Summary: | Somatostatin is an inhibitory neuroendocrine peptide that exerts its effects through 5
functionally distinct receptor subtypes (SSTR1-5). Somatostatin analogues have been
shown to be effective in inhibiting intimal hyperplasia after balloon induced vascular
injury. However, the exact SSTR subtype responsible for the inhibitory effect of
somatostatin on intimal hyperplasia is unknown.
Purpose'. To define the presence and abundance of the SSTR-2 subtype in a rat iliac
balloon injury model of intimal hyperplasia.
Methods'. Transaortic balloon injury of the rat iliac artery was carried out. Rats were
sacrificed at 48 hours, 1 week and 1 month post injury, perfusion fixed and samples of
iliac arteries were immunostained with antibodies against SSTR 1,2, and 3. Expression of
SSTR-2 was confirmed by reverse transcriptase polymerase chain reaction (RT-PCR).
The PCR product was sequenced to confirm its identity.
Results: Immunocytochemical staining demonstrated the presence of SSTR2 on the
intimal surfaces of normal and injured vessels. SSTR2-immunoreactivity was more
prominent at 1 week and 1 month post injury compared with 48 hours post injury. There
was no immunostaining with SSTR1 and SSTR3 antibodies. PCR results confirm
elevated SSTR2 in injured arteries.
Conclusion: SSTR2 is expressed on endothelial cells in normal and injured rat vessels.
Its abundance in the injured vessel was increased up to 1 month post injury.
|