scholarly journals Hypothermic preservation of rat hearts using antifreeze glycoprotein

2020 ◽  
pp. 1029-1038
Author(s):  
Shintaro Takago ◽  
Isao Matsumoto ◽  
Hiroki Kato ◽  
Naoki Saito ◽  
Hideyasu Ueda ◽  
...  

Antifreeze proteins are an effective additive for low-temperature preservation of solid organs. Here, we compared static hypothermic preservation with and without antifreeze glycoprotein (AFGP), followed by nonfreezing cryopreservation of rat hearts. The heart was surgically extracted and immersed in one of the cardioplegia solutions after cardiac arrest. Control rat hearts (n=6) were immersed in University of Wisconsin (UW) solution whereas AFGP-treated hearts (AFGP group) (n=6) were immersed in UW solution containing 500 μg/ml AFGP. After static hypothermic preservation, a Langendorff apparatus was used to reperfuse the coronary arteries with oxygenated Krebs-Henseleit solution. After 30, 60, 90, and 120 min, the heart rate (HR), coronary flow (CF), cardiac contractile force (max dP/dt), and cardiac diastolic force (min dP/dt) were measured. Tissue water content (TWC) and tissue adenosine triphosphate (ATP) levels in the reperfused preserved hearts were also assessed. All the parameters were compared between the control and AFGP groups. Compared with the control group, the AFGP group had significantly (p<0.05) higher values of the following parameters: HR at 60, 90, and 120 min; CF at all four time points; max dP/dt at 90 min; min dP/dt at 90 and 120 min; and tissue ATP levels at 120 min. TWC did not differ significantly between the groups. The higher HR, CF, max dP/dt, min dP/dt, and tissue ATP levels in the AFGP compared with those in control hearts suggested that AFGP conferred superior hemodynamic and metabolic functions. Thus, AFGP might be a useful additive for the static/nonfreezing hypothermic preservation of hearts.

1983 ◽  
Vol 245 (2) ◽  
pp. H183-H188 ◽  
Author(s):  
K. P. Sunnergren ◽  
M. J. Rovetto

Testicular hyaluronidase prevents increased coronary vascular resistance (CVR) during prolonged myocardial ischemia. The mechanism is unknown, but edema and contracture both have been suggested to increase CVR. Additionally, the extent of contracture has been inversely related to ATP levels. Therefore, isolated perfused ischemic rat hearts were treated with hyaluronidase, following a 25% increase in CVR, to determine whether 1) increased CVR was reversed, 2) edema or contracture was reduced, and 3) tissue ATP levels were increased. Three hours of low-flow ischemia decreased coronary flow (CF) from 17.4 +/- 0.13 to 12.6 +/- 0.2 ml X min-1 X g dry tissue-1. During the subsequent 2 h of ischemia, CF of vehicle-treated hearts continued to decline to 8.0 +/- 0.76 ml X min-1 X g dry tissue-1, whereas CF of hyaluronidase-treated hearts increased to 15.6 +/- 1.17 ml X min-1 X g dry tissue-1. These changes in CF persisted during postischemic perfusion. Furthermore, restoration of coronary vascular resistance by hyaluronidase was associated with a 19% reduction in tissue water compared with control ischemic hearts but not with a reduction in cardiac contracture or an increase in tissue ATP. These results suggest that treatment of ischemic hearts with hyaluronidase reverses increased CVR through a reduction in tissue edema.


1996 ◽  
Vol 5 (4) ◽  
pp. 505-511 ◽  
Author(s):  
Yasuyuki Sakai ◽  
Katsutoshi Naruse ◽  
Ikuo Nagashima ◽  
Tetsuichiro Muto ◽  
Motoyuki Suzuki

The feasibility of University of Wisconsin (UW) solution in short-term hypothermic preservation of porcine hepatocyte spheroids was investigated, because they have great potential in bioartificial liver (BAL) systems. Porcine hepatocyte spheroids preserved for 3 days expressed almost comparable levels of albumin secretion as those without preservation, during 8 subsequent days of recultivation in continuous rotational culture, whereas isolated single cells did not reorganize into spheroids and completely lost their function in recultivation. Although for 3-day–preserved spheroids, the albumin secretion was lowered immediately after recultivation (Days 0–2), it was completely restored to that of nonpreserved ones. The function was completely lost in recultivation for 7-day–preserved ones. These results demonstrate that reorganization into spheroids is effective in preventing the functional loss of porcine hepatocytes occurring in hypothermic preservation, and that spheroid formation should precede the preservation as long as spheroid culture is finally used in BAL systems. Also, porcine hepatocyte spheroids are shown to be satisfactory stored in UW solution up to 3 days without significant cellular or functional loss.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yang Shen ◽  
Xiao Yang ◽  
Gaofei Li ◽  
Jiayu Gao ◽  
Ying Liang

AbstractThe alterations in the gut microbiota have been reported to be correlated with the development of depression. The purpose of this study was to investigate the changes of intestinal microbiota in depressed patients after antidepressant treatment. We recruited 30 MDD patients (MDD group) and 30 healthy controls (control group). The MDD group received individualized treatment with escitalopram at a maximum dose of 20 mg/day. After depressive symptoms improved to a HAMD scale score > 50%, a fecal sample was collected again and used as the follow-up group. The differences of gut microbiota between patients and controls, the characteristics of gut microbiota under treatment and the potential differences in metabolic functions were thus investigated. The Firmicutes/Bacteroidetes ratio was significantly different within three groups, and the ratio of follow-up group was significantly lower than those of the other two groups. Alpha diversity was significantly higher in MDD group than those of the other groups, and the alpha diversity was not significantly different between control and follow-up groups. The beta diversity of some patients resembled participants in the control group. The metabolic function of gut microbiota after treatment was still different from that of the control group. This study suggests that the intestinal flora of depressed patients has a tendency to return to normal under escitalopram treatment.


2021 ◽  
Vol 13 ◽  
pp. 251584142110304
Author(s):  
Emre Aydemir ◽  
Alper Halil Bayat ◽  
Burak Ören ◽  
Halil Ibrahim Atesoglu ◽  
Yasin Şakir Göker ◽  
...  

Purpose: The purpose of this study was to compare the retinal vascular caliber of COVID-19 patients with that of healthy subjects. Methods: This was a prospective case–control study. Forty-six patients who had COVID-19 were successfully treated, and 38 age- and gender-matched healthy subjects were enrolled in this study. Fundus photography was taken using fundus fluorescein angiography (FA; Visucam 500; Carl Zeiss Meditec, Jena, Germany). Retinal vascular caliber was analyzed with IVAN, a semi-automated retinal vascular analyzer (Nicole J. Ferrier, College of Engineering, Fundus Photography Reading Center, University of Wisconsin, Madison, WI, USA). Central retinal artery equivalent (CRAE), central retinal vein equivalent (CRVE), and artery–vein ratio (AVR) were compared between groups. Results: The mean age was 37.8 ± 9.5 years in the COVID-19 group ( n = 46) and 40 ± 8 years in the control group ( n = 38) ( p = 0.45). The mean CRAE was 181.56 ± 6.40 in the COVID-19 group and 171.29 ± 15.06 in the control group ( p = 0.006). The mean CRVE was 226.34 ± 23.83 in the COVID-19 group and 210.94 ± 22.22 in the control group ( p = 0.044). AVR was 0.81 ± 0.09 in the COVID-19 group and 0.82 ± 0.13 in the control group ( p = 0.712). Conclusion: Patients who had COVID-19 have vasodilation in the retinal vascular structure after recovery. As they may be at risk of retinal vascular disease, COVID-19 patients must be followed after recovery.


Author(s):  
Edward C. T. Waters ◽  
Friedrich Baark ◽  
Zilin Yu ◽  
Filipa Mota ◽  
Thomas R. Eykyn ◽  
...  

Abstract Purpose To determine the sensitivity of the 18F-radiolabelled dihydroethidine analogue ([18F]DHE) to ROS in a validated ex vivo model of tissue oxidative stress. Procedures The sensitivity of [18F]DHE to various ROS-generating systems was first established in vitro. Then, isolated rat hearts were perfused under constant flow, with contractile function monitored by intraventricular balloon. Cardiac uptake of infused [18F]DHE (50–150 kBq.min−1) was monitored by γ-detection, while ROS generation was invoked by menadione infusion (0, 10, or 50 μm), validated by parallel measures of cardiac oxidative stress. Results [18F]DHE was most sensitive to oxidation by superoxide and hydroxyl radicals. Normalised [18F]DHE uptake was significantly greater in menadione-treated hearts (1.44 ± 0.27) versus control (0.81 ± 0.07) (p < 0.05, n = 4/group), associated with concomitant cardiac contractile dysfunction, glutathione depletion, and PKG1α dimerisation. Conclusion [18F]DHE reports on ROS in a validated model of oxidative stress where perfusion (and tracer delivery) is unlikely to impact its pharmacokinetics.


2020 ◽  
Author(s):  
Yu Tian ◽  
Nan Li ◽  
Wei Wang ◽  
Na Li

Abstract Objective: This study aims to observe the physiological and pathological changes of severed fingers (limbs) under different storage conditions through animal experiments, and to screen out the best preservation conditions. Medthods: Sixty healthy adult male Sprague-Dawley rats were selected and evenly divided into 4 preservation groups, including conventional low-temperature dry (CLTD), the university of wisconsin (UW) solution, cryopreservation and cryopreservation + UW solution preservation group. After harvesting the limbs, were preservated for 72 h and 7 days, respectively. Then the limbs were thawed and replanted in situ. Sciatic nerves were collected for hematoxylin and eosin (HE) staining, and observed the changes in tissue morphology. Results: Replantation was successful in 11 out of 15 rats (73%) in cryopreservation + UW group, and the walking function of the 9 (82%) rats in cryopreservation + UW group were significantly better than that of the cryopreservation preservation group. In addition, the HE staining results shown that the CLTD group nerve bundles were morphologically damaged, and there were more acellular structures and tissue fragments; the UW group nerve bundles were less injured and the perineurium was more complete and orderly; The nerve bundles in the cryopreservation group and cryopreservation + UW group are tightly arranged and the tissue morphology is regular; Compared with the cryopreservation + UW group, the complete of the cryopreservation group is not well. Conclusions: The cryopreservation technology combined with UW solution is a new and effective method for the severed limbs preserving.


2001 ◽  
Vol 281 (3) ◽  
pp. C758-C772 ◽  
Author(s):  
Julia O. Hegge ◽  
James H. Southard ◽  
Robert A. Haworth

Isolated rat myocytes cold stored anaerobically up to 24 h in University of Wisconsin solution lost 95% of their ATP and 100% of their glycogen. They underwent contracture when rewarmed in a Krebs-Henseleit (KH) medium that contained Ca unless Ca addition was delayed. In the latter case, cell function, measured by stimulation-induced cell shortening, was surprisingly well retained. Aerobically stored cells were resistant to Ca on rewarming, although 96% of glycogen was still lost, along with 46% of ATP. Cells that were incubated for 48 h aerobically with the substrates glucose and pyruvate at pH 6.2 retained 77% of their ATP and 59% of their glycogen, with good cell morphology. At pH 6.2, the demand for ATP was only 55% of that at pH 7.4. However, after rewarming, these cells functioned no better than anaerobically stored cells, although their inotropic response to isoproterenol was improved. We conclude that 1) aerobic conditions with substrates at low pH preserve myocyte metabolic reserves well for 48 h, partly by reducing the demand for ATP; 2) rewarming conditions are critical for anaerobically stored cells with metabolic stores that are severely depleted; and 3) unloaded cell function is surprisingly insensitive to a period of severe metabolic deprivation.


1989 ◽  
Vol 66 (4) ◽  
pp. 1715-1721 ◽  
Author(s):  
G. N. Pierce ◽  
P. S. Sekhon ◽  
H. P. Meng ◽  
T. G. Maddaford

Cardiac contractile function is dependent on the integrity and function of the sarcolemmal membrane. Swimming exercise training is known to increase cardiac contractile performance. The purpose of the present study was to examine whether a swimming exercise program would alter sarcolemmal enzyme activity, ion flux, and composition in rat hearts. After approximately 11 wk of exercise training, cardiac myosin and actomyosin Ca2+-adenosinetriphosphatase (ATPase) activity was significantly higher in exercised rat hearts than in sedentary control rat hearts. Glycogen content was increased in plantaris and gastrocnemius muscles from exercised animals as was succinic dehydrogenase activity in gastrocnemius muscle of exercised rats in comparison to sedentary rat preparations. Sarcolemmal vesicles were isolated from hearts of exercise-trained and control rats. Sarcolemmal Na+-K+-ATPase and K+-p-nitrophenylphosphatase activities, Na+-Ca2+ exchange, and passive Ca2+ binding did not differ between the two groups. ATP-dependent Ca2+ uptake and 5′-nucleotidase activity were elevated in the cardiac sarcolemmal vesicles isolated from exercised animals compared with sedentary control rats. Sarcolemmal phospholipid composition was not altered by the exercise training. Our results demonstrate that swimming training in rats does not affect most parameters of cardiac sarcolemmal function or composition. However, the elevated sarcolemmal Ca2+ pump activity in exercised rats may help to reduce intracellular Ca2+ and augment cardiac relaxation rates. The enhanced 5′-nucleotidase activity may stimulate adenosine production, which could affect myocardial blood flow. The present results further our knowledge on the subcellular response of the heart to swimming training in the rat.


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