The only study that we performed was in mice injected intraperitoneally with 10 uL of BrdU labeling reagent (catalog #00-0103) per gram of body weight. Incorporation of BrdU was monitored immunohistochemically only in the small intestine. Our data showed that 2-4 hours after BrdU injection in vivo was optimal for detection of staining in small intestine. Positive staining was lighter but still visible 8 hours later, but was gone after 24 hours.
With BrdU injection in mice, it is very unlikely that labeling, at least in small intestine, will last for 3-5 days. It is likely that the BrdU signal intensity as a function of time after labeling is species- and organ-specific, since the proliferation rate of the cells being labeled determines the amount of positive staining at any particular time. Also, labeling efficiency and kinetics are dependent upon the method used to label the cells in the sample with BrdU. For example, BrdU can be administered in vivo by injection, as described above, or by adding it to the animals' drinking water for several days. Labeling kinetics may vary for different types of cells in culture as well. For example, adherent cells typically label with different kinetics than cells that grow in suspension.
Find additional tips, troubleshooting help, and resources within our Cell Analysis Support Center.
