FIG. 8.

Mtgr1^−/− mice display an accumulation of cycling cells in the crypts of the small intestines and colons. (A) Proliferation in the small intestine. Proliferating cells were detected in sections of the jejunum from 8-week-old wild-type (WT) and Mtgr1-null mice by immunohistochemistry with anti-Ki-67. Positive staining is brown, with a blue hematoxylin counterstain. Graph shows the quantification of Ki-67-positive cells. Ki-67-positive cells from 100 consecutive histologically complete crypts were counted, and the average number of positive cells per crypt was calculated. Error bars, standard deviations. (B) Inactivation of Mtgr1 leads to the accumulation of cycling cells in the crypts of the colon. Proliferating cells were detected in sections of the colon from 8-week-old WT and Mtgr1-null mice by immunohistochemistry with anti-BrdU 2 h after administration of BrdU. Graph shows the quantification of the average number of positive cells per crypt. Error bars, standard deviations.