Related Experiment Video
Updated: Jun 25, 2026
Developing a Rat Model for Bipolar Disorder
Published on: May 2, 2025
Hyperbilirubinemia-related behavioral and neuropathological changes in rats: a possible schizophrenia animal model
Maiko Hayashida1, Tsuyoshi Miyaoka, Keiko Tsuchie
1Department of Psychiatry, Shimane University Faculty of Medicine, Japan.
Background:
Patients with schizophrenia show a significantly higher frequency of hyperbilirubinemia than patients suffering from other psychiatric disorders and the general healthy population. We examined the hyperbilirubinemia on behavioral and neuropathological changes in rats as a possible animal model of schizophrenia.
Methods:
Gunn rats with severe hyperbilirubinemia (j/j), Gunn rats without severe hyperbilirubinemia (+/j), and Wistar rats were examined by open-field, social interaction, and prepulse inhibition tests. TUNEL, AgNOR and Ki-67 were also assayed on paraffin-embedded brain sections of these rats.
Results:
Compared to Wistar rats, both Gunn j/j and +/j rats showed hyperlocomotion, high sniffing scores, and low defecation scores. They showed significantly more aggressive behaviors and impaired prepulse inhibition. The numbers of Ki-67-labeled cells and AgNOR were lower and the number of TUNEL-positive cells was higher than that of Wistar rats.
Conclusions:
These results might support the neurodevelopmental hypothesis of schizophrenia. Both Gunn j/j and +/j rats may be a useful animal model and provide clues to the role of hyperbilirubinemia in schizophrenia.
