Hamster costovertebral organ lipogenesis in vitro and in vivo: effects of cerulenin

An assay for lipid synthesis by hamster costovertebral organ (CVO) in vivo is described. When sodium [1-14C]acetate is injected intraperitoneally into male hamsters, maximum labeling of CVO lipids occurs after 5 min and remains constant for more than 40 min following injection. The major products of in vivo labeling are polar lipids, triglycerides, and sterols. The distribution of radiolabeled lipid products in vivo is similar to that obtained from incubation of CVO punch biopsy specimens with [1-14C]acetate in vitro. Castration results in an greater than 80% inhibition of CVO lipid synthesis as measured using in vitro or in vivo techniques. Cerulenin inhibited de novo fatty acid synthesis by the 100,000 X g supernatant of a CVO homogenate and the incorporation of [1-14C]acetate into fatty acids by CVO biopsies in vitro. Topical application of cerulenin to the CVO did not inhibit synthesis of radiolabelled lipids from [1-14C]acetate in vivo. The in vivo assay provides a necessary means of determining the physiological significance of in vitro results obtained when assaying for inhibitors of sebaceous gland lipogenesis.

Gastric morphology in ulcer patients receiving misoprostol

The effects of misoprostol on human gastric antral mucosa were investigated in patients with established diagnoses of either gastric or duodenal ulcer. All patients had pretreatment biopsy. After starting treatment with misoprostol, antral biopsies were taken at four and eight weeks and were fixed in formaldehyde. Following fixation and routine tissue processing, the slides were stained with hematoxylin and eosin. A pathologist from the laboratory preparing the slides reviewed the slides and prepared surgical pathology reports. An identical slide of each biopsy was sent to pathologists at G.D. Searle and Company who were unaware of the diagnoses and who issued an independent descriptive report. Representative cases are presented for discussion. Misoprostol was administered at doses of 100 or 200 micrograms for four or eight weeks. No cellular or mucosal changes were observed. Both groups of pathologists were unable to recognize any dose-related or structural alterations. No special studies were performed on these tissues due to their fixation and sample size. Infiltration of the mucosa by chronic inflammatory cells with a variable number of granulocytes was the most common finding. There were a few cases of goblet cell metaplasia and mild hyperplasia both before and after treatment. By the application of histochemical and immunohistochemical staining methods it is hoped that the constituents in mucus and specialized cells can be identified.