Info

Figure 4. Quantitation of DMBT1 transcript in livers of rats treated with methapyrilene hydrochloride at 200 mg/kg at 0 and 48hr and sacrificed at 96hr. Data for 96hr came from animals that received methapyrilene hydrochloride at 200 mg/kg at 0 and 48hr and were sacrificed at 96hr. All other animals received a single dose of methapyrilene hydrochloride at 200 mg/kg at 0hr.

it results from a cascade of events initiated by the compound through an as yet unknown mechanism.

. - ■ ■

1

Control

1

2

4

24

96

1

1.0

1.5

1.8

5.6

Figure 4. Quantitation of DMBT1 transcript in livers of rats treated with methapyrilene hydrochloride at 200 mg/kg at 0 and 48hr and sacrificed at 96hr. Data for 96hr came from animals that received methapyrilene hydrochloride at 200 mg/kg at 0 and 48hr and were sacrificed at 96hr. All other animals received a single dose of methapyrilene hydrochloride at 200 mg/kg at 0hr.

DMBT1 protein induction and function

Further confirmation of the induction of DMBT1 by MP was demonstrated by immunoblotting for DMBT1 protein. An immunodetectable band at the appropriate molecular weight was observed in rat liver from MP-treated animals but not from vehicle-treated animals (Fig.5). The band was faint, consistent with the estimate that biliary epithelial cells constitute just 0.14% of the total volume of the liver (Gall and Bhatal, 1987). The apparent molecular weight of DMBT1 in our experiments (164 kDa) was similar to that reported previously for the expressed cDNA for ebnerin, but was smaller than what was detected in VEG of

Western blot data

Treated Untreated

Treated Untreated

Apparent MW of DMBT1 is 164 kDa, consistent with theoretical and published

Figure 5. Western blot of liver protein from rats treated with methapyrilene hydrochloride at 200 mg/kg at 0 and 48hr and sacrificed at 96hr. An apparent molecular weight of 165 kDa was determined for the immunodetectable band in animals treated with methapryilene hydrochloride at 200 mg/kg at 0 and 48hr and sacrificed at 96hr.

Apparent MW of DMBT1 is 164 kDa, consistent with theoretical and published

Figure 5. Western blot of liver protein from rats treated with methapyrilene hydrochloride at 200 mg/kg at 0 and 48hr and sacrificed at 96hr. An apparent molecular weight of 165 kDa was determined for the immunodetectable band in animals treated with methapryilene hydrochloride at 200 mg/kg at 0 and 48hr and sacrificed at 96hr.

rat tongue (Li and Snyder, 1995). Splice variants and differences in extent of protein glycosylation are both likely to contribute to the apparent difference in molecular weight of DMBT1 in these different tissues.

DMBT1 protein has been localized by other investigators and ourselves to biliary epithelia and oval cells (Bisgaard et al., 2002; Kadura et al., 2005), as well as epithelial cells in other tissues (Ma et al., 2001; Mollenhauer et al., 2001). The proteins encoded by transcripts of this gene appear to play a significant role in terminal differentiation of epithelial cells of the prostate and vas deferens (Ma et al., 2001) and of kidney epithelial cells cultured in vitro, including polarity reversal of the intercalated cells taken from rabbit kidney (van Adelsberg et al., 1994; Takito et al., 1999; Al-Awqati et al., 2000). It is likely that DMBT1 plays a role in oval cell differentiation into biliary epithelial cells, and may involve proteinprotein interactions with extracellular matrix proteins such as galectin-3 (Hikita et al., 2000).

0 0

Post a comment