Tetrahydrobiopterin postpones left ventricular diastolic dysfunction through increasing nitric oxide production

• DOI: 10.3760/cma.j.issn.2096-3076.2017.12.005
• Publication Date: 2017-12-15
• Authors: Qiongying Wang; Qiang Wu; Xu Han; Xiaoqing Kou; Ruixin Ma; Xin Lin; Shougang Sun; Guangli Xu; Xiaowei Zhang; Feng Zhao; Feng Bai
• Keywords: Malondialdehyde; Isovolumic relaxation time

Objective To investigate the effect of exogenous tetrahydrobiopterin (BH4) on improving left ventricular diastolic dysfunction and association with cardiac oxidative stress in spontaneously hypertensive rats (SHR).

Methods 10-week aged specific pathogen free male were divided into 4 groups: Wistar-Kyoto (WKY), WKY + BH4, SHR BH4(with 16 each group). Rats BH4 groups given 200 mg·kg-1·d-1 by lavage administration, while control received same volume sterile water. After one month intervention, hemodynamic echocardiographic parameters used to assess structure function.High performance liquid chromatography analysis was measure biopterins. Myocardial cyclic guanosine monophosphate (cGMP), malondialdehyde (MDA), superoxide dismutase (SOD) nitric oxide (NO) detected ELISA analysis.

Results Compared group, group showed significant hypertrophy, function indexes including peak velocity ratio mitral flow early late phase (E/A), annulus (E/E′) isovolumic relaxation time (IVRT) significantly increased (P<0.05), (E′/A′), propagation (Vp) decreased (P<0.05). BH4adminstration, E/E′ lower SHR+ when compared (all P<0.05). Compared end-systolic pressure (LVESP), end-diastolic (LVEDP), relationship (EDPVR) Tau index higher group. treated had EDPVR than those levels / BH2 NO production (P<0.01) SOD activities higher.

Conclusion Exogenous can improve increasing reducing stress.

Key words: Hypertension; Tetrahydrobiopterin; Ventricular function,