Necrosis In Rats Research Articles

Combined Effects of Vincristine and Quercetin in Reducing Isoproterenol-Induced Cardiac Necrosis in Rats.

Combined effects of vincristine and quercetin in the regulation of isoproterenol (ISO)-induced cardiac necrosis have been evaluated in rats. ISO administration (100mg/kg, s.c., for two consecutive days) increased the levels of serum creatine kinase-MB (CK-MB), lactate dehydrogenase (LDH), glutamate pyruvate transaminase (SGPT) and cardiac troponin (cTnT) as well as cardiac lipid peroxidation products (malondialdehyde and lipid hydroperoxides). However, it reduced the activities of superoxide dismutase (SOD), catalase and the glutathione peroxidase and the level of reduced glutathione. It also increased the heart rate and ST-segment elevation in ECG. Pretreatment of vincristine (25μg/kg) or quercetin (10mg/kg) alone for 2weeks ameliorated these cardiotoxic effects partially. However, treatment of both vincristine and quercetin for a similar period reduced the serum CK-MB, LDH, SGPT and cTnT levels near to normal levels in ISO-treated rats. Concomitantly, the test drugs improved the status of antioxidants and decreased the cardiac lipid peroxidation products. Combined treatment of both the drugs also restored the pathological electrocardiographic patterns and reduced the area of myocardial necrosis. Histopathology of heart in ISO-administered rats that received both vincristine and quercetin showed nearly normal myocardium with very little inflammatory infiltration. In conclusion, the present finding appears to be the first one, suggesting a better protection of cardiac tissues by combined treatment of vincristine and quercetin in isoproterenol-induced cardiac toxicity.

Cardioprotective effect of a chronic treatment of Ginkgo biloba Phytosomes in isoproterenol-induced cardiac necrosis in rats : Involvement of antioxidant system

The present study investigates the cardioprotective effect and antioxidant activity of a chronic treatment of Ginkgo biloba Phytosomes (GBP) in isoproterenol (ISO) induced cardiac necrosis in rats. Pretreatment of GBP 100 mg/kg daily for 30 & 45 days to rats treated with ISO (85 mg/kg, s.c) on the last 2 days, resulted in a significant cardioprotective activity reflected by attenuation of the ISO-elevated levels of serum marker enzymes (aspartate aminotransferase, lactate dehydrogenase & creatine phosphokinase) and malondialdehyde, and restoration of the activities and levels of the ISO-depleted marker enzymes, reduced glutathione and antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase & glutathione reductase) in the heart. However, oral administration of GBP 200 mg/kg to ISO treated rats exhibited lesser cardioprotective effect than GBP 100 mg/kg. It may be concluded that GBP 100 mg/kg oral treatment to ISO challenged rats augments endogenous antioxidants of rat heart, enhances scavenging of free radicals and inhibits lipid peroxidation of membrane, thereby salvaging the myocardium from the deleterious effects of ISO.

Antioxidant and cardioprotective effects of Garcinia indica (kokoberry), an Indian super fruit in isoproterenol induced myocardial necrosis in rats

BACKGROUND: Garcinia indica Choisy, a slender evergreen tree is endemic to the west coast of India. The dried rind of the fruit of Garcinia indica is an Indian spice and a food additive. Many therapeutic effects of the fruit have been reported in literature. OBJECTIVE: The present study investigates the cardioprotective and antioxidant activity of a hydroalcoholic extract of Garcinia indica fruit rind (GIE) in isoproterenol (ISO) induced myocardial necrosis in rats. METHODS: Male Wistar rats were treated with GIE (400 & 800 mg/kg, po) daily for 30 days and administered ISO (85 mg/kg, sc) on the last 2 days at an interval of 24 hr to induce myocardial injury. Activities of marker enzymes (AST, LDH and CK-MB) were assessed in serum and heart. The lipid peroxidation marker malondialdehyde and endogenous antioxidants viz., reduced glutathione, superoxide dismutase, catalase, glutathione peroxidase and glutathione reductase were assayed in heart. RESULTS: Significant myocardial necrosis, depletion of GSH levels, decrease in antioxidant and marker enzyme activities in the heart homogenate, elevation in malondialdehyde levels and an increase in serum levels of marker enzymes (AST, LDH & CK-MB) was observed in ISO treated rats when compared with normal rats. Pre-treatment of GIE to ISO treated rats resulted in a significant attenuation of the ISO-elevated levels of serum marker enzymes and malondialdehyde, and restoration of the levels of the ISO-depleted marker enzymes, reduced glutathione and antioxidant enzymes. The biochemical results were corroborated by electrocardiographic and histopathological findings. CONCLUSION: It may be concluded that GIE oral treatment to ISO challenged rats augments endogenous antioxidants of rat heart, enhances scavenging of free radicals and inhibits lipid peroxidation of membrane, thereby salvaging the myocardium from the deleterious effects of ISO.

18F-fluoromethylcholine (FCho), 18F-fluoroethyltyrosine (FET), and 18F-fluorodeoxyglucose (FDG) for the discrimination between high-grade glioma and radiation necrosis in rats: A PET study

IntroductionDiscrimination between (high-grade) brain tumor recurrence and radiation necrosis (RN) remains a diagnostic challenge because both entities have similar imaging characteristics on conventional magnetic resonance imaging (MRI). Metabolic imaging, such as positron emission tomography (PET) could overcome this diagnostic dilemma. In this study, we investigated the potential of 2-[18F]-fluoro-2-deoxy-D-glucose (18F-FDG), O-(2-[18F]-fluoroethyl)-L-tyrosine (18F-FET), and [18F]-Fluoromethyl-dimethyl-2-hydroxyethylammonium (18F-fluoromethylcholine, 18F-FCho) PET in discriminating high-grade tumor from RN. MethodsWe developed a glioblastoma (GB) rat model by inoculating F98 GB cells into the right frontal region. Induction of RN was achieved by irradiating the right frontal region with 60Gy using three arcs with a beam aperture of 3×3mm (n=3). Dynamic PET imaging with 18F-FDG, 18F-FET, and 18F-FCho, as well as 18F-FDG PET at a delayed time interval (240min postinjection), was acquired. ResultsMRI revealed contrast-enhancing tumors at 15days after inoculation (n=4) and contrast-enhancing RN lesions 5–6months postirradiation (n=3). On 18F-FDG PET, the mean lesion-to-normal ratio (LNRmean) was significantly higher in GB than in RN (p=0.034). The difference in the LNRmean between tumors and RN was higher on the late 18F-FDG PET images than on the PET images reconstructed from the last time frame of the dynamic acquisition (this is at a conventional time interval). LNRs obtained from 18F-FCho PET were not significantly different between GB and RN (p=1.000). On 18F-FET PET, the LNRmean was significantly higher in GB compared to RN (p=0.034). ConclusionsUnlike 18F-FCho, 18F-FDG and 18F-FET PET were effective in discriminating GB from RN. Interestingly, in the case of 18F-FDG, delayed PET seems particularly useful. Advances in knowledge and implications for patient careOur results suggest that (delayed) 18F-FDG and 18F-FET PET can be used to discriminate GB (recurrence) from RN. Confirmation of these results in clinical studies is needed.

Protective effects of Parinari curatellifolia flavonoids against acetaminophen-induced hepatic necrosis in rats

In the present study, we investigated the hepatoprotective potential of Parinari curatellifolia Planch (Chrysobalanaceae) in experimental rats in order to ascertain the validity of folkloric claims of its effectiveness in the treatment of hepatic-related disorders. Flavonoid extract of P. curatellifolia seed, PCF (10-, 20- or 30mg/kg body weight) or silymarin (25mg/kg), dissolved in corn oil, was administered by gavage to experimental animals once daily for 14 consecutive days before liver damage was chemically induced through the administration of acetaminophen (2g/kg p.o.) on the 14th day. Hepatoprotection was assessed by analyzing liver homogenate and serum for markers of hepatotoxicity – alanine aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamyl transferase (GGT) and lactate dehydrogenase (LDH) activities as well as prothrombin time (PT). Evaluation of biochemical indices of oxidative stress – level of lipid peroxides (LPO), activities of superoxide dismutase (SOD) and catalase, along with histological assessment of hepatic tissue sections were also carried out. Results revealed that all doses of PCF significantly (P<0.001) and dose dependently prevented acetaminophen-induced increase in serum activities of hepatic enzymes (ALT, AST, GGT, LDH) and PT. Furthermore, PCF (10- and 20mg/kg) significantly (P<0.001) reduced lipid peroxidation in liver tissue and restored the activities of the antioxidant enzymes SOD and catalase toward normal levels. Histopathology of the liver tissue showed that PCF mitigated the toxicant-induced hepatocellular necrosis, reduced inflammatory cell infiltration and enhanced hepatocyte regeneration. The results indicated that P. curatellifolia flavonoids demonstrated remarkable hepatoprotective activity in acute liver injury caused by acetaminophen.

Evaluation of Renal Protection From High Doses of Melatonin in an Experimental Model of Renal Ischemia and Reperfusion in Hyperglycemic Rats

BackgroundMelatonin is a free radical scavenger with important actions in the study of renal ischemia and reperfusion (I/R). This study evaluated possible renal protection of high doses of melatonin in an experimental model of I/R in which rats were submitted to acute hyperglycemia under anesthesia with isoflurane. MethodForty-four male Wistar rats, weighing more than 300 g, were randomly divided into 5 groups: G1, sham (n = 10); G2, melatonin (n = 10; 50 mg.kg−1); G3, hyperglycemia (n = 9; glucose 2.5 g.kg−1); G4, hyperglycemia/melatonin (n = 10; 2.5 g.kg−1 glucose + melatonin 50 mg.kg−1); and G5, I/R (n = 5). In all groups, anesthesia was induced with 4% isoflurane and maintained with 1.5% to 2.0% isoflurane. Intraperitoneal injection of melatonin (G1, G4), glucose (G3, G4), or saline (G1, G5) was performed 40 minutes before left renal ischemia. Serum plasma values for creatinine and glucose were determined at baseline (M1), immediately following reperfusion (M2), and 24 hours after completion of the experiment (M3). Histological analysis was performed to evaluate tubular necrosis (0–5). ResultsSerum glucose was higher at M2 in the groups supplemented with glucose, hyperglycemia (356.00 ± 107.83), and hyperglycemia/melatonin (445.3 ± 148.32). Creatinine values were higher at T3 (P = .0001) for I/R (3.6 ± 0.37), hyperglycemia/melatonin (3.9 ± 0.46), and hyperglycemia (3.71 ± 0.69) and lower in the sham (0.79 ± 0.16) and melatonin (2.01 ± 1.01) groups, P < .05. Histology showed no necrosis injury in the G1, lesion grade 2 in the G2, and severe acute tubular necrosis in the G3: (grade 4), G4: (grade 5) and G5: (grade 4) groups (P < .0001). DiscussionMelatonin protected the kidneys submitted to I/R in rats without hyperglycemia; however, this did not occur when the I/R lesion was associated with hyperglycemia. ConclusionsDue to its antioxidant and antiapoptotic action, melatonin was able to mitigate, but not prevent acute tubular necrosis in rats with hyperglycemia under anesthesia by isoflurane.

PDE-5 inhibition improves skin flap viability in rats that are exposed to nicotine

Nicotine causes ischemia and necrosis of skin flaps. Phosphodiesterase-5 (PDE-5) inhibition enhances blood flow and vasculogenesis. This study examines skin flap survival in rats exposed to nicotine that are treated with and without PDE-5 inhibition. Eighty six rats were divided into five groups. Group 1 received saline subcutaneous (SC) once per day. Group 2 received nicotine SC 2 mg/kg day. Group 3 received sildenafil intraperitoneal (IP) 10 mg/kg day. Group 4 received nicotine SC 2 mg/kg and sildenafil IP 10 mg/kg day. Group 5 received nicotine SC 2 mg/kg day and sildenafil IP 10 mg/kg two times daily. After 28 days of treatment, modified McFarlane flaps were created, silicone sheets were interposed, and flaps were sutured. Photographs were taken on postoperative days 1, 3, and 7 and fluorescence angiography was used on day 7, both to evaluate for skin flap necrosis. Rats were euthanized and flaps were harvested for Vascular Endothelial Growth Factor (VEGF) Western blot analysis. Images were analyzed by three blinded observers using ImageJ, and necrotic indices were calculated. The nicotine and PDE-5 inhibition twice-daily group showed a 46% reduction in flap necrosis when compared to saline only (P < 0.05) and a 54% reduction when compared to nicotine only (P < 0.01). Fluorescence angiographic image analysis revealed reductions in flap necrosis (P < 0.01). VEGF analysis trended toward increased VEGF for all sildenafil-treated groups (P > 0.05). PDE-5 inhibition exhibits a dose-dependent reduction in skin flap necrosis in rats exposed to nicotine. This suggests that PDE-5 inhibition may mitigate the ill effects of smoking on skin flaps.

Inflammatory response and neuronal necrosis in rats with cerebral ischemia.

In the middle cerebral artery occlusion model of ischemic injury, inflammation primarily occurs in the infarct and peripheral zones. In the ischemic zone, neurons undergo necrosis and apoptosis, and a large number of reactive microglia are present. In the present study, we investigated the pathological changes in a rat model of middle cerebral artery occlusion. Neuronal necrosis appeared 12 hours after middle cerebral artery occlusion, and the peak of neuronal apoptosis appeared 4 to 6 days after middle cerebral artery occlusion. Inflammatory cytokines and microglia play a role in damage and repair after middle cerebral artery occlusion. Serum intercellular cell adhesion molecule-1 levels were positively correlated with the permeability of the blood-brain barrier. These findings indicate that intercellular cell adhesion molecule-1 may be involved in blood-brain barrier injury, microglial activation, and neuronal apoptosis. Inhibiting blood-brain barrier leakage may alleviate neuronal injury following ischemia.

Protective effect of ethanolic extract of Tabernaemontana divaricata (L.) R. Br. against DEN and Fe NTA induced liver necrosis in Wistar Albino rats.

This study is an attempt to evaluate the hepatoprotective activity of Tabernaemontana divaricata against DEN and Fe NTA induced liver necrosis in rats. Ethanolic extract of the whole plant of Tabernaemontana divaricata at doses of 200 and 400 mg/kg body weight and 5-fluorouracil (standard drug) was orally administered to male Wistar Albino rats once daily for 24 weeks, simultaneously treated with the carcinogen DEN and Fe NTA. In simultaneously treated animals, the plant extract significantly decreased the levels of uric acid, bilirubin, AST, ALT, and ALP in serum and increased the levels of liver marker enzymes in liver. Treatment with the extracts resulted in a significant increase in the levels of antioxidants accompanied by a marked reduction in the levels of malondialdehyde when compared to DEN and Fe NTA treated group. When compared with 200 mg/kg bw rats, 400 mg/kg bw rats and 5-fluorouracil treated rats showed better results in all the parameters. The histopathological studies confirmed the protective effects of extract against DEN and Fe NTA induced liver necrosis. Thus, it could be concluded that the use of Tabernaemontana divaricata extract in the treatment of carcinogen induced hepatic necrosis.

Sulfated polysaccharide isolated from Ulva lactuca attenuates d-galactosamine induced DNA fragmentation and necrosis during liver damage in rats

Context: Ulva lactuca Linnaeus (Chlorophyceae), a commonly distributed seaweed, is rich in polysaccharide but has not been studied extensively.Objective: The present study investigated the effects of crude fraction of Ulva lactuca polysaccharide (ULP) on d-galactosamine (d-Gal)-induced DNA damage, hepatic oxidative stress, and necrosis in rats.Materials and methods: The rats were treated with ULP (100 mg/kg, orally) for 4 weeks before a single intraperitoneal injection of d-Gal (500 mg/kg). In addition to liver cell necrosis and DNA damage, antioxidant parameters, such as lipid peroxide (LPO), superoxide dismutase, and catalase, and histopathology of liver tissue were evaluated.Results: ULP pre-treatment significantly attenuated a d-Gal-induced decrease in DNA and RNA levels (3.67 ± 0.38) and (5.42 ± 0.46), respectively. Comet tail length and acridine staining confirmed the number of cells undergoing necrosis were relatively lower in ULP treated rats (30 µm and 8–10% of counted cells) compared to rats treated with d-Gal (60 µm and 16% of counted cells). Biochemical (LPO, SOD and CAT) and histological evaluation (p < 0.01) confirmed the anti-hepatotoxic and antioxidant property of crude polysaccharide against d-Gal-induced elevation of LPO and infiltration of inflammatory cells into liver tissue.Discussion and conclusion: Although our previous studies have reported on the protective role of ULP against liver toxicity, our present findings show that ULP improved the hepatic antioxidant defense system against d-Gal-induced DNA damage and necrosis in rats.

Effect of iodothyronine hormone status on doxorubicin related cardiotoxicity

The anthracycline anticancer agent doxorubicin has been recognised to induce a dose-dependent cardiotoxicity. The chronic form of such complication is characterized by an irreversible cardiac damage and congestive heart failure. Although the pathogenesis of anthracycline cardiotoxicity seems to be multifactorial, the pivotal role has been attributed to reactive oxygen species formation. Because redox equilibrium in cardiomyocytes may be regulated via iodothyronine hormones, the aim of the study was to appraise the effect of hypothyroidism on heart damages induced by doxorubicin. The rats received methimazole in drinking water (0.001 and 0.025%) after doxorubicin administration (2.0, 5.0 and 15 mg/kg). The cardiac morphology and blood biochemical markers of heart damage were assessed. Decreased levels of iodothyronine hormones had not significant impact on cardiac morphological changes and no effect on the level of B-type natriuretic peptide in rats receiving doxorubicin. Lower hormonal levels had sporadic, diverse effect on blood transaminases, lactate dehydrogenase and creatine kinase levels, but any relation to time, doxorubicin doses and hypothyroid status was found. Hypothyreosis leads to increase in fatty acid binding protein in rats receiving higher dose of doxorubicin. Hypothyreosis had no effect on heart stretching and on necrosis at morphological level, but caused biochemical symptoms of cardiomyocyte necrosis in rats receiving doxorubicin.

Cardioprotective effect of vincristine on isoproterenol-induced myocardial necrosis in rats

This study investigated the protective effect of vincristine (VCR) on isoproterenol (ISO)-induced cardiac necrosis (CN) in rats. Animals (n=7 in each group) were pretreated with vincristine (25µg/kg) intraperitoneal (i.p.) daily in 5-day cycles with 2 days pause between cycles using a 5-day-on, 2-day-off schedule for two weeks and then intoxicated with isoproterenol (100mg/kg, s.c., for 2 consecutive days). ISO-induced myocardial damage was indicated by changes in electrocardiographic (ECG) patterns, increased activities of marker enzymes such as creatine kinase-MB, serum glutamate pyruvate transaminase and lactate dehydrogenase and the levels of troponin-T in the serum. The levels of lipid peroxide products, (thiobarbituric acid reactive substances (TBARS) and lipid hydroperoxides (HP)) were increased with a parallel decrease in the activities of antioxidants (superoxide dismutase, catalase, glutathione peroxidase and reduced glutathione) in ISO-induced rats. Furthermore, ISO-induced rats showed increase in the activities of membrane bound enzymes such as Ca2+-ATPase and Mg2+-ATPase with a decreased activity of Na+/K+-ATPase. Triphenyl tetrazolium chloride (TTC) staining of the heart section showed increased area of necrosis in ISO-induced rats. Pretreatment with VCR (25µg/kg) eliminated all ISO-induced biochemical and histopathological changes, and decreased the myocardial necrosis to a greater extent. Transmission electron microscopic findings on the structure of the heart mitochondria confirmed the protective effects of VCR. Present study provides first scientific report on protective effect of vincristine against ISO-induced cardiac damage in rats.

Effect of dichloromethylene diphosphonate on liver regeneration following thioacetamide-induced necrosis in rats

To study the effect of dichloromethylene diphosphonate (DMDP), a selective Kupffer cell toxicant in reference to liver damage and postnecrotic liver regeneration in rats induced by sublethal dose thioacetamide (TA). Rats, intravenously (iv) pre-treated with a single dose of DMDP (10 mg/kg), were intraperitoneally (ip) injected with TA 6.6 mmol/kg (per 500 mg/kg body weight). Hepatocytes were isolated from rats at 0, 24, 48 and 72 h following TA intoxication and blood and liver samples were obtained. To evaluate the mechanisms involved in the postnecrotic regenerative state, DNA distribution and ploidy time course were assayed in isolated hepatocytes. Circulating cytokine tumor necrosis factor-alpha (TNF-α) was assayed in serum and determined by reverse transcriptase-polymerase chain reaction in liver extract. The effect of DMDP induced noticeable changes in postnecrotic regeneration, causing an increased percentage of hepatocytes in the cell cycle S phase. The increase at 24 h in S1 population in rats pretreated with DMDP + TA was significantly (P < 0.05) different compared with that of the TA group (18.07% vs 8.57%). Hepatocytes increased their proliferation as a result of these changes. Also, TNF-α expression and serum level were increased in rats pre-treated with DMDP. Thus, DMDP pre-treatment reduced TA-induced liver injury and accelerated postnecrotic liver regeneration. These results demonstrate that Kupffer cells are involved in TA-induced liver, as well as in postnecrotic proliferative liver states.

Renoprotective effects of the crude extract and solvent fractions of the leaves of Euclea divinorum Hierns against gentamicin-induced nephrotoxicity in rats

Ethnopharmacological relevanceEuclea divinorum Hierns (Ebenaceae) is used in Ethiopian folklore medicine to treat scabies, inflammation of the skin, eczema, abdominal pain, gonorrhea, and kidney problems. However, the claim has not been scientifically validated. Aim of the studyTo assess the renoprotective effects of the crude extract and solvent fractions of E. divinorum leaves against gentamicin-induced nephrotoxicity in rats. Materials and methodRats of either sex were divided into seven experimental groups, each comprising six animals. Group I served as control and given vehicle (Tween 80, 2%, v/v in water) and Group II were treated with gentamicin intraperitoneally (100mg/kg/day) for eight days. Group III–V received crude extract at three different doses 100mg/kg, 150mg/kg and 200mg/kg, respectively. Group VI received 100mg/kg of the methanolic fraction and Group VII 100mg/kg of the aqueous fraction. The extract was administered orally two days before and eight days concomitantly with gentamicin. Following treatment, blood and renal tissue were used to assess creatinine, blood urea nitrogen (BUN), malondialdehyde (MDA), antioxidant enzymes and tubular necrosis using recommended procedures. In addition, free radical scavenging activity was determined using in vitro methods. ResultsGentamicin significantly increased serum creatinine and BUN, MDA and tubular necrosis in rats. It also decreased activity of catalase and superoxide dismutase as well as levels of gluthatione. Pre- and co-treatment with the crude extract and solvent fractions of Euclea divinorum leaves reversed gentamicin-induced alterations as evidenced by a decrease in tubular necrosis, serum and oxidant markers as well as by an increase in antioxidant molecules. Effect was found to decrease with dose when the crude extract was used and maximum protection was conferred by 100mg/kg of the methanolic fraction in both in vivo and in vitro studies. ConclusionsEuclea divinorum reversed gentamicin-induced nephrotoxicity, probably via its antioxidant activity. The fact that the methanol fraction conferred maximum protection suggests that semi-polar antioxidant principles might be responsible for the observed effect.

Cardio protective effect of Coriandrum sativum L. on isoproterenol induced myocardial necrosis in rats

The preventive effect of Coriandrum sativum L. (CS) on cardiac damage was evaluated by Isoproterenol (IP) induced cardiotoxicity model in male Wistar rats. Rats were pretreated with methanolic extract of CS seeds at a dose of 100, 200 or 300mg/kg orally for 30days and they were subsequently administered (s.c.) with IP (85mg/kg body weight) for the last two days. IP treated rats showed increased LPO, decreased levels of endogenous antioxidants and ATPases in the cardiac tissue together with increased plasma lipids and markers of cardiac damage. TTC staining showed increased infarct areas while HXE staining showed myofibrillar hypertrophy and disruption. CS (200 and 300mg/kg body weight) pretreatment significantly prevented or resisted all these changes. Our results show that methanolic extract of CS is able to prevent myocardial infarction by inhibiting myofibrillar damage. It is also concluded that, the rich polyphenolic content of CS extract is responsible for preventing oxidative damage by effectively scavenging the IP generated ROS.

Effects of hypercholesterolemia on contrast media-induced nephrotoxicity in rats

To explore the effects of short- and long-term dietary hypercholesterolemia on contrast media-induced nephrotoxicity in rats. The male Wistar rats were fed either a normal rodent diet or a high cholesterol diet. At the end of 2 and 8 weeks, 8 rats from each group received a tail vein injection of either Iohexol injection (groups NC and HC) or vehicle (groups N and H). Blood lipid, renal function, renal hemodynamics, renal and urinary prostaglandin E2 (PGE2) and thromboxane B2 (TXB2), renal nitric oxide and malondialdehyde (MDA) were determined at Day 1 following the administration of contrast media. The dosing of contrast media induced obviously increased serum creatinine compared with normal rats ((185 ± 28) vs (53 ± 3) µmol/L, P < 0.01) and severe renal tubular necrosis in rats with a high cholesterol diet for 8 weeks but did not in normal-diet rats or rats with a high cholesterol diet for 2 weeks. The renal and urinary levels of PGE2 and TXB2 increased significantly in rats of groups H and HC at the end of 8 weeks. The renal production of nitric oxide decreased while the concentration of MDA increased markedly in groups HC and H at the end of 8 weeks. Long-term hypercholesterolemia appears to be a risk factor of contrast media-induced acute renal failure. And it may be associated with the disorder of intrarenal prostaglandins and the abnormality of renal nitric oxide system as induced by lipid peroxidation.

Nephroprotective effects of subcapsular transplantation of metanephric mesenchymal cells on gentamicin-induced acute tubular necrosis in rats

The subcapsular transplantation of metanephric mesenchymal cells (MMCs) may be a new therapeutic approach for the treatment of acute tubular necrosis (ATN). To investigate this hypothesis and provide evidence for its possible use in the clinic, we evaluated the nephroprotective effects of transplanting MMCs into the renal subcaspsule of rats with ATN induced by gentamicin. MMCs were expanded in culture. After gentamicin-induced ATN was established, fluorescently-labeled cells were transplanted and traced in kidney tissues by fluorescence microscopy. Serum creatinine (Cr), urea nitrogen (BUN), and N-acetyl-b-D-glucosaminidase (NAG) levels were determined at different time points. Kidney pathology was studied by hematoxylin-eosin staining. Apoptosis was examined by the TUNEL assay. In the MMCs-treated group, the mortality rate decreased; BUN, Cr, and NAG levels peaked at 8 days, and were significantly lower than those in the other groups at 11 and 14 days. RIMM-18 cells locally recruited through precise tropism to sites of injury had the ability to migrate into the tubuli from the renal subcapsule. Damage to the cell-treated kidneys was reduced. The pathologic lesion scores of tubular damage reached the highest values at 8 days in the treated kidneys and 11 days in the untreated ones. The apoptotic index showed that the peaks of apoptosis occurred at earlier stages of the injury process in cell-treated than in untreated kidney and thereafter declined in a time-dependent manner. The subcapsular transplantation of MMCs could ameliorate renal function and repair kidney injury.

Renal infarction due to oral contraceptive pills.

A previously healthy, 35-year-old woman, mother of two children, presented with a 3-day history of abdominal discomfort, vomiting and anuria for 2 days. She had no history of diabetes or hypertension. She had been using a combination of ethinylestradiol and drospirenone as a contraceptive for the previous 3 years. Her investigations at presentation were: serum creatinine: 7.9 mg/dL (698 μmol/L), blood urea nitrogen: 185 mg/dL (66 mmol/L), serum proteins: 8.2 g/dL, serum albumin: 4.5 g/dL, serum homocysteine: 4.2 μmol/L (0.56 mg/L), haemoglobin: 11.2 g/dL, total leucocyte count: 4800/mm3, platelet count: 340 × 109/L, prothrombin time: 15.0 sec (control: 13.0 sec), activated partial thromboplastin time: 28.0 sec (control: 30.0 sec), thrombin time: 10.0 sec (control: 8.0 sec), bleeding time: 4.0 min (reference range: 2.0–7.0 min), clotting time: 5.0 min (reference range: 5.0–7.0 min), serum fibrinogen: 444 mg/dL (range: 150–400 mg/dL) and D-dimer: 1.7 μg/mL (range: 0.5 μg/mL). Kidney sizes on ultrasound were right: 12.4 × 4.6 cm and left: 11.5 × 4.4 cm. Doppler of the renal arteries revealed severe decrease and pruning of the segmental, inter-lobar and arcuate vessels and absence of the cortical blush in both of the kidneys. Urine dipstick examination for proteins was negative. A renal biopsy was done after a session of haemodialysis. It revealed coagulative necrosis (infarct) of the cortex of the kidney, and the artery included in the biopsy was obstructed by fibrin thrombus (Figure 1). She was not pregnant and had no congenital heart disease. There was no history of acute gastroenteritis, trauma or snakebite. There was no history or clinical features suggestive of haemolytic uraemic syndrome. There were no schistocytes on peripheral smear. Electrocardiogram showed normal sinus rhythm with no ischaemic or chamber enlargement changes. Echocardiography revealed normal cardiac chambers and normal valves. The reports of anti-thrombin III: 0.25 g/L (range: 0.19–0.31 g/L), protein C: 90% (range: 70–160%) and protein S: 80% (range: 60–150%). Prothrombin time and partial thromboplastin times were not prolonged in order to investigate for factor V Leiden mutation. Flow cytometry did not find a reduction in CD 55 and CD 59 on red blood cells, thus excluding paroxysmal nocturnal haemoglobinuria. Anti-phospholipid antibodies, lupus antibody, anti-nuclear antibodies and anti-double-stranded DNA were negative. Fig. 1. Renal biopsy showing cortical necrosis and the artery occluded by fresh fibrin thrombus (arrow) in an artery (SMPASX40). The patient did not regain renal function. She was initiated on continuous ambulatory peritoneal dialysis. One of the adverse effects of oral contraceptive pills is arterial thrombosis. There are experimental reports of acute cortical necrosis in rats induced by oestrone and vasopressin administration [1]. There are a few reports of acute cortical necrosis in patients who used oral contraceptives, but these patients had other features like factor V Leiden mutation [2] and smoking [3].

Synthesis of 2’-(5-Chloro-2-Hydroxybenzylidene) Benzenesulfanohydrazide Schiff Base and its Anti- Ulcer Activity in Ethanol-Induced Gastric Mucosal Lesions in Rats

Purpose: To study the anti-ulcer activity of 2’-(5-Chloro-2-hydroxybenzylidene) benzenesulfanohydrazide Schiff base against ethanol-induced gastric mucosal lesions in rats. Methods: 2’-(5-Chloro-2-hydroxybenzylidene) benzenesulfano-hydrazide (Cl-BzSO-HAP) was synthesized, and structurally characterized by elemental analysis, FT-IR, 1 H-NMR and C-NMR. Its preventive activity against ulcer induced by absolute ethanol in Sprague-Dawley rats were studied in vivo. Twenty four Sprague Dawley (SD) rats (12 males and 12 females) were assigned equally into 4 groups (n = 6), including negative control and positive control groups. The third group received a low oral dose of the compound (50 mg/kg) while the fourth group was administered a high oral dose (100 mg/kg). The degree of gastric lesion formation was assessed. Prior to dosing, the animals were fasted overnight. Results: Cl-BzSO-HAP showed significant preventive activity against ulcer induced by absolute ethanol. Oral administration of the compound (both low and high doses) prior to ethanol administration inhibited gastric lesion formation by 88.0 and 94.9 %, respectively, compared to 82.7 % for the positive control, cimetidine. Conclusion: Extensive gastric necrosis in rats induced by absolute ethanol was prevented by administration of Cl-BzSO-HAP resulting in reduced or total absence of lesions. Keywords: Benzenesulfanohydrazone, Schiff base, Gastric ulcer, Histology.

Development of a novel animal model to differentiate radiation necrosis from tumor recurrence

Distinguishing tumor progression from radiation necrosis after treatment in patients with brain tumors presents a clinical dilemma. A well-characterized, orthotopic rodent model of radiation-induced brain necrosis including a tumor is not currently available The objective of the study was to create focal radiation necrosis in rat brain bearing human glioblastoma (GBM) using stereotactic radiosurgery and confirm it by immuno-histological analysis. Nude rats implanted with primary GBM cells were irradiated using a stereotactic setup (n = 3) or received no radiation (n = 3). Ten weeks after the implantation, growth of the tumor was confirmed by magnetic resonance imaging (MRI). For each animal, MRI and contrast-enhanced CT images were obtained and fused using registration software. The tumor was identified and delineated using the fused CT/MR images. A treatment plan was generated using a 4 mm radiosurgery cone such that one portion of the tumor receives 100% dose of 60 Gy sufficient to cause necrosis, whereas the tumor edge at depth receives only 50% or less dose, allowing for regrowth of the tumor. The brains were collected 10 weeks after irradiation and immuno-histological analysis was performed. Hematoxylin and eosin staining showed central liquefaction necrosis in the high dose region consistent with necrosis and viable tumor in the peripheral low dose region. Ki-67 staining showed highly proliferative tumor cells surrounding the necrotic parts of the tumor. Luxol fast blue and lectin staining showed demyelination and vascular injury in brain tissue consistent with radiation necrosis. We have developed a novel model of radiation necrosis in rats bearing glioma.