Expression of subtypes of somatostatin receptors in hepatic stellate cells.
OBJECTIVE
To elucidate the mechanism by which somatostatin and its analogue exert the influence on liver fibrosis, and to investigate the mRNA expression of somatostatin receptors subtypes (SSTRs) and the distribution of somatostatin analogue octreotide in rat hepatic stellate cells (HSCs).


METHODS
HSCs were isolated from Sprague Dawley (SD) rats by in situ perfusion and density gradient centrifugation. After several passages, the mRNA expression of 5 subtypes of SSTRs were assessed by reverse transcription-polymerase chain reaction (RT-PCR). HSCs were planted on coverslip and co-cultured with octreotide tagged by FITC. Then the distribution of FITC fluorescence was observed under laser scanning confocal microscope (LSCM) in 12-24 h.


RESULTS
There were mRNA expression of SSTR2, SSTR3 and SSTR5 but not SSTR1 and SSTR4 in SD rat HSCs. The mRNA expression level of SSTR2 was significantly higher than that of other subtypes (P<0.01). FITC fluorescence of octreotide was clearly observed on the surface and in the cytoplasm, but not in the nuclei of HSCs under LSCM.


CONCLUSIONS
The effect exerted by somatostatin and its analogues on HSCs may mainly depend on the expression of SSTR2, SSTR3 and SSTR5. Octreotide can perfectly combine with HSCs, and thereby exerts its biological activity on regulating the characters of active HSCs. This provides a potential prevention and management against liver fibrosis.
Song
Sheng-Han
SH
Department of Hepatobiliary Surgery, Peking University People's Hospital, Beijing 100044, China.
Leng
Xi-Sheng
XS
Li
Tao
T
Qin
Zhi-Zhong
ZZ
Peng
Ji-Run
JR
Zhao
Li
L
Wei
Yu-Hua
YH
Yu
Xin
X
D000818:Animals; D002478:Cells, Cultured; D016650:Fluorescein-5-isothiocyanate; D005456:Fluorescent Dyes; D005765:Gastrointestinal Agents; D015870:Gene Expression; D022781:Hepatocytes / Q000166:cytology / Q000502:physiology*; D008297:Male; D008565:Membrane Proteins; D015282:Octreotide; D051381:Rats; D017207:Rats, Sprague-Dawley; D017481:Receptors, Somatostatin / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods
D005456:Fluorescent Dyes; D005765:Gastrointestinal Agents; D008565:Membrane Proteins; D017481:Receptors, Somatostatin; C103631:somatostatin receptor 3; C098681:somatostatin receptor subtype-4; C101130:somatostatin receptor type 1; C094573:somatostatin receptor 5; C093733:somatostatin receptor 2; D016650:Fluorescein-5-isothiocyanate; D015282:Octreotide