Acta Academiae Medicinae Sinica

Acta Academiae Medicinae Sinica

Acta Academiae Medicinae Sinica ›› 2006, Vol. 28 ›› Issue (6): 770-775.

• Original Articles • Previous Articles     Next Articles

Renin-Angiotensin System in Mesenteric Adipose Tissues in
Rats with Metabolic Syndrome

MA Li-qun,ZHANG Li-li, ZHANG Ya-ping,WANG Li- juan,LI Zhi-bing,
CAO Ting-bing,LIU Dao-yan, ZHU Zhi-ming
  

  1. Department of Hypertension and Endocrinology, Daping Hospital, Third Military Medical University, Chongqing 400042, China
  • Received:2006-06-27 Revised:1900-01-01 Online:2006-12-30 Published:2006-12-30
  • Contact: LIU Dao-yan

Abstract: ABSTRACT:Objective To investigate the renin-angiotensin system (RAS) in mesenteric adipose ti- ssues and effect of angiotensin Ⅱ on adipocyte differentiation. Methods Thirty normal 8-week-old male Wis- tar rats were divided into groups on normal diet and high-fat diet. The rats on high-fat diet for 24 weeks deve- loped the metabolic syndrome respectively. The mRNA and protein expression of mesenteric adipose tissue were measured by reverse transcription-polymerase chain reaction(RT-PCR) and Western blot. Lipid drop in 3T3-L1 preadipocytes and mature adipocytes were observed using oil-red O staining. The fluorescence microscope was used to detect cytosolic-free calcium in 3T3-L1 predipocytes and mature adipocytes. Results The expressions of angiotensinogen, angiotensin converting enzyme, angiotensin Ⅱ receptor type 1 in mesenteric adipose tissue were significantly increased in rats with metabolic syndrome compared with those in rats on normal diet (P<0.05,P<0.01=. After administration of angiotensin Ⅱ, no lipid droplet in 3T3-L1 preadipocytes and adipocytes were observed, however, intensive lipid droplet in adipocyte was found after administration of captopril and candesartan. Angiotensin Ⅱ increased the intracellular-free calcium concentration in preadipocytes(P<0.01), which was blocked by captopril and candesartan; in contrast, angiotensin Ⅱ effect was blunt in mature adipocyte. Captopril and candesartan partially recovered the angiotensin Ⅱ-mediated increase of cytosolic-free calcium. Conclusion RAS in the mesenteric adipose tissues is active in rats with metabolic syndrome, and antagonization of RAS can recover the lipogenesis of adipocyte.

Key words: renin-anciotensin system, anciotensin Ⅱ, 3t3-l1 preadipocyte, adipose tussue, intracellular ca2+ level