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Maxová H, Bačáková L, Lisá V, Novotná J, Tomášová H, Vízek M, Herget J. Production of proteolytic enzymes in mast cells, fibroblasts, vascular smooth muscle and endothelial cells cultivated under normoxic or hypoxic conditions. Physiol Res 2010; 59:711-719. [PMID: 20406036 DOI: 10.33549/physiolres.931909] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Matrix metalloproteinases (MMPs) is a family of proteolytic enzymes involved in remodeling of extracellular matrix. Although proteolytic enzymes are produced by many cell types, mast cells seem to be more important than other types in remodeling of pulmonary arteries during hypoxia. Therefore, we tested in vitro production of MMPs and serine proteases in four cell types (mast cells, fibroblasts, vascular smooth muscle cells and endothelial cells) cultivated for 48 h under normoxic or hypoxic (3% O2) conditions. MMP-13 was visualized by immunohistochemistry, MMP-2 and MMP-9 were detected by zymography in cell lysates. Enzymatic activities (MMPs, tryptase and chymase) were estimated in the cultivation media. Hypoxia had a minimal effect on total MMP activity in the cultivation media of all types of cells, but immunofluorescence revealed higher intensity of MMP-13 in the cells exposed to hypoxia except of fibroblasts. Tryptase activity was three times higher and chymase activity twice higher in mast cells cultivated in hypoxia than in those cultured in normoxia. Among all cell types studied here, mast cells are the most abundant source of proteolytic enzymes under normoxic and hypoxic conditions. Moreover, in these cells hypoxia increases the production of both specific serine proteases tryptase and chymase, which can act as MMPs activators.
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Snorek M, Neckar J, Wilhelm J, Skoumalova A, Hodyc D, Sedivy V, Tousek F, Kolar F, Herget J. Acute Caloric Restriction is Cardioprotective in Adult Rats. FASEB J 2010. [DOI: 10.1096/fasebj.24.1_supplement.lb535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Chovanec M, Novotná J, Wilhelm J, Hampl V, Vízek M, Herget J. Hypercapnia attenuates hypoxic pulmonary hypertension by inhibiting lung radical injury. Physiol Res 2010; 58 Suppl 2:S79-S86. [PMID: 20131939 DOI: 10.33549/physiolres.931923] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Chronic lung hypoxia results in hypoxic pulmonary hypertension. Concomitant chronic hypercapnia partly inhibits the effect of hypoxia on pulmonary vasculature. Adult male rats exposed to 3 weeks hypoxia (Fi(02)=0.1) combined with hypercapnia (Fi(C02)=0.04-0.05) had lower pulmonary arterial blood pressure, increased weight of the right heart ventricle, and less pronounced structural remodeling of the peripheral pulmonary arteries compared with rats exposed only to chronic hypoxia (Fi(02)=0.1). According to our hypothesis, hypoxic pulmonary hypertension is triggered by hypoxic injury to the walls of the peripheral pulmonary arteries. Hypercapnia inhibits release of both oxygen radicals and nitric oxide at the beginning of exposure to the hypoxic environment. The plasma concentration of nitrotyrosine, the marker of peroxynitrite activity, is lower in hypoxic rats exposed to hypercapnia than in those exposed to hypoxia alone. Hypercapnia blunts hypoxia-induced collagenolysis in the walls of prealveolar pulmonary arteries. We conclude that hypercapnia inhibits the development of hypoxic pulmonary hypertension by the inhibition of radical injury to the walls of peripheral pulmonary arteries.
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Maxová H, Vasiľková M, Novotná J, Vajnerová O, Baňsová A, Vízek M, Herget J. Prevention of Mast Cell Degranulation by Disodium Cromoglycate Delayed the Regression of Hypoxic Pulmonary Hypertension in Rats. Respiration 2010; 80:335-9. [DOI: 10.1159/000312403] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2009] [Accepted: 02/09/2010] [Indexed: 11/19/2022] Open
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Maxová H, Bačáková L, Eckhardt A, Mikšík I, Lisá V, Novotná J, Herget J. Growth of Vascular Smooth Muscle Cells on Collagen I Exposed to RBL-2H3 Mastocytoma Cells. Cell Physiol Biochem 2010; 25:615-22. [DOI: 10.1159/000315080] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/04/2010] [Indexed: 11/19/2022] Open
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Gálvez Y, Škába R, Vajtrová R, Frantlová A, Herget J. Evidence of Secondary Neuronal Intestinal Dysplasia in a Rat Model of Chronic Intestinal Obstruction. J INVEST SURG 2009; 17:31-39. [DOI: 10.1080/ivs.17.1.31.39] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Chovanec M, Hnilickova O, Smolkova P, Herget J. Superoxide – NO interaction plays an important role in inhibition of hypoxic pulmonary hypertension by hypercapnia. FASEB J 2009. [DOI: 10.1096/fasebj.23.1_supplement.770.8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Rygl M, Novotna J, Herget J, Skaba R, Snajdauf J. Parameters of healing in approximative intestinal anastomosis. Eur J Pediatr Surg 2009; 19:25-9. [PMID: 19221949 DOI: 10.1055/s-2008-1039010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
INTRODUCTION The restoration of bowel continuity using multiple classic anastomoses is mostly impossible in unstable critically ill extremely low birth weight neonates. The parameters of healing of approximative anastomoses in which integrity and continuity of bowel is achieved with limited number of stitches were evaluated in an experimental study. MATERIAL AND METHODS Small bowel anastomoses were performed in twenty-two adult male rats. An approximative ileo-ileal anastomosis was performed with five seromuscular-interrupted sutures only; in the control group the anastomosis was performed with the conventional technique of interrupted sutures. The mechanical and biochemical parameters were compared. RESULTS All anastomoses in both groups healed well without obstruction. The mean operating time needed for an approximative anastomosis was shorter (16 +/- 7.1 min versus 23.6 +/- 6.2 min, p = 0.016). The strength of the approximative anastomoses on the 1st day after surgery was 55 +/- 15 torr; the strength of the conventional anastomoses was 55 +/- 42 torr. The strength of the approximative anastomoses after 7 days was 249 +/- 39 torr; the strength of the conventional anastomoses was 218 +/- 23 torr (p = 0.118). The activity of the collagenolytic enzymes matrix metalloproteinase-2 and matrix metalloproteinase-9 in the anastomotic area was significantly increased compared with the activity in samples of non-operated bowel. There was no significant difference in collagenolytic activity between both types of anastomoses. CONCLUSION The approximative anastomosis is a time-saving alternative to conventional anastomoses with a comparable course of anastomotic healing, anastomotic strength, and changes in collagen metabolism.
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Joshi S, Sedivy V, Hodyc D, Herget J, Gurney AM. KCNQ modulators reveal a key role for KCNQ potassium channels in regulating the tone of rat pulmonary artery smooth muscle. J Pharmacol Exp Ther 2009; 329:368-76. [PMID: 19151245 DOI: 10.1124/jpet.108.147785] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Potassium channels are central to the regulation of pulmonary vascular tone. The smooth muscle cells of pulmonary artery display a background K(+) conductance with biophysical properties resembling those of KCNQ (K(V)7) potassium channels. Therefore, we investigated the expression and functional role of KCNQ channels in pulmonary artery. The effects of selective KCNQ channel modulators were investigated on K(+) current and membrane potential in isolated pulmonary artery smooth muscle cells (PASMCs), on the tension developed by intact pulmonary arteries, and on pulmonary arterial pressure in isolated perfused lungs and in vivo. The KCNQ channel blockers, linopirdine and XE991 [10,10-bis(4-pyridinylmethyl)-9(10H)-anthracenone], inhibited the noninactivating background K(+) conductance in PASMCs and caused depolarization, vasoconstriction, and raised pulmonary arterial pressure without constricting several systemic arteries or raising systemic pressure. The KCNQ channel openers, retigabine and flupirtine, had the opposite effects. PASMCs were found to express KCNQ4 mRNA, at higher levels than mesenteric artery, along with smaller amounts of KCNQ1 and 5. It is concluded that KCNQ channels, most probably KCNQ4, make an important contribution to the regulation of pulmonary vascular tone, with a greater contribution in pulmonary compared with systemic vessels. The pulmonary vasoconstrictor effect of KCNQ blockers is a potentially serious side effect, but the pulmonary vasodilator effect of the openers may be useful in the treatment of pulmonary hypertension.
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Žaloudíková M, Vízek M, Herget J. Hyperoxia blunts acute hypoxia- and PGF2α-induced pulmonary vasoconstriction in chronically hypoxic rats. Physiol Res 2009; 58:917-920. [PMID: 20059290 DOI: 10.33549/physiolres.931878] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
We investigated the influence of oxygenation of in vitro lung
preparation on the pulmonary vascular reactivity. Small
pulmonary vessels isolated from adult male Wistar rats exposed
for 4 days to hypoxia (FiO2 = 0.1, group CH) were compared with
those of normoxic controls (group N). The bath in the chamber of
small vessel myograph was saturated with gas mixture containing
either 21 % or 95 % of O2 with 5 % CO2 and we measured the
reactions of vessels to acute hypoxic challenge with 0 % O2 or to
PGF2α. We did not observe any difference of the contractile
responses between both groups when the normoxic conditions
were set in the bath. When the bath oxygenation was increased
to 95 % O2, the contractions induced by hypoxic challenge and
PGF2α decreased in chronically hypoxic rats and did not change in
normoxic controls. We hypothesize that reduced reactivity of
vessels from hypoxic rats in hyperoxia results from the effect of
chronic hypoxia on Ca2+ signaling in the vascular smooth muscle,
which is modulated by increased free radical production during
the exposure to chronic hypoxia and further hyperoxia.
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Skoumalová A, Herget J, Wilhelm J. Hypercapnia protects erythrocytes against free radical damage induced by hypoxia in exposed rats. Cell Biochem Funct 2008; 26:801-7. [DOI: 10.1002/cbf.1509] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Snorek M, Hodyc D, Neckar J, Tousek F, Wilhelm J, Kolar F, Herget J. Three‐day fasting limits reperfusion ventricular arrhythmias. FASEB J 2008. [DOI: 10.1096/fasebj.22.2_supplement.50] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Jakoubek V, Bíbová J, Herget J, Hampl V. Chronic hypoxia increases fetoplacental vascular resistance and vasoconstrictor reactivity in the rat. Am J Physiol Heart Circ Physiol 2008; 294:H1638-44. [DOI: 10.1152/ajpheart.01120.2007] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
An increase in fetoplacental vascular resistance caused by hypoxia is considered one of the key factors of placental hypoperfusion and fetal undernutrition leading to intrauterine growth restriction (IUGR), one of the serious problems in current neonatology. However, although acute hypoxia has been shown to cause fetoplacental vasoconstriction, the effects of more sustained hypoxic exposure are unknown. This study was designed to test the hypothesis that chronic hypoxia elicits elevations in fetoplacental resistance, that this effect is not completely reversible by acute reoxygenation, and that it is accompanied by increased acute vasoconstrictor reactivity of the fetoplacental vasculature. We measured fetoplacental vascular resistance as well as acute vasoconstrictor reactivity in isolated perfused placentae from rats exposed to hypoxia (10% O2) during the last week of a 3-wk pregnancy. We found that chronic hypoxia shifted the relationship between perfusion pressure and flow rate toward higher pressure values (by ∼20%). This increased vascular resistance was refractory to a high dose of sodium nitroprusside, implying the involvement of other factors than increased vascular tone. Chronic hypoxia also increased vasoconstrictor responses to angiotensin II (by ∼75%) and to acute hypoxic challenges (by >150%). We conclude that chronic prenatal hypoxia causes a sustained elevation of fetoplacental vascular resistance and vasoconstrictor reactivity that are likely to produce placental hypoperfusion and fetal undernutrition in vivo.
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Hodyc D, Snorek M, Brtnicky T, Herget J. Superoxide dismutase mimetic tempol inhibits hypoxic pulmonary vasoconstriction in rats independently on either nitric oxide production or basal tone of pulmonary vessels. FASEB J 2008. [DOI: 10.1096/fasebj.22.1_supplement.1174.4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Chovanec M, Hnilickova O, Smolkova P, Herget J. Interaction of nitric oxide and reactive oxygen species in the development of hypoxic pulmonary hypertension. FASEB J 2008. [DOI: 10.1096/fasebj.22.1_supplement.1209.8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Baňasová A, Maxová H, Hampl V, Vízek M, Povýšilová V, Novotná J, Vajnerová O, Hniličková O, Herget J. Prevention of Mast Cell Degranulation by Disodium Cromoglycate Attenuates the Development of Hypoxic Pulmonary Hypertension in Rats Exposed to Chronic Hypoxia. Respiration 2008; 76:102-7. [DOI: 10.1159/000121410] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2007] [Accepted: 01/09/2008] [Indexed: 01/04/2023] Open
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Maxová H, Novotná J, Vajner L, Tomášová H, Vytásek R, Vízek M, Bačáková L, Valoušková V, Eliášová T, Herget J. In vitro hypoxia increases production of matrix metalloproteinases and tryptase in isolated rat lung mast cells. Physiol Res 2007; 57:903-910. [PMID: 18052689 DOI: 10.33549/physiolres.931278] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Chronic hypoxia results in hypoxic pulmonary hypertension characterized by fibrotization and muscularization of the walls of peripheral pulmonary arteries. This vessel remodeling is accompanied by an increase in the amount of lung mast cells (LMC) and the presence of small collagen cleavage products in the vessel walls. We hypothesize that hypoxia activates LMC, which release matrix metalloproteinases (MMPs) cleaving collagen and starting increased turnover of connective tissue proteins. This study was designed to determine whether in vitro hypoxia stimulates production of MMPs in rat LMC and increases their collagenolytic activity. The LMC were separated on the Percoll gradient and then were divided into two groups and cultivated for 24 h in 21 % O(2) + 5 % CO(2) or in 10 % O(2) + 5 % CO(2). Presence of the rat interstitial tissue collagenase (MMP-13) in LMC was visualized by immunohistological staining and confirmed by Western blot analysis. Total MMPs activity and tryptase activity were measured in both cultivation media and cellular extracts. Exposure to hypoxia in vitro increased the amount of cells positively labeled by anti-MMP-13 antibody as well as activities of all measured enzymes. The results therefore support the concept that LMC are an important source of increased collagenolytic activity in chronic hypoxia.
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Rygl M, Skába R, Herget J, Snajdauf J. [Method of approximative intestinal anastomosis in experimental model]. ROZHLEDY V CHIRURGII : MESICNIK CESKOSLOVENSKE CHIRURGICKE SPOLECNOSTI 2007; 86:501-504. [PMID: 17974144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
AIM A technique of approximative anastomosis in witch integrity and continuity of bowel is achieved with limited number of interrupted seromuscular stitches was evaluated in experimental study. MATERIAL AND METHODS Small bowel anastomosis were performed in twelve rats (Wistar, male) with weight range 197-242 g. An approximative anastomosis in the ileum of six rats was performed with five seromuscular-interrupted sutures only; in the second study group anastomosis was performed with conventional technique of interrupted sutures. The approximative anastomosis was evaluated concerning operating time, anastomotic healing, bursting pressure and adhesions in comparison to the conventional anastomosis. Statistics was calculated with Anova test. RESULTS All anastomosis in both group healed well without obstruction. The median operating time needed for approximative anastomosis was shorter (31.7 +/- 1.6 minutes versus 35.2 +/- 1.5 minutes, p = 0.002). The strength of approximative anastomosis after 7 days was 249 +/- 39 torr; strength of standard anastomosis was 218 +/- 23 torr (p = 0.118). There were no significant differences in the others evaluated parameters between two study groups. CONCLUSION In the animal model presented, the approximative anastomosis shows time saving alternative to standard anastomosis, with the same parameters of anastomotic strength, healing, and adhesions.
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Hodyc D, Snorek M, Brtnický T, Herget J. Superoxide dismutase mimetic tempol inhibits hypoxic pulmonary vasoconstriction in rats independently of nitric oxide production. Exp Physiol 2007; 92:945-51. [PMID: 17496002 DOI: 10.1113/expphysiol.2007.037135] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Hypoxic pulmonary vasoconstriction (HPV), an important physiological mechanism, is regulated by changes in the production of and interactions among reactive oxygen species (ROS). There is controversy, however, over whether HPV is mediated by an increase or a decrease in ROS production. Also, the role of NO in HPV remains unclear. The aim of this study was to investigate whether the inhibition of HPV by the antioxidant tempol was dependent on the concentration of NO, and how its effect was influenced by increased basal pulmonary vascular tone. In isolated rat lungs, we measured vasoconstrictor responses to acute ventilatory hypoxia before and after administration of tempol during perfusion with or without L-NAME. We found that tempol abolished HPV independently of NO production. When we increased basal vascular tone by K(+)-induced depolarization, we also found that tempol completely inhibited HPV. Our results indicate that inhibition of HPV by the superoxide dismutase mimetic tempol does not depend on either NO production or a decrease in basal vascular tone.
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Hodyc D, Johnson E, Hnilicková O, Smolková P, Herget J. Reactive oxygen species production during chronic ventilatory hypoxia. FASEB J 2007. [DOI: 10.1096/fasebj.21.6.a1287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Kolár F, Jezková J, Balková P, Breh J, Neckár J, Novák F, Nováková O, Tomásová H, Srbová M, Ost'ádal B, Wilhelm J, Herget J. Role of oxidative stress in PKC-δ upregulation and cardioprotection induced by chronic intermittent hypoxia. Am J Physiol Heart Circ Physiol 2007; 292:H224-30. [PMID: 16936002 DOI: 10.1152/ajpheart.00689.2006] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The aim was to determine whether increased oxidative stress during the adaptation to chronic intermittent hypoxia (CIH) plays a role in the induction of improved cardiac ischemic tolerance. Adult male Wistar rats were exposed to CIH in a hypobaric chamber (7,000 m, 8 h/day, 5 days/wk, 24–30 exposures). Half of the animals received antioxidant N-acetylcysteine (NAC; 100 mg/kg) daily before the exposure; the remaining rats received saline. Control rats were kept under normoxia and treated in a corresponding manner. One day after the last exposure (and/or NAC injection), anesthetized animals were subject to 20 min of coronary artery occlusion and 3 h of reperfusion for determination of infarct size. In parallel subgroups, biochemical analyses of the left ventricular myocardium were performed. Adaptation to CIH reduced infarct size from 56.7 ± 4.5% of the area at risk in the normoxic controls to 27.7 ± 4.9%. NAC treatment decreased the infarct size in the controls to 42.0 ± 3.4%, but it abolished the protection provided by CIH (to 41.1 ± 4.9%). CIH decreased the reduced-to-oxidized glutathione ratio and increased the relative amount of PKC isoform-δ in the particulate fraction; NAC prevented these effects. The expression of PKC-ε was decreased by CIH and not affected by NAC. Activities of superoxide dismutase, catalase, and glutathione peroxidase were affected by neither CIH nor NAC treatment. It is concluded that oxidative stress associated with CIH plays a role in the development of increased cardiac ischemic tolerance. The infarct size-limiting mechanism of CIH seems to involve the PKC-δ-dependent pathway but apparently not the increased capacity of major antioxidant enzymes.
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Vajner L, Vytásek R, Lachmanová V, Uhlík J, Konrádová V, Novotná J, Hampl V, Herget J. Acute and chronic hypoxia as well as 7-day recovery from chronic hypoxia affects the distribution of pulmonary mast cells and their MMP-13 expression in rats. Int J Exp Pathol 2006; 87:383-91. [PMID: 16965566 PMCID: PMC2517379 DOI: 10.1111/j.1365-2613.2006.00493.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Chronic hypoxia results in pulmonary hypertension due to vasoconstriction and structural remodelling of peripheral lung blood vessels. We hypothesize that vascular remodelling is initiated in the walls of prealveolar pulmonary arteries by collagenolytic metalloproteinases (MMP) released from activated mast cells. Distribution of mast cells and their expression of interstitial collagenase, MMP-13, in lung conduit, small muscular, and prealveolar arteries was determined quantitatively in rats exposed for 4 and 20 days to hypoxia as well as after 7-day recovery from 20-day hypoxia (10% O2). Mast cells were identified using Toluidine Blue staining, and MMP-13 expression was detected using monoclonal antibody. After 4, but not after 20 days of hypoxia, a significant increase in the number of mast cells and their MMP-13 expression was found within walls of prealveolar arteries. In rats exposed for 20 days, MMP-13 positive mast cells accumulated within the walls of conduit arteries and subpleurally. In recovered rats, MMP-13 positive mast cells gathered at the prealveolar arterial level as well as in the walls of small muscular arteries; these mast cells stayed also in the conduit part of the pulmonary vasculature. These data support the hypothesis that perivascular pulmonary mast cells contribute to the vascular remodelling in hypoxic pulmonary hypertension in rats by releasing interstitial collagenase.
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Hodyc D, Hnilickova O, Volek J, Hampl V, Herget J. Tempol Reduces Warm Ischemic Damage of Lung Functions In Non‐Heart‐Beating Donors if Added Pre‐arrestly but Doesn’t Have any Protective Effect on Ischemia – Reperfusion Injury. FASEB J 2006. [DOI: 10.1096/fasebj.20.4.a399-a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Bacakova L, Vytasek R, Maxova H, Novotna J, Eckhart A, Herget J. Tu-P7:265 Collagen I modified by matrix metalloprotease 13 or mast cells decreases adhesion and stimulates growth of vascular smooth muscle cells. ATHEROSCLEROSIS SUPP 2006. [DOI: 10.1016/s1567-5688(06)80968-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Hampl V, Bíbová J, Banasová A, Uhlík J, Miková D, Hnilicková O, Lachmanová V, Herget J. Pulmonary vascular iNOS induction participates in the onset of chronic hypoxic pulmonary hypertension. Am J Physiol Lung Cell Mol Physiol 2005; 290:L11-20. [PMID: 16113050 DOI: 10.1152/ajplung.00023.2005] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Pathogenesis of hypoxic pulmonary hypertension is initiated by oxidative injury to the pulmonary vascular wall. Because nitric oxide (NO) can contribute to oxidative stress and because the inducible isoform of NO synthase (iNOS) is often upregulated in association with tissue injury, we hypothesized that iNOS-derived NO participates in the pulmonary vascular wall injury at the onset of hypoxic pulmonary hypertension. An effective and selective dose of an iNOS inhibitor, L-N6-(1-iminoethyl)lysine (L-NIL), for chronic peroral treatment was first determined (8 mg/l in drinking water) by measuring exhaled NO concentration and systemic arterial pressure after LPS injection under ketamine+xylazine anesthesia. A separate batch of rats was then exposed to hypoxia (10% O2) and given L-NIL or a nonselective inhibitor of all NO synthases, N(G)-nitro-L-arginine methyl ester (L-NAME, 500 mg/l), in drinking water. Both inhibitors, applied just before and during 1-wk hypoxia, equally reduced pulmonary arterial pressure (PAP) measured under ketamine+xylazine anesthesia. If hypoxia continued for 2 more wk after L-NIL treatment was discontinued, PAP was still lower than in untreated hypoxic controls. Immunostaining of lung vessels showed negligible iNOS presence in control rats, striking iNOS expression after 4 days of hypoxia, and return of iNOS immunostaining toward normally low levels after 20 days of hypoxia. Lung NO production, measured as NO concentration in exhaled air, was markedly elevated as early as on the first day of hypoxia. We conclude that transient iNOS induction in the pulmonary vascular wall at the beginning of chronic hypoxia participates in the pathogenesis of pulmonary hypertension.
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