Improvement of myocardial contractility by trifluoperazine, a calmodulin antagonist, after acute long term cold storage

2010 ◽  
Vol 58 (S 01) ◽  
Author(s):  
I Karliova ◽  
K Denk ◽  
L Hakami ◽  
A Abugameh ◽  
P Ewald ◽  
...  
2006 ◽  
Vol 54 (11) ◽  
pp. 3887-3895 ◽  
Author(s):  
Da-Peng Li ◽  
Yun-Feng Xu ◽  
Li-Ping Sun ◽  
Li-Xia Liu ◽  
Xiao-Li Hu ◽  
...  

Antioxidants ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 403 ◽  
Author(s):  
Celia Vincent ◽  
Tania Mesa ◽  
Sergi Munne-Bosch

(1) Background: Tocochromanols are a group of fat-soluble compounds including vitamin E (tocopherols and tocotrienols) and plastochromanol-8, and just one avocado can contain up to 20% of the required vitamin E daily intake. (2) Methods: HPLC and LC-MS/MS analyses were performed in avocados of various varieties and origin for the identification and quantification of tocopherols, tocotrienols and plastochromanol-8. After selection of the variety with the highest vitamin E content, we evaluated to what extent short- (4 h) and long-term (10 d) cold storage influences the accumulation of tocochromanols. (3) Results: Analyses revealed that “Bacon” avocados (Persea americana Mill. cv. Bacon) were the richest in vitamin E compared to other avocado varieties (including the highly commercialized Hass variety), and they not only accumulated tocopherols (with 110 µg of α-tocopherol per g dry matter), but also tocotrienols (mostly in the form of γ-tocotrienol, with 3 µg per g dry matter) and plastochromanol-8 (4.5 µg per g dry matter). While short-term cold shock did not negatively influence α-tocopherol contents, it increased those of γ-tocopherol, γ-tocotrienol, and plastochromanol-8 and decreased those of δ-tocotrienol. Furthermore, storage of Bacon avocados for 10 d led to a 20% decrease in the contents of α-tocopherol, whereas the contents of other tocopherols, tocotrienols and plastochromanol-8 were not affected. (4) Conclusions: It is concluded that Bacon avocados (i) are very rich in α-tocopherol, (ii) not only contain tocopherols, but also tocotrienols and plastochromanol-8, and (iii) their nutritional vitamin E value is negatively influenced by long-term cold storage.


1997 ◽  
Vol 272 (3) ◽  
pp. H1196-H1204 ◽  
Author(s):  
V. A. Browne ◽  
V. M. Stiffel ◽  
W. J. Pearce ◽  
L. D. Longo ◽  
R. D. Gilbert

We studied myocardial contractility in fetal sheep from ewes exposed to approximately 112 days of hypoxia at high altitude (3,820 m). We measured the inotropic response to extracellular Ca2+ concentration ([Ca2+]o, 0.2-10 mM) and ryanodine (10(-10) to 10(-4) M) in isometrically contracting papillary muscles and quantified dihydropyridine (DHPR) and ryanodine (RyR) receptors. In hypoxic fetuses, curves describing the force-[Ca2+]o relationship were shifted left, and the top plateaus were decreased by approximately 35% in both left and right ventricles. In normoxic and hypoxic fetuses, ryanodine (10(-4) M) reduced maximum active tension (Tmax) to approximately 25-40% of baseline values, indicating that the sarcoplasmic reticulum was the chief source of activator Ca2+ and that Ca2+ influx alone was not sufficient to activate a contraction of normal amplitude. Hypoxia resulted in a lower Tmax in the right ventricle and a lower maximum rate of rise in the left ventricle after treatment with ryanodine. DHPR number did not change, but RyR number and the RyR/DHPR in both ventricles were higher in hypoxic fetuses. We conclude that hypoxia decreases contractility, possibly by reducing the availability of activator Ca2+. Further studies are needed to directly measure the Ca2+ current and intracellular Ca2+ transient and to examine myofilament protein and adenosinetriphosphatase activity.


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