1. Percutaneous Carbon Dioxide Gas Mist Ameliorates Cardiac Remodeling
after Myocardial Infarction in Rats
＊ : p<0.05
(ms1/2)
T. Yamazaki, Y. Nakamura, Y. Izumi, A. Hanatani, K. Shimada, T. Muro, M. Yoshiyama – Osaka City University, Osaka, Japan
<Echocardiography>
Background
Results
<Vasodilatation effect of CO2 gas mist for microvessels >
Pre
10 min
Post 10 min
Re try 5 min
Carbon dioxide (CO2) bathing has been used to treat some cardiac diseases.
P<0.05
P<0.05
P<0.05 * *
The effect of CO2-enriched water on cutaneous circulation depends primarily on the vasodilatation effects elicited by the CO2 that diffuses into the subcutaneous tissue through the skin layers. * * * * *
(Ito T et al. J Invest Dermatol. 1989;93: )
(Schnizer W et al. Int J Microcirc Clin Exp. 1985;4: )
Immersion of an ischemic hind limb into CO2-enriched water caused a nitric oxide (NO)-dependent increase in collateral blood perfusion.
(Irie H et al. Circulation. 2005;111: ) * *
P<0.05
However, the effect of CO2 gas mist has not been examined.
P<0.05 * *
Purpose
<Oxygenated and Deoxygenated Hemoglobin>
<Δ Tissue pH> *
We investigated
1) whether percutaneous CO2 gas mist had useful effects compared with CO2 gas,
2) whether percutaneous CO2 gas mist prevented cardiac remodeling after myocardial infarction (MI) in rats. * * * *
CO2 mist
LVEDV : Left Ventricular End-Diastolic Volume, LVESV : Left Ventricular End-Systolic Volume, LVEF : Left Ventricular Ejection Fraction
* p<0.05 vs NM
<mRNA expressions (pRT-PCR) >
<Serum Concentrations>
Methods
＜MI production＞
MI was induced by ligation of the coronary artery in 8 wks old male Wistar rats.
＜Study Protocol＞
( NM : no CO2 gas mist therapy )
( M+L : 100% CO2 gas mist therapy 30min/day + L-NAME 10 mg/kg/day)
( CM : 100% CO2 gas mist therapy 30 min/day )
( CG : 100% CO2 gas therapy 30 min/day )
( C : Control )
Sacrifice at 4 weeks
Sham operation
MI production
CO2 gas
P<0.05
P<0.05 * *
(min)
(min)
(min)
* p<0.05 vs CO2 gas
<Hemodynamics> *
P<0.05
* p<0.05 vs NM
For normalization, transcript levels were compared to GAPDH.
* p<0.05 vs NM
Summary
CM group had significantly increased oxygenated hemoglobin levels and significantly decreased deoxygenated hemoglobin levels and subcutaneous tissue pH, compared with CG group.
CM group had a significantly increased LVEF compared with NM group.
The CM group had significantly increased NO3- concentrations and cardiac VEGF mRNA expression compared with NM group.
These improvements were significantly abolished with L-NAME treatment.
Our present study shows for the first time that percutaneous CO2 gas mist can prevent cardiac remodeling after MI.
( a nitric oxide synthase inhibitor)
CO2 gas
H2O
CO2 gas mist
CO2 + H2O * * *
Conclusion
The CO2 gas mist was generated using a dry mist production unit.
(Advance Biotron Co., Ltd., Tokyo, Japan)
Percutaneous CO2 gas mist may be a potentially useful therapy for heart failure due to MI.
HR : Heart Rate, sBP : systolic Blood Pressure, dBP : diastolic Blood Pressure, HW : Heart Weight
* p<0.05 vs NM