Cellular damage in mouse peritoneal macrophages exposed to cholesteryl linoleate.

Mouse peritoneal macrophages readily oxidize cholesteryl linoleate/bovine serum albumin emulsions to produce soluble lipid oxidation products, some of the latter being thought to cause cell damage. Mouse peritoneal macrophages were therefore incubated in the presence of cholesteryl linoleate/bovine serum albumin emulsion with and without the addition of dl-alpha tocopherol. The macrophages were observed morphologically and cell damage was estimated by three methods: trypan blue exclusion, lactate dehydrogenase release and tritiated adenine release.

Oxygen radicals and atherosclerosis.

There is increasing evidence that lipids, especially those in low density lipoprotein, may be oxidised during the development of atherosclerotic lesions. The lipid-laden "foam cells" of atherosclerosis are macrophages, which are known to produce oxygen radicals in their microbicidal role. The same process could result in oxidation of lipid or lipoprotein in atherosclerosis.

Induction of mutations in mouse lymphoma L5178Y cells by ethylmethanesulphonate, benzidine and benzo[a]pyrene.

As part of the third UKEMS collaborative trial, the induction of mutations in mouse lymphoma L5178Y cells was analysed by an agar cloning method. The method used was based on the published methods of Clive and co-workers and Amacher and co-workers. Mutations at the thymidine kinase (tk) locus were analysed following exposure to ethylmethanesulphonate (EMS) in the absence of S9 mix, benzo[a]pyrene (B[a]P) in the presence of S9 mix and benzidine (BZD) in the absence and presence of S9 mix.