Behavioral effects of methylene blue on an animal model of sodium azide-induced metabolic deficits

Simple item page
dc.contributor.advisorGonzález-Lima, Francisco, 1955-en
dc.creatorCallaway, Narriman Lee, 1953-en
dc.date.accessioned2011-06-29T21:06:46Zen
dc.date.available2011-06-29T21:06:46Zen
dc.date.issued2003-08en
dc.descriptiontexten
dc.description.abstractIn some neurodegenerative diseases, the activity of cytochrome c oxidase, an enzyme necessary for aerobic energy production, is decreased. Sodium azide, reversibly inhibits cytochrome c oxidase in the electron-transport chain. Behavioral deficits produced by sodium azide in animal models are similar to those found in neurodegenerative diseases in humans. In the experiments described here, sodium azide was systemically infused via an osmotic pump implanted during surgery in Sprague Dawley rats. They were assessed in an open field test, Morris water maze, and a spontaneous alternation test. Histochemical analysis of cytochrome c oxidase activity was conducted on brain, skeletal muscle, and cardiac muscle sections. The sodium azide group showed significant decreases in spontaneous activity in the open field test, decreased learning and memory retention in the Morris water maze, but no differences in the spontaneous alternation test. Pharmacological intervention that could compensate for the reduction of cytochrome c oxidase activity in neurons may be beneficial in the treatment of neurodegenerative diseases. One such candidate, methylene blue was administered to Sprague-Dawley rats after training, in the memory consolidation period, and its effects assessed in a probe test for memory retention in a baited holeboard maze. The percentage of visits to baited holes compared to all hole-visits was significantly higher in the methylene blue group. In the final experiment, Sprague-Dawley rats were assigned to one of three treatment groups: sodium azide, sodium azide plus methylene blue, and control. They were assessed in a probe test for memory retention in a baited holeboard maze. Methylene blue was successful in restoring memory retention inhibited by the sodium azide. The memory score for the sodium azide group was significantly less than the control and methylene blue group. In vitro studies have shown that methylene blue can accept electrons in the electron-transport chain in mitochondria. Methylene blue may compensate for decreased cytochrome c oxidase activity by accepting electrons upstream from cytochrome c oxidase and shuttling electrons to molecular oxygen, a step necessary for oxidative phosphorylation. Compensating for impaired mitochondrial respiration makes methylene blue a candidate for further study as a treatment in neurodegenerative diseases.
dc.description.departmentPsychologyen
dc.format.mediumelectronicen
dc.identifier.urihttp://hdl.handle.net/2152/11998en
dc.language.isoengen
dc.rightsCopyright is held by the author. Presentation of this material on the Libraries' web site by University Libraries, The University of Texas at Austin was made possible under a limited license grant from the author who has retained all copyrights in the works.en
dc.rights.restrictionRestricteden
dc.subjectMethylene blueen
dc.subjectSodium compoundsen
dc.subjectNervous system--Degenerationen
dc.titleBehavioral effects of methylene blue on an animal model of sodium azide-induced metabolic deficitsen
thesis.degree.departmentPsychologyen
thesis.degree.disciplinePsychologyen
thesis.degree.grantorThe University of Texas at Austinen
thesis.degree.levelDoctoralen
thesis.degree.nameDoctor of Philosophyen

Access full-text files

Original bundle

Now showing 1 - 1 of 1
No Thumbnail Available
Name:
callawaynl036.pdf
Size:
310.54 KB
Format:
Adobe Portable Document Format
Description:
Restricted to EID users
Download

License bundle

Now showing 1 - 1 of 1
No Thumbnail Available
Name:
license.txt
Size:
1.66 KB
Format:
Item-specific license agreed upon to submission
Description:
Download

Collections

UT Electronic Theses and Dissertations