Equine CG was obtained from Professional Compounding Centers of America (Houston, TX; oocyte studies), Cal-biochem (La Jolla, CA; granulosa cell and follicle studies) or the National Hormone and Pituitary Program of the National Institute of Diabetes and Digestive and Kidney Diseases (A.F. Parlow; granulosa cell K+ studies); hCG was obtained from Serono Laboratories (Norwell, MA). The potassium-sensitive dye PBFI (the cell-permeant acetoxyl-methyl ester of potassium-binding benzofuran isophthalate) was purchased from Molecular Probes (Eugene, OR). Human recombinant caspase-1 and caspase-3 (generously provided by Dr W.W. Wong, BASF Bioresearch Corp., Worcester, MA) were prepared as N-His affinity-tagged proteins in Escherichia coli and activated prior to each experiment by dithiothreitol treatment.
Recombinant human pro-IL1p and rabbit polyclonal antibodies that recognize the pro form (numbers 02-1000) and processed form (numbers 02-1100) of human IL1p were obtained from Cis-tron Biotechnology (Pine Brook, Nj). Anti-actin monoclonal antibody C4 was from Boehringer-Mannheim (Indianapolis, IN). Doxorubicin (DXR) was from Alexis Biochemicals (San Diego, CA) and was prepared fresh in culture medium before each experiment. All other chemicals and reagents were obtained, unless otherwise noted, from Sigma Chemical Co. (St. Louis, MO).