Extracellular adenosine triphosphate affects systemic and kidney immune cell populations in pregnant rats.

PROBLEM Changes in the systemic immune response are found in preeclampsia. This may be related to high extracellular adenosine triphosphate (ATP) levels. The question arose whether ATP could affect immune responses in pregnancy. Previously, we investigated whether ATP affected monocyte activation and subpopulations. Here, we investigated ATP-induced changes in other immune cell populations in pregnant rats, systemically and in the kidney, an affected organ in preeclampsia. METHOD OF STUDY Using flow cytometry or immunohistochemistry, blood and kidney leukocytes were studied in pregnant and non-pregnant rats at different intervals after ATP or saline infusion. RESULTS Adenosine triphosphate (ATP) infusion induced increased peripheral blood non-classical monocytes and decreased T lymphocyte subsets in pregnant rats only, higher glomerular macrophage and T lymphocyte numbers in non-pregnant animals 1 day after infusion, and higher glomerular macrophage numbers in pregnant rats 6 days after infusion. CONCLUSION Adenosine triphosphate (ATP) infusion in pregnant rats induced a pregnancy-specific inflammatory response. Increased ATP levels could potentially contribute to development of the inflammatory response of preeclampsia.