The Beneficial, Powerful As well as ZD1839

Double heterozygous Ascl3EGFP-Cre/+/R26DTA/+ mice were born at the expected Mendelian frequencies, although they were smaller and showed a high rate of morbidity. This was often manifested at the age of 2�C3 weeks, although many animals survived to adulthood. As Ascl3 expression is not confined to the salivary gland (unpublished observations), we attribute the lower body mass and increased morbidity to other systemic effects. Double heterozygous Ascl3EGFP-Cre/+/R26DTA/+ NK cell mice developed morphologically normal salivary glands, although the glands were significantly smaller in size than those of wild type littermates [female Ascl+/+/R26DTA/+ 29.4 �� 5.3 mg (n?=?6; age?=?2 months); female Ascl3EGFP-Cre/+/R26DTA/+ 23.3?��?2.9?mg (n?=?6; age?=?2 months); P?ZD1839 cell line type, knockout and ablation mice. Although the Ascl3+ progenitor cells should be ablated, no significant difference in the duct cell to total cell ratio of the area was detected [Ascl+/+ 27.0?��?5.1%; Ascl3EGFP-Cre/ EGFP-Cre 25.4?��?6.1%; Ascl3EGFP-Cre/+/R26DTA/+ 24.7?��?6.4%; (n?=?9 measurements per group)]. To ascertain that the DTA locus is efficiently activated in Ascl3-expressing cells, we performed immunohistochemical analysis, taking advantage of the specific localization of the Nkcc1 and KCa1.1 transporters in Ascl3+ progenitor cells. Immunohistochemistry with antibody to Nkcc1 confirmed that activation of the DTA gene in the double heterozygotes caused nearly complete ablation of the Ascl3+ progenitor cells (Fig.?4B and C). In addition, nearly all KCa1.1-positive cells are absent from the ducts of double heterozygous Ascl3EGFP-Cre/+/R26DTA/+ mice ( Fig.?4D and E). Although we have shown that duct-specific expression of Nkcc1 may be dependent on the presence of the Ascl3 transcription factor ( Fig.?1G), the Ascl3EGFP-Cre/+/R26DTA/+ mice retain one intact copy of the Ascl3 locus ( Fig.?4A), so Nkcc1 expression should be unaffected. We conclude that the absence of Nkcc1+ cells in the ducts of Ascl3EGFP-Cre/+/R26DTA/+ mice is GSI-IX due to the specific ablation of these cells by Cre-mediated activation of the DTA gene. Cre-positive cells were not found in Ascl3EGFP-Cre/+/R26DTA/+ animals, but were readily detected in control Ascl3EGFP-Cre/+/R26+/+ littermates (data not shown). The acinar cells in salivary glands of Ascl3EGFP-Cre/+/R26DTA/+ mice appear to be normally differentiated, as determined by immunohistochemistry for several cell-specific markers, including aquaporin 5 (data not shown), and Nkcc1 ( Fig.?4C). Furthermore, RT-PCR to test expression levels of the duct cell markers Cp2L1, cKit, Keratin 5, and Sca-1 did not reveal significant changes (data not shown). To test the function of the glands in Ascl3EGFP-Cre/+/R26DTA/+ mice, ex vivo submandibular gland perfusion was performed, following stimulation with isoproterenol and carbachol, as described earlier ( Romanenko et al.