Hypothermic treatment reduces matrix metalloproteinase-9 expression and damage in the liver following asphyxial cardiac arrest in rats / 한국실험동물학회지

Background@#Hypothermic treatment is known to protect organs against cardiac arrest (CA) and improves survival rate. However, few studies have evaluated the effects of hypothermia on CA-induced liver damages. This study was designed to analyzed the possible protective effects of hypothermia on the liver after asphyxial CA (ACA). Rats were randomly subjected to 5 min of ACA followed by return of spontaneous circulation (ROSC). Body temperature was controlled at 37 ± 0.5 °C (normothermia group) or 33 ± 0.5 °C (hypothermia group) for 4 h after ROSC. Liver tissues were extracted and examined at 6 h, 12 h, 1 day, and 2 days after ROSC. @*Results@#The expression of infiltrated neutrophil marker CD11b and matrix metallopeptidase-9 (MMP9) was investigated via immunohistochemistry. Morphological damage was assessed via hematoxylin and eosin (H & E) staining. Hypothermic treatment improved the survival rate at 6 h, 12 h, 1 day, and 2 days after ACA. Based on immunohistochemical analysis, the expression of CD11b and MMP9 was significantly increased from 6 h after ACA in the normothermia group. However, the expressions of CD11b and MMP9 was significantly decreased in the hypothermia group compared with that of the normothermia group. In addition, in the results of H & E, sinusoidal dilatation and vacuolization were apparent after ACA; however, these ACA-induced structural changes were reduced by the 4 h-long hypothermia. @*Conclusions@#In conclusion, hypothermic treatment for 4 h inhibited the increases in CD11b and MMP9 expression and reduced the morphological damages in the liver following ACA in rats. This study suggests that hypothermic treatment after ACA reduces liver damages by regulating the expression of CD11b and MMP9.

Hypothermic treatment reduces matrix metalloproteinase-9 expression and damage in the liver following asphyxial cardiac arrest in rats / 한국실험동물학회지

Background@#Hypothermic treatment is known to protect organs against cardiac arrest (CA) and improves survival rate. However, few studies have evaluated the effects of hypothermia on CA-induced liver damages. This study was designed to analyzed the possible protective effects of hypothermia on the liver after asphyxial CA (ACA). Rats were randomly subjected to 5 min of ACA followed by return of spontaneous circulation (ROSC). Body temperature was controlled at 37 ± 0.5 °C (normothermia group) or 33 ± 0.5 °C (hypothermia group) for 4 h after ROSC. Liver tissues were extracted and examined at 6 h, 12 h, 1 day, and 2 days after ROSC. @*Results@#The expression of infiltrated neutrophil marker CD11b and matrix metallopeptidase-9 (MMP9) was investigated via immunohistochemistry. Morphological damage was assessed via hematoxylin and eosin (H & E) staining. Hypothermic treatment improved the survival rate at 6 h, 12 h, 1 day, and 2 days after ACA. Based on immunohistochemical analysis, the expression of CD11b and MMP9 was significantly increased from 6 h after ACA in the normothermia group. However, the expressions of CD11b and MMP9 was significantly decreased in the hypothermia group compared with that of the normothermia group. In addition, in the results of H & E, sinusoidal dilatation and vacuolization were apparent after ACA; however, these ACA-induced structural changes were reduced by the 4 h-long hypothermia. @*Conclusions@#In conclusion, hypothermic treatment for 4 h inhibited the increases in CD11b and MMP9 expression and reduced the morphological damages in the liver following ACA in rats. This study suggests that hypothermic treatment after ACA reduces liver damages by regulating the expression of CD11b and MMP9.

The relationship between low survival and acute increase of tumor necrosis factor α expression in the lung in a rat model of asphyxial cardiac arrest / 대한해부학회지

Cardiac arrest (CA) is sudden loss of heart function and abrupt stop in effective blood flow to the body. The patients who initially achieve return of spontaneous circulation (RoSC) after CA have low survival rate. It has been known that multiorgan dysfunctions after RoSC are associated with high morbidity and mortality. Most previous studies have focused on the heart and brain in RoSC after CA. Therefore, the aim of this research was to perform serological, physiological, and histopathology study in the lung and to determine whether or how pulmonary dysfunction is associated with low survival rate after CA. Experimental animals were divided into sham-operated group (n=14 at each point in time), which was not subjected to CA operation, and CA-operated group (n=14 at each point in time), which was subjected to CA. The rats in each group were sacrificed at 6 hours, 12 hours, 24 hours, and 2 days, respectively, after RoSC. Then, pathological changes of the lungs were analyzed by hematoxylin and eosin staining, Western blot and immunohistochemistry for tumor necrosis factor α (TNF-α). The survival rate after CA was decreased with time past. We found that histopathological score and TNF-α immunoreactivity were significantly increased in the lung after CA. These results indicate that inflammation triggered by ischemia-reperfusion damage after CA leads to pulmonary injury/dysfunctions and contributes to low survival rate. In addition, the finding of increase in TNF-α via inflammation in the lung after CA would be able to utilize therapeutic or diagnostic measures in the future.

Changes in histopathology and tumor necrosis factor-α levels in the hearts of rats following asphyxial cardiac arrest

OBJECTIVE: Post cardiac arrest (CA) syndrome is associated with a low survival rate in patients who initially have return of spontaneous circulation (ROSC) after CA. The aim of this study was to examine the histopathology and inflammatory response in the heart during the post CA syndrome. METHODS: We induced asphyxial CA in male Sprague-Dawley rats and determined the survival rate of these rats during the post resuscitation phase. RESULTS: Survival of the rats decreased after CA: 66.7% at 6 hours, 36.7% at 1 day, and 6.7% at 2 days after ROSC following CA. The rats were sacrificed at 6 hours, 12 hours, 1 day, and 2 days after ROSC, and their heart tissues were examined. Histopathological scores increased at 12 hours post CA and afterwards, histopathological changes were not significant. In addition, levels of tumor necrosis factor-α immunoreactivity gradually increased after CA. CONCLUSION: The survival rate of rats 2 days post CA was very low, even though histopathological and inflammatory changes in the heart were not pronounced in the early stage following CA.

Changes in Histopathology and Tumor Necrosis Factor-αLevels in the Hearts of Rats Following Asphyxial Cardiac Arrest

PURPOSE: Post cardiac arrest (CA) syndrome is associated with a low survival rate in patients who initially have a return of spontaneous circulation (ROSC) after the CA. The aim of this study was to examine the histopathology and inflammatory response in the heart during post CA syndrome. METHODS: Asphyxial CA was induced in male Sprague-Dawley rats and the survival rate of the rats was determined during the post resuscitation phase. RESULTS: Survival of the rats decreased after CA: 66.7% at 6 hours, 36.7% at 1 day, and 6.7% at 2 days after the ROSC following CA. The rats were sacrificed at 6 hours, 12 hours, 1 day, and 2 days after the ROSC, and their heart tissues were examined. Histopathological scores increased at 12 hours post CA. Afterwards, the histopathological changes were not significant. In addition, the levels of tumor necrosis factor-αimmunoreactivity increased gradually after CA. CONCLUSION: The survival rate of the rats 2 days post CA was very low, even though the histopathological and inflammatory changes in the heart were not pronounced in the early stages following the CA.

Cardiac Physiologic Regulation of Sub-type Specific Adrenergic Receptors in Transgenic Mice Overexpressing β1- and β2-Adrenergic Receptors

PURPOSE: A combination of β1-adrenergic receptor (β₁-AR) blockade and β₂-AR activation might potentially be the novel therapy for treating heart failure. However, the use of β-AR agonists and/or antagonists in the clinical setting is controversial due to the lack of information on cardiac inotropic or chronotropic regulation by AR signaling. METHODS: In this study, we performed a hemodynamic evaluation by examining the force frequency response (FFR), Frank-Starling relationship, and response to non-selective β-AR agonist (isoproterenol) in the hearts isolated from 6-month-old transgenic (TG) mice overexpressing β₁- and β₂-ARs (β₁- and β₂-AR TG mice, respectively). RESULTS: Cardiac physiologic consequences of β₁- and β₂-AR overexpression resulted in a similar maximal response to that of isoproterenol and faster temporary decline of positive inotropic response in β₂-AR TG mice. β₁-AR TG mice showed a pronounced negative limb of FFR, whereas β2-AR TG mice showed high stimulation frequencies with low contractile depression during FFR. Contrastingly, Frank-Starling relationship was equally enhanced in both β₁- and β₂-AR TG mice. CONCLUSION: Hemodynamic evaluation performed in the present study showed a difference between β₁- and β₂-AR signaling, which may be due to a difference in the desensitization of β₁- and β₂-ARs.

Cardiac physiologic regulation of sub-type specific adrenergic receptors in transgenic mice overexpressing β₁- and β₂-adrenergic receptors

OBJECTIVE: Combination of β₁-adrenergic receptor (AR) blockade and β₂-AR activation might be a potential novel therapy for treating heart failure. However, use of β-AR agonists and/or antagonists in the clinical setting is controversial because of the lack of information on cardiac inotropic or chronotropic regulation by AR signaling. METHODS: In this study, we performed hemodynamic evaluation by examining force frequency response (FFR), Frank-Starling relationship, and response to a non-selective β-AR agonist (isoproterenol) in hearts isolated from 6-month-old transgenic (TG) mice overexpressing β₁- and β₂-ARs (β₁- and β₂-AR TG mice, respectively). RESULTS: Cardiac physiologic consequences of β₁- and β₂-AR overexpression resulted in similar maximal response to isoproterenol and faster temporary decline of positive inotropic response in β₂-AR TG mice. β₁-AR TG mice showed a pronounced negative limb of FFR, whereas β₂-AR TG mice showed high stimulation frequencies with low contractile depression during FFR. In contrast, Frank-Starling relationship was equally enhanced in both β₁- and β₂-AR TG mice. CONCLUSION: Hemodynamic evaluation performed in the present showed a difference in β₁- and β₂-AR signaling, which may be due to the difference in the desensitization of β₁- and β₂-ARs.

Oenanthe Javanica Extract Protects Against Experimentally Induced Ischemic Neuronal Damage via its Antioxidant Effects / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Water dropwort (Oenanthe javanica) as a popular traditional medicine in Asia shows various biological properties including antioxidant activity. In this study, we firstly examined the neuroprotective effect of Oenanthe javanica extract (OJE) in the hippocampal cornus ammonis 1 region (CA1 region) of the gerbil subjected to transient cerebral ischemia.</p><p><b>METHODS</b>Gerbils were established by the occlusion of common carotid arteries for 5 min. The neuroprotective effect of OJE was estimated by cresyl violet staining. In addition, 4 antioxidants (copper, zinc superoxide dismutase [SOD], manganese SOD, catalase, and glutathione peroxidase) immunoreactivities were investigated by immunohistochemistry.</p><p><b>RESULTS</b>Pyramidal neurons in the CA1 region showed neuronal death at 5 days postischemia; at this point in time, all antioxidants immunoreactivities disappeared in CA1 pyramidal neurons and showed in many nonpyramidal cells. Treatment with 200 mg/kg, not 100 mg/kg, OJE protected CA1 pyramidal neurons from ischemic damage. In addition, 200 mg/kg OJE treatment increased or maintained antioxidants immunoreactivities. Especially, among the antioxidants, glutathione peroxidase immunoreactivity was effectively increased in the CA1 pyramidal neurons of the OJE-treated sham-operated and ischemia-operated groups.</p><p><b>CONCLUSION</b>Our present results indicate that treatment with OJE can protect neurons from transient ischemic damage and that the neuroprotective effect may be closely associated with increased or maintained intracellular antioxidant enzymes by OJE.</p>

Effect of Oenanthe Javanica Extract on Antioxidant Enzyme in the Rat Liver / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Oenanthe javanica (O. javanica) has been known to have high antioxidant properties via scavenging reactive oxygen species. We examined the effect of O. javanica extract (OJE) on antioxidant enzymes in the rat liver.</p><p><b>METHODS</b>We examined the effect of the OJE on copper, zinc-superoxide dismutase (SOD1), manganese superoxide dismutase (SOD2), catalase (CAT), and glutathione peroxidase (GPx) in the rat liver using immunohistochemistry and western blot analysis. Sprague-Dawley rats were randomly assigned to three groups; (1) normal diet fed group (normal-group), (2) diet containing ascorbic acid (AA)-fed group (AA-group) as a positive control, (3) diet containing OJE-fed group (OJE-group).</p><p><b>RESULTS</b>In this study, no histopathological finding in the rat liver was found in all the experimental groups. Numbers of SOD1, SOD2, CAT, and GPx immunoreactive cells and their protein levels were significantly increased in the AA-fed group compared with those in the normal-group. On the other hand, in the OJE-group, numbers of SOD1, SOD2, CAT, and GPx immunoreactive cells in the liver were significantly increased by about 190%, 478%, 685%, and 346%, respectively, compared with those in the AA-group. In addition, protein levels of SOD1, SOD2, CAT, and GPx in the OJE-group were also significantly much higher than those in the AA-group.</p><p><b>CONCLUSION</b>OJE significantly increased expressions of SOD1 and SOD2, CAT, and GPx in the liver cells of the rat, and these suggests that significant enhancements of endogenous enzymatic antioxidants by OJE might be a legitimate strategy for decreasing oxidative stresses in the liver.</p>

Oenanthe javanica extract increases immunoreactivities of antioxidant enzymes in the rat kidney / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Oenanthe javanica is an aquatic perennial herb originated from East Asia. Nowadays, the effects of Oenanthe javanica have been proven in various disease models. Studies regarding the antioxidant effect of Oenanthe javanica in the kidney are still unclear.</p><p><b>METHODS</b>This study was therefore performed to investigate the effect of the Oenanthe javanica extract (OJE) in the rat kidney using immunohistochemistry for antioxidant enzymes, copper, zinc-superoxide dismutase (SOD1), manganese superoxide dismutase (SOD2), catalase (CAT) and glutathione peroxidase (GPx). Sprague-Dawley rats were randomly assigned to three groups: (1) normal diet fed-group (normal-group), (2) diet containing ascorbic acid (AA)-fed group (AA-group) as a positive control, (3) diet containing OJE-fed group (OJE-group). AA and OJE were supplied during 28 days.</p><p><b>RESULTS</b>The side-effects were not observed in all the groups. Immunoreactivities of SOD1, SOD2, CAT and GPx were easily detected in the distal tubules of the kidney, and their immunoreactivities in the AA-and OJE-groups were increased to about 1.4-1.5 times and 2 times, respectively, compared with those in the normal-group.</p><p><b>CONCLUSION</b>OJE significantly increased expressions of SOD1 & 2, CAT and GPx immunoreactivities in the distal tubules of the rat kidney, and this finding suggests that significant enhancements of endogenous enzymatic antioxidants by OJE treatment may be a legitimate strategy for decreasing oxidative stresses in the kidney.</p>

Changes in the Testis Interstitium of Rabbits from Birth to Sexual Maturity / 체질인류학회지

Changes in the testis interstitium from birth to adulthood were studied in New Zealand white rabbits of 1, 7, 21, 35, 49, 70, 105, 147, 196, and 252 days (n=8 per group) of age. Testes of rabbits were fixed by whole body perfusion using a fixative containing 2.5% glutaraldehyde in cacodylate buffer, processed and embedded in Epon-araldite. Using 1 microm sections stained with methylene blueazure II, qualitative and quantitative (stereological) morphological studies were performed. Sperm production was measured by routine technique. The volume density of the interstitium represents 66.3% of the testicular parenchyma at day 1. Adult Leydig cells initially detected at day 7 (0.001%), increased progressively to reach a volume density of 2.6% by day 252. The absolute volume of mesenchymal cells, endothelial cells, pericytes, and myoid cells increased from birth to 252 days. The number of endothelial cells, pericytes, and myoid cells per testis increased gradually with age. The absolute numbers of adult Leydig cells and mesenchymal cells per testis increased linearly from birth to 252 days. The rate of production of adult Leydig cells was greater than that of mesenchymal cells in the postnatal rabbit testis through 252 days. The average volume of a mesenchymal cell increased from day 1 to day 70 and declined thereafter; the highest value was at day 70. Total sperm production and daily sperm production per testis increased significantly from 105 to 252 days of age. These results clarified the pattern of changes in the testis interstitium in rabbits from birth to adulthood and correlation these events with spermatogenesis.

Changes in the Testis Interstitium of Rabbits from Birth to Sexual Maturity / 체질인류학회지

Changes in the testis interstitium from birth to adulthood were studied in New Zealand white rabbits of 1, 7, 21, 35, 49, 70, 105, 147, 196, and 252 days (n=8 per group) of age. Testes of rabbits were fixed by whole body perfusion using a fixative containing 2.5% glutaraldehyde in cacodylate buffer, processed and embedded in Epon-araldite. Using 1 microm sections stained with methylene blueazure II, qualitative and quantitative (stereological) morphological studies were performed. Sperm production was measured by routine technique. The volume density of the interstitium represents 66.3% of the testicular parenchyma at day 1. Adult Leydig cells initially detected at day 7 (0.001%), increased progressively to reach a volume density of 2.6% by day 252. The absolute volume of mesenchymal cells, endothelial cells, pericytes, and myoid cells increased from birth to 252 days. The number of endothelial cells, pericytes, and myoid cells per testis increased gradually with age. The absolute numbers of adult Leydig cells and mesenchymal cells per testis increased linearly from birth to 252 days. The rate of production of adult Leydig cells was greater than that of mesenchymal cells in the postnatal rabbit testis through 252 days. The average volume of a mesenchymal cell increased from day 1 to day 70 and declined thereafter; the highest value was at day 70. Total sperm production and daily sperm production per testis increased significantly from 105 to 252 days of age. These results clarified the pattern of changes in the testis interstitium in rabbits from birth to adulthood and correlation these events with spermatogenesis.

Regulation of IGF System in Rats after Experimental Myocardial Infarction / 체질인류학회지

Insulin-like growth factor system (IGF system) has been reported to be associated with the variety of disorders of myocardial function. However, the effect of myocardial infarction (MI) on the IGF system has not been fully described. Thus, the present study was to investigate in more detail the changes of IGF system in the male rat following myocardial infarction (MI). Ligation of the left coronary artery was performed in male Sprague-Dawley male rats at 60 days of age. Control rats were obtained sham-operated animals. MI rats were sacrificed at 1, 3, 7, 14, and 30 day after ligation of left anterior descending coronary artery. Control rats were sacrificed on 30 day after thoracotomy. Myocardial infarct size was assessed by planimetry and perimetry. Serum and heart concentrations of IGF-I and -II were determined by radioimmunoassay. Serum levels of IGF-binding protein (IGFBP)-1 and IGFBP-3 were analyzed with a two-site immunoradiometric assay. Mean infarct size was 35.2~42.3% of the left ventricle after coronary occlusion in experimental groups. Serum levels of IGF-I were markedly reduced, but the levels of IGF-II were not altered in MI rats compared with shamligated controls. Serum IGFBP-I levels in MI rats were significantly increased at 1 and 3 day compared with sham rats. The levels of serum IGFBP-3 were significantly higher in the ligated rats. IGF-I levels of the infarct/periinfarct area of the left ventricle were significantly decreased in rats with myocardial infarction, whereas the levels of IGF-II remained unchanged. These results demonstrate that the IGF system is altered in the myocardial infarction and suggest that the IGF system plays an important role in the response of the heart to myocardial infarction.

Morphometric Studies in the Leydig Cell of Hemicastrated Rats / 체질인류학회지

The present study was conducted to investigate the influence of hemicastration and age at hemicastraion on the subsequent Leydig cell morphology and function of male rats. Sprague Dawley rats were left intact or hemicastrated at 20, 30, 40, 50, or 60 days of age (n=18 rats per group). At 100 days of age, all rats were sacrificed. Testes were fixed by whole body perfusion using a fixative containing 2.5% glutaraldehyde in cacodylate buffer, processed and embedded in Epon-araldite. Using 1 micrometer sections stained with methylene blue, qualitative and quantitative morphological studies were performed. Testis incubations were used to determine lutenizing hormone (LH; 100 ng/mL) stimulated testosterone secretory capacity per testis in vitro. Testosterone levels in the incubation medium, and testosterone and LH levels in serum of these six groups of rats were determined by radioimmunoassay. Body and testis weights were not changed by hemicastration between experimental and control groups. Volume density of seminiferous tubules, interstitium, and Leydig cells was not significantly affected by hemicastration. Absolute volume of seminiferous and interstitium was significantly increased in unilaterally castrated rats at 20, 30 and 40 days of age compared to control. Significant increases in the total number of Leydig cells per testis occurred in rats hemicastrated at 20, 30, 40 and 50 days of age compared to control. A significant increase in average volume of a Leydig cell was noted in the hemicastrated rats at 30 and 40 days compared to intact rats of the same age but was significantly decreased at 60 days of age. Serum testosterone levels and LH-stimulated testosterone production per testis were significantly (P<0.05) increased in the hemicastrated rats at 30 and 40 days. In summary, when rats were unilaterally castrated at 20, 30, 40, 50, and 60 days of age, those rats hemicastrated at 30 and 40 days showed compensatory hypertrophy/hypersecretion of Leydig cells when killed at 100 days of age. Especially, these data suggested that compensatory hypertrophy/hypersecretion of Leydig cells in rats hemicastrated around the time of puberty occurs in the remaining testis.

The Effect of Myocardial Infarction on the Reproductive Function in Adult Male Rats / 체질인류학회지

The present study was to investigate in more detail the changes of reproductive function in the male rat following myocardial infarction (MI). Ligation of the left coronary artery was performed in male Sprague-Dawley male rats at 60 days of age. Control rats were obtained sham-operated animals. MI rats were sacrificed at 1, 3, 5, 7, 14, and 30 day after ligation of left anterior descending coronary artery. Control rats were sacrificed on 30 day after thoracotomy. Myocardial infarct size was assessed by planimetry and perimetry. Testes of rats were fixed by whole body perfusion using a fixative containing 2.5% glutaraldehyde in cacodylate buffer, processed and embedded in Epon-araldite. Using 1 micro sections stained with methylene blue-azure II, qualitative and quantitative (stereological) morphological studies were performed. Testosterone levels in the incubation medium of luteinizing hormone-stimulated (100 ng/mL) testosterone secretion per testis in vitro, and in serum were determined by radioimmunoassay. Sperm production was measured by routine technique. Mean infarct size was 29.5~33.5% of the left ventricle after coronary occlusion in experimental groups. No changes were observed in testis volume, absolute volume of Leydig cell, Leydig cell size, and number of Leydig cell per testis in MI rats compared to sham-operated animals. Serum testosterone, LH-stimulated testicular testosterone production, and daily sperm production in MI rats were not significantly different (P>0.05) from sham-operated animals. These results demonstrate that under the experimental conditions employed here, experimental chronic myocardial infarction does not exert adverse effects on the reproductive function of male rats.