NEW ANIMAL-MODEL FOR SCHIZOPHRENIA - INTERACTIONS WITH ADRENERGIC-MECHANISMS

  • 1 January 1978
    • journal article
    • research article
    • Vol. 13  (2) , 217-225
Abstract
Amphetamine-induced stereotyped behavior in animals was proposed as a model for schizophrenia. Chronic amphetamine administration produced stereotyped behavior and a paranoid schizophreniform syndrome in man, whereas in animals a behavioral sensitization to stereotypy was evoked. Phenylethylamine (PEA), an amphetamine-like stimulant concentrated in the limbic system of the human brain, produced stereotypy in rats with a behavioral sensitization when chronically administered. In comparing amphetamine-induced stereotypy with PEA-induced stereotypy, the .alpha.-adrenergic blocking agents phentolamine and phenoxybenzamine selectively antagonized PEA stereotypy, whereas the .beta.-adrenergic blocking agent propranolol failed to alter significantly stereotypies evoked by PEA or amphetamine administration. Catecholamine depletion by .alpha.-methyl-p-tyrosine administration blocked stereotypies induced by both PEA and amphetamine, whereas selective norepinephrine [NE] depletion antagonized only PEA stereotypy; the amino acid precursors of both NE and dopamine potentiated stereotypies. PEA-elicited stereotypy, but not amphetamine-elicited stereotypy, was dependent upon [NE]; the significance of this for the PEA animal model of schizophrenia was discussed.