CINCINNATI, OHIO -- The latest challenge to the Horseracing Integrity and Safety Act (HISA) was the first case before the three judges selected to weigh in on the law's constitutionality Wednesday in the United States Court of Appeals for the Sixth Circuit, in Cincinnati. The plaintiffs comprise the state of Louisiana; Oklahoma and its racing commission, plus West Virginia and its racing commission. Three Oklahoma tracks-Remington Park, Will Rogers Downs, and Fair Meadows-are also plaintiffs, as are the Oklahoma Quarter Horse Association, the U.S. Trotting Association, and Hanover Shoe Farms,...