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1.
Rauen U  de Groot H 《Cryobiology》2008,56(1):88-92
Organ preservation solutions have been designed to protect grafts against the injury inflicted by cold ischemia. However, toxicity of University of Wisconsin (UW) solution during rewarming has been reported. Therefore, we here assessed the toxicity of UW, histidine-tryptophan-ketoglutarate (HTK), Euro-Collins, histidine-lactobionate (HL), sodium-lactobionate-sucrose and Celsior solutions in cultured hepatocytes under hypothermic (4 °C), intermediate (21 °C) and physiological (37 °C) conditions. Marked toxicity of UW, HTK, HL and Euro-Collins solutions was observed at both 37 and 21 °C. With the exception of UW solution, these solutions also increased cell injury during cold incubation (LDH release after 18 h at 4 °C: HTK 76 ± 2%, Euro-Collins 78 ± 17%, HL 81 ± 15%; control: Krebs-Henseleit buffer 20 ± 6%). Testing of individual components using modified Krebs-Henseleit buffers suggested that histidine and phosphate are responsible for (part of) this toxicity. These potential toxicities should be taken into account in the development of future preservation solutions.  相似文献   

2.
We previously described the entity of cold-induced apoptosis to rat hepatocytes and characterized its major, iron-dependent pathway. However, after cold incubation in some solutions, e.g. cell culture medium, hepatocytes show an additional, yet uncharacterized component of cold-induced injury. We here assessed the effects of organ preservation solutions on both components of cold-induced injury and tried to further characterize the iron-independent component. None of the preservation solutions (University of Wisconsin, histidine-tryptophan-ketoglutarate, Euro-Collins, histidine-lactobionate, sodium-lactobionate-sucrose and Celsior solutions) provided significant protection against cold-induced cell injury (LDH release after 24-h cold incubation/3h rewarming >65% for all solutions); three solutions even enhanced cold-induced injury. However, when the predominant iron-dependent mechanism was eliminated by the addition of iron chelators, all preservation solutions yielded hepatocyte protection that was clearly superior to the one obtainable in cell culture medium or Krebs-Henseleit buffer with iron chelators (LDH release after 24-h cold incubation/3h rewarming 相似文献   

3.
Summary Rat liver parenchymal cells were isolated by EDTA perfusion and were subsequently purified by Percoll centrifugation. The freshly isolated liver cells had a mean viability of 95% as judged by trypan blue exclusion. Isolated liver parenchymal cells were then stored at 0°C for up to 1 wk in University of Wisconsin solution (UW). During this hypothermic preservation, the viability was only slightly reduced to 92% after 1 d and to 85% after 3 d at 0°C. Thereafter, the viability decreased rapidly. After cold storage for up to 3 d, it was possible to use the parenchymal liver cells either in short-term suspension or in cell culture. The attachment efficiency in cell culture was the same for freshly isolated liver cells (84%) and after 2 d cold preservation (81%). The cytochrome P450 content and the enzyme activities of soluble expoxide hydrolase, UDP-glucuronosyl transferase, phenol sulfotransferase, and glutathione S-transferase were not significantly different between freshly isolated cells and cells after 3 d of hypothermic preservation. Furthermore, freshly isolated and intact liver cells stored for 3 d were used in the cell-mediated Salmonella mutagenicity test as a metabolizing system. Both fresh and stored liver parenchymal cells metabolized benzo(a)pyrene, 2-aminoanthracene, and cyclophosphamide to their ultimate mutagens. Thus, it was clearly demonstrated that EDTA-isolated liver parenchymal cells retain their xenobiotic metabolizing capacity after short-term hypothermic preservation for up to several days and, therefore, may help to maximize the usefulness of rarely available liver parenchymal cells such as those from humans and help to reduce the number of experimental animals required for pharmacological and toxicologicalin vitro investigations.  相似文献   

4.

Introduction

Endothelial barrier function is pivotal for the outcome of organ transplantation. Since hypothermic preservation (gold standard) is associated with cold-induced endothelial damage, endothelial barrier function may benefit from organ preservation at warmer temperatures. We therefore assessed endothelial barrier integrity and viability as function of preservation temperature and perfusion solution, and hypothesized that endothelial cell preservation at subnormothermic conditions using metabolism-supporting solutions constitute optimal preservation conditions.Methods: Human umbilical vein endothelial cells (HUVEC) were preserved at 4–37 °C for up to 20 h using Ringer's lactate, histidine–tryptophan–ketoglutarate solution, University of Wisconsin (UW) solution, Polysol, or endothelial cell growth medium (ECGM). Following preservation, the monolayer integrity, metabolic capacity, and ATP content were determined as positive parameters of endothelial cell viability. As negative parameters, apoptosis, necrosis, and cell activation were assayed. A viability index was devised on the basis of these parameters.Results: HUVEC viability and barrier integrity was compromised at 4 °C regardless of the preservation solution. At temperatures above 20 °C, the cells' metabolic demands outweighed the preservation solutions' supporting capacity. Only UW maintained HUVEC viability up to 20 °C. Despite high intracellular ATP content, none of the solutions were capable of sufficiently preserving HUVEC above 20 °C except for ECGM.Conclusion: Optimal HUVEC preservation is achieved with UW up to 20 °C. Only ECGM maintains HUVEC viability at temperatures above 20 °C.  相似文献   

5.
We very recently showed (using a blood-free perfusion model) that cold preservation sensitized rat hepatocyte functions to rewarming ischemic injury and that the injury can be prevented by repleting high-energy adenylates in the liver by short-term oxygenated warm reperfusion. Here we investigated whether short-term reperfusion after the preservation period can improve hepatic graft function in a blood reperfusion model. Eighteen-hour cold-preserved rat livers either untreated (Group A) or pretreated by 30-min oxygenated warm reperfusion after preservation (Group B) were subjected to 20-min ischemic rewarming and then reperfused with blood. Livers in Group B compared to Group A exhibited approx. three times increased bile production and bromosulfophthalein excretion, nearly 7-fold decreased swelling, and 1.2-fold improved blood flow. These results suggest that repletion of the energy by short-term oxygenated reperfusion after prolonged preservation may improve markedly initial hepatic graft function.  相似文献   

6.
Post-transplantation thrombosis may occur in donor segments of iliac arteries and livers following surgical removal and storage in University of Wisconsin (UW) solution for transplantation. We have previously suggested that purine receptors are vulnerable to denaturation after UW storage. The aims of the present study were to determine what particular subtypes of purine P2Y receptors in rabbit thoracic aorta deteriorate after 8 days of UW storage by studying vascular reactivity to acetylcholine, ATP, 2MeSATP and UTP. Ring segments of aortae from male New Zealand White rabbits were mounted upon fine-wire myographs and vasodilatation to the above agents tested on fresh tissue, and after 8 days of UW storage. Vasodilatation to ATP was attenuated by 100 microM L-NAME in fresh tissue suggesting that the relaxant response was, in part, due to nitric oxide (NO). P2Y-mediated relaxation to ATP was significantly attenuated by UW storage and cholinergic responses were not. This attenuated relaxation to ATP was not further attenuated by L-NAME, suggesting a loss of the NO-dependent mechanism. De-endothelialisation indicated that UTP-mediated vasorelaxation, via P2Y(2) receptors, was endothelium-dependent. Any residual endothelium-independent relaxation to UTP was abolished by UW storage and endothelium-dependent UTP relaxation was reduced to the same level as that seen in fresh, de-endothelialised tissue. In contrast responses to 2MeSATP, via P2Y(1) receptors, were predominantly endothelium-independent and were only partially attenuated by UW storage. Responses to pyridoxalphosphate-6-azophenyl-2('),4(')-disulphonic acid (PPADS) and L-NAME suggested that vasorelaxation to 2MeSATP and UTP was mediated by P2Y(1) and P2Y(2) receptors, respectively. It is therefore concluded that UW storage predominantly decreases P2Y(2) receptor-mediated vascular reactivity.  相似文献   

7.
Urea cycle (UC) is the main pathway of ammonium removal. A deficiency in any of the five classical enzymes of the pathway causes a urea cycle disorder. Hepatocellular transplantation is one of the techniques applicable to treat this disorder. In the present work, we investigated the activities and the relative expression levels of two of the UC enzymes: Carbamyl phosphate synthetase I (CPSI) and ornithine transcarbamylase (OTC), in isolated hepatocytes preserved up to 120 h in University of Wisconsin (UW) solution at 0 degrees C, and during the rewarming of these suspensions. During preservation, CPSI showed differences in mRNA levels respect to time 0, while ornithine transcarbamylase remained unchanged. At the end of the rewarming, CPSI showed values of enzymatic activity and relative mRNA level comparable with the control, meanwhile, there was an increment in OTC activity. In line with these results, we found that hepatocytes cold preserved up to 120h in UW solution maintained their ability to remove an ammonium load comparable to freshly isolated hepatocytes. These data indicated that our preservation conditions up to 120h in UW solution followed by rewarming, preserves UC enzymes at levels similar to freshly isolated hepatocytes, allowing the use of these cells in bioartificial liver devices or hepatocellular transplantation.  相似文献   

8.
Preservation with University of Wisconsin (UW) solution has been implicated in coronary artery endothelial damage and loss of endothelium-dependent vasodilatation. Therefore, the objective of this study was to investigate the effect of this solution on basal nitric oxide (NO) release from porcine coronary endothelial cells (CEC). Cultures were exposed to cold (4 degrees C) storage in UW solution for 6, 8 and 12 h. Parallel cultures were incubated with control medium at 37 degrees C. After treatment, NO release was evaluated by nitrite production, a stable metabolite of NO. Activity of the constitutive endothelial nitric oxide synthase (eNOS) was measured by the conversion [3H]-l-arginine to [3H]-l-citrulline and eNOS protein expression by Western blotting. Nitrite production by control cells was augmented with increasing times of incubation, whereas no change was observed in those cultures preserved with UW solution. Activity of eNOS was significantly decreased compared to the respective control group by cold storage of cells for longer periods than 6 h. Such decrease was correlated with a diminished eNOS protein expression in CEC preserved with UW solution after 8- and 12-h storage. These results suggest that prolonged hypothermic storage of CEC with UW solution does not preserve basal NO release because of a certain loss of eNOS protein, which may contribute to the reported injury of heart transplants after long-term preservation.  相似文献   

9.
10.
The effect on tissue differentiation and growth in vitro of certain of the factors implicated in collagen synthesis (ascorbic acid, α-ketoglutarate and oxygen) and the influence of hydrocortisone was studied using organ cultures of fetal mouse mandible as a mixed epithelial and connective tissue system. Using serum-free Waymouth’s MB 752/1 chemically-defined medium, addition of high levels of ascorbic acid (300 μg per ml), hydrocortisone (1 μg per ml) and oxygen (95%) enhanced differentiation in a number of tissues, in particular skin and appendages, tooth germs and bone, while osteoid and dentine production were noticeably promoted. It is suggested that an essential aspect of media design for organ culture involves the incorporation of collagen-promoting factors to the in vitro environment particularly with regard to the controlling role implicated for collagen in a variety of biological processes. Some of the work reported here was undertaken while A. H. Melcher was a member of the Department of Dental Science, Royal College of Surgeons of England, London, England.  相似文献   

11.
The goals of this research were two. A first aim was to determine relationships between craniofacial anatomy and craniofacial response to cold, and a second, to apply the results to historical and evolutionary models. Detailed anthropometric measurements were taken on 58 young men native to Hawaii; 33 were of Japanese descent, and 25 of European ancestry. Facial and other temperatures were recorded during 70 minutes of cooling at 0°C. Heat loss was enhanced by ten foot-per-second air movement. Though the Europeans showed more cold-induced vasodilation at facial sites, there were cross-sample correlation agreements which suggested that temperatures remain lower in the presence of high cheek thickness, protrusive malar area, and probably a smaller, shorter head. Consequently, the Coon-Garn-Birdsell “cold-engineered face,” based on a frostbite selection model, is rejected, and an effort is made to fit Asiatics, Europeans and European Neanderthals to current findings. Additional detail is presented on shape-temperature regressions as well as simple racial comparisons for cranio-facial shape, body build, and temperature.  相似文献   

12.
Summary In the present study we sought to determine the developmental potentialities and restrictions of adrenal medullary cells (pheochromoblasts) by investigating their morphological and biochemical response to nerve growth factor (NGF), anti-NGF antibodies and dexamethasone (DEX) after explantation into culture at different embryonic stages. With the exception of explants taken at embryonic day 15 (E 15) cultures of embryonic adrenal glands showed neurite outgrowth, which was not influenced by the addition of NGF, anti-NGF antibodies or DEX to the culture medium during the 4-day-culture period.Pheochromoblasts in E 17+4 explants showed spontaneous ultramorphological and biochemical maturation in terms of an increase in the number of catecholamine storage vesicles (CSVs) per m2 of cytoplasmic area, diameters of the cores of CSVs, percentages of electron-lucent cores of CSVs indicative of increased storage of adrenaline, overall catecholamine (CA) content and relative amount of adrenaline. NGF did not significantly affect this maturational process. Anti-NGF antibodies slightly decreased the proportion of adrenaline. The most pronounced maturation was seen in response to DEX and DEX plus NGF, although a maturational state equivalent to the E 21 stage was not achieved. E 21+4 explants showed neither spontaneous nor drug-induced biochemical maturation. Medullary cells in NGF-treated E 21 explants frequently retained the morphological features of pheochromoblasts. Treatment with anti-NGF antibodies significantly reduced the portion of adrenaline as compared to any other treatment. We conclude that under the culture conditions employed (1) a few pheochromoblasts spontaneously express a neuronal phenotype, (2) differentiation of pheochromoblasts towards chromaffin cells is enhanced by glucocorticoids but not by NGF, and (3) anti-NGF antibodies do not impair spontaneous neuritic growth and morphological maturation of pheochromoblasts, but cause a small reduction in the relative amount of adrenaline.  相似文献   

13.
The major goal of hypothermic (4–8 °C) preservation of intact pancreases or isolated islets will be to provide sufficient time for HLA typing, cross matching, selection, and preparation of recipients—logistical efforts requiring 12–72 hr for clinical kidney transplantation, usually <48 hours. Some investigators have studied in vitro function of islets after cold storage, but the critical test of viability—permanent restoration of normoglycemia after transplantation to diabetic recipients—has been tested in only a few experiments. Reversal of hyperglycemia by syngeneic or autogenic transplants in diabetic animals has been achieved after CS of dispersed pancreatic tissue from neonatal rats in GIB media for ? 146 hr, adult dogs in TCM 199 for ?24 hr, and adult DL-ethionine-treated rats in RPMI 1640 for ?72 hr. In the neonatal rat donor model, intravenous glucose tolerance test (IVGTT) results were similar in recipients of fresh or stored islets; in the dog model, IVGTT test results were variable, but generally inferior in recipients of stored as compared to fresh islets; in the adult rat donor model, recipients of ?24-hr coldstorage islets had insulin and IVGTT K values similar to those of recipients of fresh islets, but the success rate progressively declined for CS times >24 hr. Various agents were added to the media, but the need or the optimal concentrations were not critically determined by using different recipes for different groups of recipients. Cold storage of intact pancreas autografts has been tested in dogs; simple electrolyte solutions are satisfactory for 24 hr, but only a silica gel-filtered plasma-based solution has been reliable for 48 hr. Pulsatile machine perfusion (PMP) of canine pancreas grafts for 24 hr has had a success rate similar to CS in some experiments and lower in others. PMP has been almost totally unreliable for >24 hr. Further refinements are needed if preservation of islets for >24 hr and pancreases for >48 hr are to be consistently successful. If current experimental techniques are effective for human islets or pancreases, however, these times are sufficient to complete the logistical maneuvers required before transplantation.  相似文献   

14.
Performance of major components of maternal care was evaluated quantitatively in several test situations for various groups of rats. Maternal behavior of concaveated ovaríectomized virgin females and castrated males was inferior on a variety of measures to that of concaveated intact virgin females. However, concaveated intact virgin females were markedly inferior to natural mothers on measures of nest building and responsiveness to an intruder. Thus, it was found that test situations other than the standard homecage test revealed previously undetected group differences and that the occurrence of pup retrieval is not a valid predictor of the performance of some major components of maternal care. In addition, it was concluded that gonadal hormones partially determine the quality of maternal responsiveness displayed by virgin females, but that gonadal hormones characteristic of the cycling female are not sufficient to increase maternal responsiveness to the level seen with natural mothers. Possible relationships between pup-induced maternal behavior and that of natural mothers are discussed.  相似文献   

15.
Summary Mevinolin, an inhibitor of cholesterol synthesis, was used to study the effect of endogenous cholesterol synthesis on the morphology and function of differentiating and differentiated fetal rat adrenocortical cells grown in primary culture. Upon adrenocorticotrophic hormone (ACTH) stimulation under conditions in which endogenous cholesterol synthesis was inhibited but exogenous (lipoprotein) cholesterol was available, the cells differentiated normally from glomerulosa-like to fasciculata-like cells; the steroid hormone secretion was maximally induced. Under conditions in which cholesterol synthesis was maximally inhibited by mevinolin and the cells had no access to exogenous cholesterol, the cells did not differentiate into fasciculata-like cells; the ACTH-induced steroid response was highly suppressed under these conditions. The addition of either human low-density lipoprotein (LDL) or high-density lipoprotein (HDL3) to the culture medium restored the ACTH-induced differentiation and steroid secretion. Thus, in the absence of exogenous cholesterol, endogenous cholesterol synthesis was a prerequisite for differentiation. In cultures grown in the presence of exogenous cholesterol and ACTH with mevinolin-inhibited cholesterol synthesis and high steroid output, an increase in cytoplasmic lipids was evident, suggesting upregulation of LDL and HDL receptors. The results also demonstrated that induction of phenotypic differentiation from glomerulosalike into fasciculata-like cells can proceed in the presence of a cholesterol synthesis inhibitor like mevinolin; this differentiation in the absence of endogenous cholesterol synthesis is accompanied by the appearance of cytoplasmic cholesterol ester droplets, typical of fasciculata cells.  相似文献   

16.
Parenchymal cells from normal adult rat liver, prepared with high yield (30 × 106 cells/g liver) and viability index (>96%) by a non-perfusion method, were maintained in non-proliferating monolayer culture. Several metabolic functions were investigated for 7 days to evaluate functional integrity of the cultured hepatocytes. Leucine was linearly incorporated into protein for 4.5 h at each day of cultivation and the incorporation rate increased up to 2-fold after 3 days. Urea production was maintained at a rate of 0.5 μmoles/mg protein × h for at least 7 days, and its amount was enhanced 2-fold within 24 h by the addition of 3 mM NH4Cl. Glucose was formed during the first days by the hepatocytes and was then taken up with increasing amount from the surrounding medium. Lactate consumption, on the other hand, was replaced by lactate production after one day of cultivation.Variations in enzyme levels of lactate dehydrogenase, arginase, glutamine synthetase and glucose-6-phosphatase were also studied during the whole culture period. Cell leakage, which was detected only in the case of lactate dehydrogenase (LDH), occurred through the 4th day along with a concomitant loss of intracellular LDH activity. After 4 days, however, the enzyme activity returned to the initial level. Arginase was maintained throughout the cultivation period and was stimulated 2- to 3-fold within 24 h by NH4Cl. Glutamine synthetase declined within the first 4 h of cultivation and then remained in the hepatocytes with a transitory rise after 2 days. Its activity was also found to be inversely related to the concentration of glutamine in the culture medium up to 4 mM. Glucose-6-phosphatase gradually decreased during the cultivation period, the enzyme activity, however, was stimulated by glucagon within 24 h.  相似文献   

17.
Abstract The occurrence of microbodies in different cells of the nematophagous fungus Arthrobotrys oligospora has been investigated. In the predacious phase this organism forms complex 3-dimensional network traps. Mature trap cells generally were crowded with "special" microbodies which possessed an electron dense matrix and were surrounded by a membrane of approx. 9 nm. These organelles developed during the early stages of trap formation and were derived from specialized regions of the endoplasmic reticulum. Cytochemical staining experiments revealed that the electron-dense microbodies contained catalase and d -amino acid oxidase and thus must be considered peroxisomal in nature. Electron-dense bodies were absent in normal vegetative cells of the fungus. These cells contained "normal" microbodies which developed from each other by the separation of small organelles from mature ones. As in yeasts, the metabolic function of these latter organelles was dependent upon environmental conditions.  相似文献   

18.
Hormonal control of flower induction and inflorescence development in vitro was investigated in Spathiphyllum. The effects of gibberellic acid (GA3) and sucrose on inflorescence development were studied in plantlets regenerated in tissue culture. GA3 was mandatory for the shift from the vegetative to the reproductive stage. The effect of sucrose concentration on inflorescence bud development was studied in plantlets cultured in MS medium supplemented with 10 mg l−1 GA3. Sucrose concentration at 3 or 6% induced inflorescence development in, respectively, 83–85% of the plantlets. The effect of GA3 and sucrose on inflorescence differentiation and development were also recorded in liquid culture using air-lift bioreactor. The best response was found in the same medium which was standardized as an optimum for solid culture, but the results were better than solid culture. In order to study the relationship between glutathione (GSH) and flowering, we also measured the oxidized and reduced GSH content in leaves throughout the culture period on 2 weeks interval. The GSH accumulation was more after 4 weeks until 6 weeks in GA3 treated plantlets. Similarly, glutathione reductase which is involved in the recycling of reduced GSH providing a constant intracellular level of GSH, was also higher in GA3 treated plantlets. The transient increase in GSH contents also correlated with the changes in measured γ-glutamylcysteine synthetase (γ-ECS) activity over the same period. The antioxidant enzyme activity in GA3 treated plantlets also suggests that the plants suffered increased oxidative stress during the period of GA3 treatment which subsequently increases GSH synthesis through activation of γ-ECS and this promotes flowering by increasing endogenous GSH.  相似文献   

19.
目的:探索成年大鼠阴茎海绵体内cajal间质细胞(ICCs)的分离、培养和鉴定方法,为进一步研究其在阴茎海绵体中的作用提供条件.方法:取大鼠阴茎海绵体组织,采用酶消化法分离细胞,差速贴壁法相对纯化ICCs,将纯化后的细胞悬液接种于DMEM培养基中进行培养.通过倒置显微镜下观察细胞贴壁和形态,并用c-Kit特异性抗体标记细胞,免疫荧光法鉴定ICCs.结果:培养24小时后ICCs贴壁良好,细胞形态学观察显示ICCs呈纺锤状,有两个或多的突起,免疫荧光检验可见ICCs呈c-Kit抗体染色阳性.结果:用酶消化法可成功分离和培养大鼠阴茎海绵体ICCs,大鼠海绵体组织内ICCs的生理学功能有待进一步研究.  相似文献   

20.
The role of dietary Cu and Mn in maintaining tissue integrity, through the effects of these metals on activity of the superoxide dismutase (SOD) enzyme, and their interactions in peroxidative pathways involving Se and vitamin E was investigated. Weanling rats were fed diets deficient in Mn, Cu, Se, and/or vitamin E for 35 days, in a factorial experimental design. Dietary effects on peroxidation, measured in mitochondrial fractions prepared from liver and heart tissue, were compared with changes in the activities of glutathione peroxidase and the Cu and MnSOD enzymes. Decreased heart MnSOD and CuSOD activities, resulting from dietary Mn and Cu deficiencies, were both associated with increased peroxidation. Adequate Se (and glutathione peroxidase activity) prevented the peroxidation associated with either of these deficiencies, but was ineffective with a combined Cu−Mn deficiency. These effects of Se were only observed in tissue lacking glutathione transferase activity. Effects of Cu, Mn, and Se on peroxidation appeared to be present at both levels of vitamin E, although in both tissues, vitamin E deficiency greatly increased the overall peroxidation. Comparison of these in vitro peroxidation results with the deficiency associated lesions observed in vivo indicates that changes in SOD activities and peroxidation pathways may be the dominant cause of these lesions in only some cases. In others, the roles of Cu and Mn in different metabolic pathways appear to be of greater importance.  相似文献   

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