Publication Date


Document Type


Committee Members

James Olson (Committee Chair), John Pearson (Committee Member), Christopher Wyatt (Committee Member)

Degree Name

Master of Science (MS)


Osmotic brain edema or chronic treatment with desipramine alters brain water permeability. In this study we investigated aquaporin 4 expression and distribution in these two conditions. Brain edema development was induced by intraperitoneal water injection. Blood serum osmolality decreased from 296 ± 1 mOsm to 278 ± 2 mOsm within 15 min. Cerebral cortex water content increased from 79.8 ± 0.2 % to 81.3 ± 0.5% during 120 min of this hyposmotic exposure. Aquaporin 4 immunostaining intensity at the astrocytic endfeet increased in water injected animals from 2.6 ± 0.04 intensity unites (IU) to 3.2 ± 0.21 IU, while total brain AQP4 expression remained unaltered. Chronic treatment with desipramine showed no significant change in serum osmolality or cerebral cortex water content. Similar to water injected animals, aquaporin 4 immunostaining intensity in chronic desipramine animals increased at the astrocytic endfeet (2.5 ± 0.04 IU to 3.0 ± 0.13) but total cortical AQP4 expression was again unaltered. These experiments suggest that decreased brain water permeability caused by osmotic brain edema is not a result of decreased AQP4 expression or localization of astroglial endfeet. However chronic treatment with desipramine increases AQP4 immunostaining at the astrocytic endfeet without increasing overall AQP4 expression.

Page Count


Department or Program

Department of Neuroscience, Cell Biology & Physiology

Year Degree Awarded


Included in

Anatomy Commons