We've learned the granddaughter of film legend Clark Gable was rushed to the hospital Wednesday night after she was found unconscious at her home.
Sources close to the situation tell us ... one of Kayley Gable's friends found her on the floor of her Hollywood pad and immediately called 911.
Law enforcement sources tell us the call was made at 9:41 PM for "unspecified medical aid." Kayley -- who was also a contestant on "Paris Hilton's My New BFF" -- was transported to a local hospital by ambulance.
We're told Kayley ended up ditching the hospital after an hour or so -- claiming it was all a misunderstanding and that she had simply suffered a panic attack.