Partial hippocampal pyramidal cell loss alters behavior in rats: implications for an animal model of schizophrenia

Brain Res Bull. 1991 Jun;26(6):993-6. doi: 10.1016/0361-9230(91)90268-o.

Abstract

A putative biological substrate of schizophrenia involves cellular pathology within the hippocampus. While hippocampal dysfunction is associated with impaired learning and memory, schizophrenics have been observed to acquire simple conditioned reflexes at rates superior to controls. The present study evaluates the acquisition of shuttlebox avoidance responses in animals with partial damage to hippocampus. Intraventricular microinjections of kainic acid (0.5 or 1.5 nM) were utilized to partially destroy the pyramidal cell population. Animals in the high dosage group acquired the response at rates superior to controls; the low dosage group performed at an intermediate level. Consequently, partial loss of pyramidal neurons may be sufficient to significantly alter simple acquisition. Results are discussed in reference to the "embryological hypothesis" of schizophrenia and mechanisms for induction of schizophrenic behavior in intractable seizure disorders are considered.

MeSH terms

  • Analysis of Variance
  • Animals
  • Avoidance Learning* / drug effects
  • Disease Models, Animal
  • Dose-Response Relationship, Drug
  • Grooming / drug effects
  • Hippocampus / drug effects
  • Hippocampus / pathology
  • Hippocampus / physiology*
  • Kainic Acid / toxicity*
  • Male
  • Motor Activity* / drug effects
  • Pyramidal Tracts / drug effects
  • Pyramidal Tracts / pathology
  • Pyramidal Tracts / physiology*
  • Rats
  • Rats, Inbred Strains
  • Schizophrenia / physiopathology*
  • Schizophrenic Psychology*
  • Stereotyped Behavior* / drug effects

Substances

  • Kainic Acid