[Stimulation of neuropeptide Y on heat shock protein expression in renal vascular smooth muscle and the inhibition thereon by losartan].
OBJECTIVE
To study the effect of neuropeptide Y (NPY) on the expression of heat shock protein 70 (HSP70) in vascular smooth muscle cells (VSMCs) of renal arteries.


METHODS
The renal veins of SD rats were isolated and broken into pieces. The VSMCs were cultured and then divided into 3 groups, neuropeptide Y (NPY), NPY + losartan, and serum-free DMEM were added into the culture respectively. Automated MTT colorimetric microassay and quantitative immunocytochemistry were used to detect the expression of heat shock protein (HSP70) in the proliferating VSMCs.


RESULTS
The fluorescence intensity of labeled HPS70 in the NPY group was 1,825.10 +/- 115.55, significantly stronger than that in the control group (1595.83 +/- 186.54, P < 0.05) and the fluorescence intensity of labeled HPS70 in the NPY + losartan group (1 658.54 +/- 183.78) was not significantly different from that in the control group (P > 0.05). The MTT-OD in NPY group was 0.2626 +/- 0.0025, significantly higher than that in the control group (0.2239 +/- 0.0010, P < 0.01). and the MTT-OD in NPY + losartan group was 0.2440 +/- 0.0013, significantly lower than that in the control group (P < 0.05).


CONCLUSIONS
NPY stimulates the proliferation of renal VSMC, promotes the expression of HPS70, and may cause hypertension. Losartan reduces the NPY stimulation over VSMC proliferation and relevant expression of intracellular HSP70.
Zhong
Wei-de
WD
Department of Urology, First People's Hospital Affiliated to Guangzhou Medical College, Guangzhou 510180, China.
Zeng
Guang-qiao
GQ
Hu
Jian-bo
JB
Cai
Yue-bin
YB
Liu
Jian-kang
JK
Huang
Shao-hua
SH
Chen
Min-sheng
MS
Wei
Hong-ai
HA
D000818:Animals; D002455:Cell Division / Q000187:drug effects; D018840:HSP70 Heat-Shock Proteins / Q000096:biosynthesis*; D019808:Losartan / Q000494:pharmacology*; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D009478:Neuropeptide Y / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012077:Renal Artery / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism
D018840:HSP70 Heat-Shock Proteins; D009478:Neuropeptide Y; D019808:Losartan