Samuel Charles Hammonds

Major: Biology

University Honors with Honors in Biology

Supervisor: Dr. Richard M. Dillaman

COMPARISON OF 5-BROMO-2’-DEOXYURIDINE (BrdU) AND 5-

EHTYNYL-2’-DEOXYURIDINE (EdU) AS FLUORESCENT REAGENTS

FOR LABELING NUCLEI IN HEPATOYCTES AND MYOCYTES

OF THE BLACK SEA BASS (Centropristis striata)

While most vertebrate tissues grow by hyperplasia or the accumulation of more cells through mitotic division, skeletal muscle increases in size by both hyperplasia and hypertrophy of existing cells that do not undergo further mitotic division after fusing with the myotome. This is because these cells are thought to terminally differentiate upon entry into the myotome. However, the recent development of 5-bromo-2’-deoxyuridine (BrdU) and 5-ethynyl-2’- deoxyuridine (EdU) as fluorescent reagents for labeling nuclei provides new tools to measure mitotic rates and cell recruitment within tissues. This study employs these two compounds for two purposes: to compare the relative effectiveness of BrdU and EdU and to use these compounds to establish mitotic rates for muscle and liver tissue within Black Sea Bass (Centropristis striata) over a 24 hour and one month interval. It was found that while BrdU is effective in labeling dividing cells, the denaturing process necessary to allow the anti-BrdU antibody access to BrdU reduces the quality of images received after treatment. Due to the relatively mild treatment associated with EdU, higher quality images were collected. Therefore I concluded that EdU treatment is more effective than BrdU. I was able to determine a mitotic rate for both tissues at 24 hour and 1 month, but it was determined that for more accurate rates, a constant perfusion of EdU would preferable.