Porcine stress syndrome: an animal model for the neuroleptic malignant syndrome?

The porcine stress syndrome is a genetic disorder of swine which, like neuroleptic malignant syndrome, is characterized by hyperthermia, muscle rigidity, and autonomic dysfunction. We investigated the porcine stress syndrome as a possible animal model for neuroleptic malignant syndrome in two ways. First, we administered haloperidol and lithium carbonate, alone and in combination, to susceptible and resistant swine. Second, we attempted to prevent the syndrome by pretreating animals with bromocriptine. Porcine stress syndrome was induced in 2 of 3 susceptible and 1 of 3 resistant swine by combined treatment with lithium and haloperidol, but was not triggered by treatment with lithium or haloperidol alone. Pretreatment with bromocriptine conferred no protection against the syndrome.