Date of Degree


Document Type


Degree Name

Master of Science (MS)




Carlos Garcia


David Starkey


Christopher Pierce


Research Focus. Rheumatoid arthritis (RA) is a chronic, debilitating, autoimmune disease that causes the destruction of bone tissue and the articular structures of joints. At least 30% of RA patient populations have cognitive impairment. Acidic dopamine (DA) is the principal neuroimmunotransmitter that links the central nervous system and peripheral nervous system together. The aim of the present study was to determine the levels of DA and its two acidic metabolites: 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in arthritic induced rats, and whether their levels vary across four different parts of the brain: amygdala (AMG), front cerebral cortex (CX), hippocampus (HIP), and cerebellum (CBL). Brain protein was also assessed.

Materials and Methods. 3-month old male Lewis Rats (n=16) were randomized into either control (n=6) or treatment (n=10) groups. In the treatment group, arthritis was induced in the rats using Freund’s Adjuvant and all rats were sacrificed on day 28. Dopamine, DOPAC, and HVA levels were quantified using High Performance Liquid Chromatography technique while proteins were quantified using Bicinchroninic Acid (BCA) Protein Assay, in the four brain regions. Two-way ANOVA test was performed to determine whether brain regions, induce arthritis treatment or their interactions significantly influenced the levels of the analytes (at p<0.05).

Research Results/Findings. Levels of brain protein (C-reactive protein) were elevated in arthritic rats across all brain regions (p>0.05). Dopamine and DOPAC levels were lower in arthritic rats than controls (p>0.05). HVA levels were higher in arthritic rats compared to non-arthritic controls.

Conclusions from Research. The present study has demonstrated that C-reactive protein, dopamine, DOPAC and HVA are involved in the neurophysiology of arthritis. RA patients can benefit from treatment with dopamine agonists. However, more studies are warranted to determine the effect of DOPAC and HVA levels in the brain on dopamine utilization in arthritis.