Birds exhibit seasonal-dependent behavior . Seasonal changes in activity, sleep, and RF have been linked to seasonal changes in the human central nervous system (CNS). For example, in voles, changes in RF occur as a function of season, since a gradual loss of RF occurs during the winter, and this is associated with a loss of restful sleep and decreased glucocorticoid levels . This study records brain levels of NPY in four time periods: breeding (September), post-breeding (December), regressed (March), and the transition from breeding to the post-breeding phase (June) in Spotted Munia. NPY levels are correlated with seasonal changes in sleep characteristics. NPY levels increase in September, when mating season begins, suggesting increased sleep in the summer. NPY levels are high in December, especially in the hyperpallium apicale (HA) and optic tectum (TeO), signifying that sleep is greater in the post-breeding season. In contrast, NPY levels drop significantly in March, the time when the birds revert back to the breeding stage. This suggests that NPY levels are greater in March when the birds are regressing. These findings in the bird correspond with results in humans that suggest a correlation between reduced NPY activity and sleepiness in the seasons in which people feel less alert than usual. This study establishes a foundation for future research into the relationship between NPY levels and antipsychotic medications currently used in humans.
Birds have unique neural circuits that are anatomically different than those in mammals. Close similarities in the anatomy of the avian brain have led to the discovery of many pharmacologic targets, which, in the clinical arena are of considerable interest. Changes in NPY levels in the brain are strongly linked to seasonal changes in sleep duration and disturbances in voles. Moreover, correlation has been found between NPY levels and sleep in humans. In humans, schizophrenia, characterized by psychotic symptoms, is typically treated with antipsychotic medications; although, these medications are expensive and can have unwanted side effects. This study looks at NPY levels in brain structure of Spotted Munia and in humans with schizophrenia. NPY expression was observed in the following regions of the bird brain: HA, HP, TeO, and RoT. d2c66b5586