What is the high-pitched sound at the beggining of Ronnie James Dio's "Rainbow in the Dark"?

-On the Holy Diver solo album, there's a real high-pitched sound right from the beggining of the song that's not in any of his others. What is it?Do you mean the synthesizer riff? Probably played on a keyboard.That's been played on a keyboard. It sounds so cool. Heavy but groovy :P
It'd be a synthesizer.