Jason Priestley suffers concussion after falling off horse on set

Former "Beverly Hills, 90210" star Jason Priestley thanked well-wishers yesterday after being hospitalized Monday while shooting the TV series "The Code" in Toronto. "Hey guys, thanks for all the kind words," tweeted Priestley. "It's true, I did get thrown off a horse on set. I got my bell rung pretty good. Because I have a history of concussions, they took me to see a neurologist for an assessment. He advised I take a few days off as I had suffered a concussion. But I am definitely on the mend and looking forward to getting back to work. . . . " Priestley, 46, stars in the film as an ex-pro hockey player turned private detective.