Detection of histidine decarboxylase in rat aorta and cultured rat aortic smooth muscle cells.
OBJECTIVE
Having previously demonstrated release of histamine from mast-cell-deficient rat aorta, the objective of this study was to determine and localize histamine synthesis capability in the aorta by detecting histidine decarboxylase (HDC), the enzyme that catalyzes histamine formation.


METHODS
Experiments were conducted with nested reverse transcription-polymerase chain reaction (nRT-PCR) to detect HDC mRNA and with immunofluorescence and western blot analysis to detect HDC protein in rat aorta, cultured rat aortic smooth muscle (RASMC) and endothelial cells (RAEC).


RESULTS
Gel electrophoresis of nRT-PCR products indicated HDC mRNA in liver, aorta and RASMC but not in RAEC or kidney. Sequence analysis confirmed that the band observed in RASMC was the target HDC amplicon. Immunofluorescence indicated the presence of HDC protein in RASMC and not in RAEC. Western Blot analysis revealed HDC protein (55 kDa) in liver, aorta, RASMC but not in RAEC or kidney.


CONCLUSIONS
The results of this study are the first to demonstrate the presence of HDC mRNA and protein in rat aorta and more specifically in RASMC, indicative of their capability to synthesize histamine.
Department of Pharmacology, Joan C. Edwards School of Medicine, Marshall University, 25704-9388, Huntington, WV 25704-9388, USA. tippens1@marshall.edu
A S
AS
Tippens
S V
SV
Davis
J R
JR
Hayes
E C
EC
Bryda
T L
TL
Green
C A
CA
Gruetter
D000818:Animals; D001011:Aorta / Q000166:cytology* / Q000201:enzymology*; D015153:Blotting, Western; D002478:Cells, Cultured; D004926:Escherichia coli / Q000235:genetics; D005455:Fluorescent Antibody Technique; D006640:Histidine Decarboxylase / Q000235:genetics* / Q000378:metabolism*; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000201:enzymology*; D032389:Myocytes, Smooth Muscle / Q000201:enzymology*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D011916:Rats, Inbred F344; D020133:Reverse Transcriptase Polymerase Chain Reaction
D012333:RNA, Messenger; D006640:Histidine Decarboxylase