Assessment of function of histamine using histidine decarboxylase gene-manupulated mice

点击翻译按钮获取中文摘要

We estimated the role of histamine in the in vivo situation using histidine decarboxylase gene knockout mice generated by us. This gene is expressed in the cells able to produce histamine, which are mast cell, basophil, neron, gastric cell, etc. We clarified the activity of histamine in various allergic diseases, sleep state and secretion of gastric juice. We also newly clarified the relation of histamine to infection and chronic granuloma. For example, in the systemic anaphylaxis reaction, histamine plays a important role for the control of body temperature and respiration, but it does not affect the blood pressure. The knockout mice show electroencepharogram typical for the sleeping wave during waking time. The secretion of gastric juice was induced by gastrin in the wild type mice however it was seased in the knockout mice.The existence of histamine retard the recovery from peritonitis produced by intraperitoneal injection of E..coli. Histamine is important for the chronic granuloma formation triggered with subcutaneous cotton thread implantation. In addition to these in vivo phenotypes we observed intriguing evidence using bone marrow-derived mast cells. Onece we cultured the mast cell in the medium containing histamine, these histamine were absorbed into the secretory granules and could be secreted after the stimulation with lgE and anti-IgE.