Introducing New Cats to Resident Cat?

We have a neutered male cat who we have had as the only cat in the house. Our friend let us look after a mother cat and her daughter at our house and the male and the mother kind of sniff and hiss a little. But the male reaction to the kitten is strange to me. He look like he's playing with her, but he keeps going for the throat. Is this just a dominance thing for him and what should I do?