This study was designed to examine whether endothelin is released from the intima of intact arteries, and whether endothelium-derived nitric oxide regulates its production. Endothelin was detected in the incubating medium of unstimulated pig aortae with, but not in those without endothelium. In preparations with endothelium, thrombin (2-6 U/ml) and the calcium ionophore A23187 (10' M) stimulate...

AIM To investigate the ability of natural chymase inhibitors to modulate histamine release from human mast cells. METHODS Enzymatically dispersed cells from human lung, tonsil, and skin were challenged with anti-IgE or calcium ionophore A23187 in the absence or presence of the natural chymase inhibitors secretory leukocyte protease inhibitor (SLPI) and alpha(1)-antitrypsin, then histamine rel...

OBJECTIVE There is evidence for a relationship between endothelial dysfunction and cardiovascular disease, but a causative role for oxidative stress remains to be determined. METHODS AND RESULTS We studied 188 patients with severe coronary artery disease (CAD), of whom 51 were age and sex matched with 51 healthy controls undergoing varicose vein surgery. Relaxation of saphenous vein to calciu...

Cyclooxygenase (COX)-1 and hematopoietic prostaglandin (PG) D synthase (H-PGDS) proteins, which are both involved in the arachidonate cascade, were stable in human megakaryocytic MEG-01 cells. In contrast, once the intracellular calcium level was increased by treatment with a calcium ionophore, both protein levels rapidly decreased with a half-life of less than 30 and 120 min for COX-1 and H-PG...

IONOMYCIN-INDUCED Ca CYTOSOLIC INCREASE IS NOT INDUCING MASSIVE APOPTOSIS OF Ba/F3 CELLS (Abstract): It was shown that a novel immunotherapy using ex vivo activated splenocytes is capable of promoting survival and hematopoietic recovery after syngeneic and semiallogeneic bone marrow transplantation in BALB/c mice subjected to a lethal dose of total body irradiation. We tested the hypothesis tha...

A swelling response by the polaroplast organelle initiated microsporidian invasion tube extrusions by Glugea hertwigi spores. The tumescence was induced by the displacement of internal calcium. Sodium citrate, phosphate, and the calcium ionophore A23187 were effective in initiating polaroplast swelling and spore discharge; however, the addition of external CaCl2 switched the expanded polaroplas...

Because long-term pulmonary artery (PA) obstruction is associated with expansion of the systemic blood supply to the lung, chronic ischemia may not occur, and endothelium nitric oxide synthase (eNOS) function may be preserved in postobstructive pulmonary arteries. To test this hypothesis, we studied piglets 2 d or 5 wk after left PA ligation or a sham operation. We measured left lung ATP and la...