Altered nano/micro-order elasticity of pulmonary artery smooth muscle cells of patients with idiopathic pulmonary arterial hypertension.
BACKGROUND
Idiopathic pulmonary arterial hypertension (IPAH) is a disease characterized by progressively increased resistance of pulmonary arteries. In this study, we evaluated the mechanical property of single pulmonary artery smooth muscles cells (PASMC) from patients with IPAH and tested whether the PASMC showed abnormal response to a vasodilator by use of an atomic force microscope (AFM).


METHODS
PASMC were isolated and cultured from explanted lungs of 7 patients with IPAH (IPAH-PASMC). Normal vascular specimens from 3 patients with bronchogenic carcinoma were used as normal controls (normal PASMC). The nano/micro-order elasticity of five to ten living PASMC in each sample was measured by parabolic force curves of cantilever deflection/indentation obtained by using an AFM. The elasticity measurements were performed under control conditions and under condition of nitric oxide (NO) treatment (190 and 380 nmol/L).


RESULTS
There was no significant difference between nano/micro-order elasticity of normal PASMC and that of IPAH-PASMC under the control conditions. In normal PASMC, NO (190 and 380 nmol/L) significantly reduced (i.e., softened) the nano/micro-order elasticity. However, NO did not reduce elasticity in IPAH-PASMC, indicating higher vasodilator-resistive nano/micro-order rigidity in IPAH-PASMC.


CONCLUSIONS
Nano/micro-order elasticity change in PASMC in response to vasodilation induced by NO is reduced in patients with IPAH.
Nakamura
Kazufumi
K
Department of Cardiovascular Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan. ichibun@cc.okayama-u.ac.jp
Shimizu
Juichiro
J
Kataoka
Noriyuki
N
Hashimoto
Katsushi
K
Ikeda
Tetsuya
T
Fujio
Hideki
H
Ohta-Ogo
Keiko
K
Ogawa
Aiko
A
Miura
Aya
A
Mohri
Satoshi
S
Nagase
Satoshi
S
Morita
Hiroshi
H
Kusano
Kengo Fukushima
KF
Date
Hiroshi
H
Matsubara
Hiromi
H
Mochizuki
Seiichi
S
Hashimoto
Ken
K
Kajiya
Fumihiko
F
Ohe
Tohru
T
D000293:Adolescent; D000328:Adult; D002478:Cells, Cultured; D002648:Child; D004548:Elasticity; D005260:Female; D016166:Free Radical Scavengers / Q000494:pharmacology*; D006801:Humans; D006976:Hypertension, Pulmonary / Q000473:pathology*; D008297:Male; D018625:Microscopy, Atomic Force; D009119:Muscle Contraction / Q000502:physiology; D032389:Myocytes, Smooth Muscle / Q000187:drug effects / Q000473:pathology*; D049329:Nanostructures; D009569:Nitric Oxide / Q000494:pharmacology; D014665:Vasodilator Agents / Q000494:pharmacology*; D055815:Young Adult
D016166:Free Radical Scavengers; D014665:Vasodilator Agents; D009569:Nitric Oxide