[Heterogeneity changes in secretion ability of monocyte/macrophage and its significance after trauma hemorrhage in rat].

Objective: To investigate the relationship between the heterogeneity in secretion ability of monocyte (Mo)/macrophage and the immune dysfunction after severe trauma.

Methods: Twenty-four healthy Wistar rats were randomly divided into normal control group and trauma hemorrhage 1, 4 and 7 days groups. The contents of interleukin-6 (IL-6) and IL-10 secretion of Mo/macrophage from different anatomical regions were determined by radioimmunoassay.

Results: (1)In normal rats, the ability to secrete IL-6 and IL-10 was different among alveolar macrophages (AM), peritoneal macrophages (PM) and Mo. PM showed the highest ability to secrete IL-10 while Mo had the highest ability to secrete IL-6. (2)After trauma hemorrhage, the secretion of IL-6 and IL-10 by AM were increased dramatically. On the contrary, the secretion of IL-6 by PM was declined from the 1st day to the 4th day, then increased even over that of the normal control group on the 7th day. However, the secretion of IL-10 by PM was significantly elevated on the 1st day after trauma hemorrhage, peaking on the 4th day, and only slight lowering was found on the 7th day. The secretion of IL-6 by Mo was declined gradually all the time, reaching the lowest point on the 7th day. On the contrary, the secretion of IL-10 by Mo was increasing, reaching its peak on the 7th day.

Conclusion: The heterogeneity of secretion ability of Mo/macrophage obtained from different anatomical regions is present under normal condition, and is more obvious following a severe injury. This change may play an important role in the immune dysfunction and the development of complications after trauma.