reported lysolecithin increase in incubated plasma probably explains the previously reported reduced sedimentation rate of red cells added to such a plasma. The increment of free fatty acids may also contribute to the same result to a lesser extent.

Abstract. A material of 22 cases of myocardial infarction has been analysed with regard to the lipid and phospholipid levels at the acute stage of the disease, and at the lime of discharge from hospital in 12 cases. Definitely decreased values of lysolecithin have been found which highly significantly differ from a reported normal material. A slight but probably significant decrease of phosphatidylethanolamine has been observed. The FFA level is also considerably elevated in comparison with the normal material. On incubation a lysolecithin increase takes place in the plasma of patients suffering from myocardial infarction as in normal subjects, and a concomitant decrease of lecithin occurs. Simultaneously triglycerides and FFA change, the former exhibiting a highly significant decrease and the latter an increase of the same significance level. As in normal subjects an esterification of free cholesterol occurs on incubation. Total cholesterol, total lipid phosphorus and sphingomyelin retain their preincubation levels as in the normal material. The increase of lysolecithin in absolute figures is distinctly below the normal one, indicating that a diminished lecithinase activity has been observed. Cholesterol esterification on incubation is also definitely decreased, suggesting a reduced fatty acid transferase activity. After the lapse of the initial disease period the same analyses were performed. At that time most patients had returned to or approached the normal lysolecithin level of their age group. The alterations after incubation at the re‐examination are the same as at the initial stage. The possible biological and clinical significance of the reported findings is discussed.

Abstract. The increased lecithinase as well as lipase activity of post‐heparin plasma in comparison with native plasma subjected to incubation is reported. The enzymatic action gives rise to a further increased formation of lysolecithin, a concomitant diminution of lecithin and triglycerides with an appreciable liberation of fatty acids. In spite of the presence in abundance of free fatty acids no further esterification of free cholesterol takes place, in contrast to the considerable decrease of free cholesterol by transesterification from the enzymatically split lecithin when pre‐heparin plasma is subjected to incubation. Possibly an esterification “threshold level” exists in this respect. The effect of a single heparin injection on the lipid metabolism will last for about 3–4 h. Based on the available data from this report and earlier findings the possibility is discussed whether or not the clearing of lipemic plasma can be explained by the consecutive action of a lecithinase and a lipase, the first enzyme transferring the stabilizing surface layer of the chylomicra consisting of phospholipids and cholesterol into a more or less water‐soluble form, and thereafter the second enzyme can act directly on the chylomicron content of triglycerides. An experimental approach to in vitro clearing of lipemic plasma by the two enzyme systems from extraneous sources is discussed.

There has been some discussion as to whether the alkali in the pancreatic juice is delivered from reservoirs in the gland or whether it is taken direct from the blood during the pancreatic secretion. In 1928, Hammarsten & Jorpes advanced the theory that the alkali is stored in the gland as nucleic acid alkali and that this alkali bound to the nucleic acids is first taken into use when the secretion takes place. Ball [1930], after having observed that changes in the sodium and potassium content of the blood are immediately followed by changes of these ions in the pancreatic juice, concluded that the alkali in the juice is delivered direct from the blood during the secretion.If the theory advanced by Hammarsten & Jorpes is correct, and the charging of the gland with alkali proceeds at a slower rate than the discharging, with a maximum secretion, their assumption ought to be experimentally verifiable. These investigators, by means of repeated injections of secretin, caused their experimental animals (cats) to secrete maximum amounts of pancreatic juice. The animals' stomachs had been removed in order to exclude all possibility of a simultaneous secretion of gastric juice. Control cats operated upon in the same way and at the same time were used as comparative material. The first experiments were made with a view to finding out whether the secreted amounts of alkali produced any change in the alkali reserve in the blood of the experimental animals, but no such change could be demonstrated. It was also thought that if the pancreas could be worn out by powerful and sustained secretion the accumulation of acid radicals in the gland which, according to their theory, ought to take place, should bring about a reduction in the alkali reserve in the gland; such a reduction, when sufficiently advanced, should cause an increase in the degree of acidity -in the gland. Hammarsten & Jorpes produced an extract from the finely cut-up gland and made pH determinations on the extract. They observed that the degree of acidity in the extract from a normal pancreas was in all cases lower than that in the extract from the secreting pancreas. Ball [1930] took as his starting point the assumption that if the alkali in the juice on secretion comes direct from the blood, then changes in the bicarbonate content of the plasma and in the concentration of each individual cation in the blood ought immediately to affect the concentration of the ions concerned in the pancreatic juice. Ball's experiments were made on dogs, the secretion being set in motion by injections of secretin.' He administered hydrochloric acid intravenously, and produced a comparatively high reduction in the bicarbonate content of the blood; this was answered by a slight fall in the bicarbonate content of the pancreatic juice. He raised the bicarbonate content of the blood by an injection qf carbonate and the bicarbonate radical in the pancreatic juice rose. After this procedure also, a relatively large increase in the bicarbonate content of the blood was obtained but only a...