title: Increased cerebrospinal fluid cyclo(His-Pro) content in schizophrenia.
abstract: Cyclo(His-Pro) (CHP) is a peptide endogenous to human brain and cerebrospinal fluid (CSF). In animal studies administration of exogenous CHP augments dopaminergic neurotransmission. To explore the role of this peptide in schizophrenia, a disease characterized by a hyperdopaminergic state, we have measured CSF CHP levels in control, never-medicated schizophrenics and medicated schizophrenics. Our data show a 53% increase in CSF levels of CHP in never-medicated schizophrenics (p = 0.015), and a 25% increase in medicated schizophrenics when compared to controls. We speculate that CHP may contribute to the expression of hyperdopaminergic symptoms in schizophrenia.
authors.affiliation: Department of Medicine, Louisiana State University Medical Center, New Orleans 70112.
authors.forename: C
authors.initials: C
authors.lastname: Prasad
authors.forename: C W
authors.initials: CW
authors.lastname: Hilton
authors.forename: J B
authors.initials: JB
authors.lastname: Lohr
authors.forename: H J
authors.initials: HJ
authors.lastname: Robertson
mesh_terms: D000328:Adult; D004298:Dopamine / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010456:Peptides, Cyclic / Q000134:cerebrospinal fluid*; D010879:Piperazines / Q000134:cerebrospinal fluid*; D012559:Schizophrenia / Q000134:cerebrospinal fluid* / Q000188:drug therapy
chemical_list: D010456:Peptides, Cyclic; D010879:Piperazines; C015924:histidyl-proline diketopiperazine; D004298:Dopamine