Alkaline phosphatase expression in tissues from glucocorticoid-treated dogs.
OBJECTIVE
To determine the effect of glucocorticoids on the induction of alkaline phosphatase (ALP) isoenzymes in the liver, kidneys, and intestinal mucosa, 3 tissues that are principally responsible for ALP synthesis in dogs.


METHODS
Tissues from the liver, kidneys, and intestinal mucosa of 6 dogs treated with 1 mg of prednisone/kg/d for 32 days and 6 untreated control dogs.


METHODS
Using canine-specific primers for the ALP isoenzymes, a reverse transcription-polymerase chain reaction assay was designed to measure liver ALP (LALP) and intestinal ALP (IALP) mRNA and heterogeneous nuclear RNA (hnRNA) expression in tissues from the liver and kidneys and intestinal mucosa of glucocorticoid-treated and control dogs. Tissue ALP isoenzyme activities were compared between the groups.


RESULTS
The LALP activity and mRNA concentrations increased in tissues of the liver and kidneys in dogs treated with prednisone, whereas LALP hnRNA increased only in liver tissues. The IALP activity and mRNA expression increased in intestinal mucosa and liver tissues in prednisone-treated dogs. We did not detect an increase in IALP hnRNA expression in these tissues.


CONCLUSIONS
Synthesis of ALP is increased in the liver, kidneys, and intestinal mucosa of dogs in response to prednisone treatment. This response appears to be regulated at the transcriptional level, but mechanisms may differ between LALP and IALP.
Wiedmeyer
Charles E
CE
Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Illinois, Urbana 61802, USA.
Solter
Philip E
PE
Hoffmann
Walter E
WE
D000469:Alkaline Phosphatase / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D000818:Animals; D004285:Dogs / Q000378:metabolism*; D004790:Enzyme Induction / Q000187:drug effects; D005938:Glucocorticoids / Q000494:pharmacology*; D007413:Intestinal Mucosa / Q000187:drug effects / Q000201:enzymology; D007527:Isoenzymes / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism; D007668:Kidney / Q000187:drug effects / Q000201:enzymology; D008099:Liver / Q000187:drug effects / Q000201:enzymology; D008297:Male; D011241:Prednisone / Q000494:pharmacology*; D012332:RNA, Heterogeneous Nuclear / Q000737:chemistry / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary
D005938:Glucocorticoids; D007527:Isoenzymes; D012332:RNA, Heterogeneous Nuclear; D000469:Alkaline Phosphatase; D011241:Prednisone