Detail of "123496-28-6"

Reference

Formation of histamine-releasing activity from albumin by medium conditioned by endotoxin-stimulated rat peritoneal macrophages

Formation of histamine-releasing activity from albumin by medium conditioned by endotoxin-stimulated rat peritoneal macrophages. Cochrane, David E.; Boucher, William; Carraway, Robert E. (Dep. Biol., Tufts Univ., Medford, MA 02155, USA). Agents Actions, 35(1-2), 19-28 (English) 1992. CODEN: AGACBH. ISSN: 0065-4299. DOCUMENT TYPE: Journal CA Section: 15 (Immunochemistry) Section cross-reference(s): 2, 14 Incubation of bovine serum albumin (BSA), rat serum albumin or rat plasma with medium conditioned by endotoxin-stimulated rat peritoneal macrophages produced an activity that released histamine from isolated rat serosal mast cells. The amt. of histamine-releasing activity (HRA) produced increased with the length of the incubation period, with the concn. of albumin, with the no. of macrophages stimulated, and with the duration of exposure of the macrophages to endotoxin. Moreover, the formation of the HRA showed a dependency on the pH of the incubation medium with an optimum at pH 4.5. Boiling the medium conditioned by stimulated macrophages before its incubation with albumin or including the acid protease inhibitor, pepstatin, with the conditioned medium prevented the formation of HRA. The generation of HRA was not inhibited by pretreatment of the macrophages with the inhibitor of protein synthesis, cycloheximide. Media from macrophages not stimulated with endotoxin failed to generate HRA. Histamine release from mast cells in response to the HRA was inhibited by pretreatment of the cells with antimycin A and deoxyglucose or by preincubation in Ca-free Locke's soln. contg. a calcium chelating agent. When injected intradermally into anesthetized, Evan's Blue-treated rats, the generated HRA produced a change in vascular permeability that was prevented by the H1 antagonist, diphenhydramine. Treatment of the HRA with carboxypeptidase A reduced its ability to stimulate histamine release from mast cells. Histamine-releasing peptide (HRP), a neurotensin-related octapeptide, shown previously to be formed by the action of cathepsin D or pepsin on albumin, was identified by RIA in acid:acetone exts.In this experiment, several chemicals are used like 123496-28-6 and 51-45-6 of the histamine-releasing activity. Thus, the formation of HRA is due to the actions of enzymes released from macrophages acting on albumin. It is suggested that such histamine-releasing activity could be formed during the later stages of the inflammatory response and that HRP is one of the peptides present. .