Plans to open a medical school at UC Riverside next year appeared uncertain Wednesday after officials announced that the school had been denied initial accreditation because of concerns about the cash-strapped state's ability to provide funding. The first 50 students were expected to enroll next summer at the medical school, which would be the sixth in the UC system. The school, approved by UC regents in 2008, is intended to ease a physician shortage in the Inland Empire area and to bolster UC Riverside's academic reputation. UC officials have 30 days to appeal the denial of preliminary accreditation and to scramble for a commitment of about $10 million a year in state funding. If the effort fails, the first class won't start until at least 2013 as the school keeps trying, UC Riverside Chancellor Timothy P. White said. "We are going to redouble our efforts to seek these sustaining and recurring funds from the folks in Sacramento," White said in a conference call with reporters Wednesday afternoon. He acknowledged that it would be a tough task, given the state's deficit and continuing turmoil in Sacramento over the budget.