Lungs Of Wistar Rats Research Articles

Ex-vivo biological tissue differentiation by the Distribution of Relaxation Times method applied to Electrical Impedance Spectroscopy

We present the distribution of relaxation times (DRT) method applied to the electrical impedance spectrum data for improving the differentiation of biological tissues by means of two scenarios, a non-parametric representation and a parametric model. The complex electrical impedance from 1 kHz to 1 MHz was measured for ex-vivo WISTAR rat liver, heart, kidney, lung, muscle, and spleen tissues using a homemade electrical impedance spectroscopy (EIS) instrument and analyzed by the DRT method in a time constant domain revealing a particular non-parametric representation for differentiating each tissue using the retrieved distribution function. A larger number of relaxation time constants are found giving the possibility of studying the different polarization processes related to the tissues. We propose a parametric impedance model associated to DRT in the frequency domain to estimate the complex impedance of EIS measurements. Our results were compared with that obtained by the classical impedance Cole-Cole model.

Effects of furosemide administration on the concentration of essential and toxic elements in Wistar rats by inductively coupled plasma optical emission spectrometry

Furosemide can interfere with the metabolism of chemical elements, changing their levels in several tissues, thus causing imbalance. In this study, inductively coupled plasma optical emission spectrometry (ICP OES) was used for multi-element analysis (Cd, Cu, Fe, Mg, Pb, Se and Zn) after microwave-assisted digestion, to evaluate the effect of furosemide (loop diuretic) on the composition of these essential and toxic elements in biological samples (liver, kidney, heart, lung and serum) of Wistar rats. Male and female Wistar rats (n = 40, 180–350 g) were randomly divided into 2 groups (n = 20/group). The results were expressed as μg/g dry weight. The mean tissue concentrations (minimum-maximum in μg/g) of Cu, Fe, Mg and Zn in the biological samples ranged between 5.2 and 1023.5. The levels of Cd, Pb and Se were below the detection limit of the ICP OES. Accuracy was assessed by microwave-assisted digestion and recovery values of 83–116% were obtained. Liver had significantly higher trace element concentrations in most of the analyzed samples. Mg showed a significant reduction (for males and females) in its levels in the heart. In both genders, there was similarity in the Cu concentration reduction (around 16%) for all tissues. The highest iron losses were found for serum (52% and 12%) for male and female rats, respectively. Reductions in Zn occurred between 0.3 and 18.0%, mainly for kidneys and heart, respectively. This study demonstrated that furosemide altered the concentration of some elements in rats.

Lung injury and expression of p53 and p16 in Wistar rats induced by respirable chrysotile fiber dust from four primary areas of China.

Chrysotile products were widely used in daily life, and a large amount of respirable dust was produced in the process of production and application. At present, there was seldom research on the safety of chrysotile fiber dust, and whether its long-term inhalation can lead to lung cancer was unknown. In order to determine whether respirable chrysotile fiber dust of China caused lung cancer, four major chrysotile-producing mine areas in China were selected for this study. Chrysotile fibers were prepared into respirable dust. Particle size was measured by laser particle analysis, morphology was observed by scanning electron microscope, chrysotile fiber phase was analyzed by X-ray diffraction, trace chemical elements were identified by X-ray fluorescence, and the structure and the active groups of the dust were determined after grinding by Fourier transform infrared spectroscopy. Male Wistar rats were exposed to non-exposed intratracheal instillation with different concentrations of chrysotile fiber dust. The rats were weighed after 1, 3, and 6months, then the lung tissues were separated, the lung morphology was observed, and the pulmonary index was calculated. Pathological changes in lung tissues were observed by optical microscope after the HE staining of tissues, and the gene expression of p53 and p16 was determined by reverse transcription polymerase chain reaction. First, the results showed that the particle sizes of the four fibers were less than 10μm. Four primary areas of chrysotile had similar fibrous structure, arranged in fascicles, or mixed with thin chunks of material. Second, the elementary composition of the four fibers was mainly chrysotile, and the structure and the active groups of the grinding dust were not damaged. Third, the weights of the treated rats were obviously lower, and the lung weights and the pulmonary index increased significantly (P<0.05). Fourth, the treated Wistar rat lung tissues revealed different degrees of congestion, edema, inflammatory cell infiltration, and mild fibrosis. Fifth, the p53 and p16 genes decreased in the Mangnai group after 1month of exposure, and the other groups increased. The expression of p53 and p16 in each group decreased significantly after 6months (P<0.05). In conclusion, the respirable chrysotile fiber dust from the four primary areas of China had the risk of causing lung injury, and these changes may be related to the physical and chemical characteristics of chrysotile from different production areas.

Effects of emissions from sugar cane burning on the trachea and lungs of Wistar rats.

ABSTRACTObjective:To evaluate the effects of exposure to emissions from sugar cane burning on inflammatory mechanisms in tissues of the trachea and lung parenchyma in Wistar rats after different periods of exposure. Methods:This was an experimental open randomized study. The animals were divided into four groups: a control group (CG) underwent standard laboratory conditions, and three experimental groups were exposed to emissions from sugar cane burning over different periods of time, in days-1 (EG1), 7 (EG7), and 21 (EG21). After euthanasia with 200 mg/kg of ketamine/xylazine, fragments of trachea and lung were collected and fixed in 10% formalin. Histological analyses were performed with H&E and picrosirius red staining. Results:No inflammatory infiltrates were found in the tissues of CG rats. The histological examination of tissues of the trachea and lung parenchyma revealed that the inflammatory process was significantly more intense in EG7 than in the CG (p < 0.05 and p < 0.01, respectively). In comparison with the CG and EG1, angiogenesis in the lung parenchyma and collagen deposition in tracheal tissues were significantly greater only in EG21 (p < 0.001 and p < 0.01, respectively). Conclusions:In this sample, emissions from sugar cane burning induced acute focal and diffuse inflammation in the lamina propria of tracheal tissues, with no loss of ciliated epithelial tissue. In the lung parenchyma of the animals in the experimental groups, there was interstitial and alveolar edema, together with polymorphonuclear cell infiltrates.

Evaluation of sepsis treatment with enteral glutamine in rats.

to analyze the influence of glutamine on morphological and histological changes observed in the ileum, lung, kidney and liver of Wistar rats subjected to sepsis. we induced sepsis by cecal ligature and puncture. We divided the animals in two groups: group A, control, with five animals, and group B, experience, with ten animals that received enteral glutamine two days before sepsis induction. We used histological analysis to rank the injury according to a score dependent on the injury severity and the affected organ. The sum of values assigned to each animal resulted in a final grade. We assessed the villi in the ileum, microgoticular steatosis in the liver, interstitial pneumonitis in the lungs, and vacuolation of the proximal convoluted tubules in the kidneys. cell lysis and destruction of the villi of the ileum were more intense in the control group when compared with animals receiving glutamine. In the kidney, we found more pronounced vacuolization in the proximal convoluted tubules in the control group compared with animals receiving glutamine. Both microgoticular steatosis and interstitial pneumonitis were similar between groups. administration of enteral glutamine prior to sepsis preserved the histological structure.

Stimulatory effect of desipramine on lung metastases of adenocarcinoma MADB 106 in stress highly-sensitive and stress non-reactive rats

The effect of antidepressant drugs on tumor progress is very poorly recognized. The aim of the present study was to examine the effect of individual reactivity to stress and 24-day desipramine (DES) administration on the metastatic colonization of adenocarcinoma MADB 106 cells in the lungs of Wistar rats. Wistar rats were subjected to stress procedure according to the chronic mild stress (CMS) model of depression for two weeks and stress highly-sensitive (SHS) and stress non-reactive (SNR) rats were selected. SHS rats were more prone to cancer metastasis than SNR ones and chronic DES treatment further increased the number of lung metastases by 59% and 50% in comparison to vehicle-treated appropriate control rats. The increase in lung metastases was connected with DES-induced skew macrophage activity towards M2 functional phenotype in SHS and SNR rats. Moreover, during 24h after DES injection in healthy rats, the decreased number of TCD8+ and B cells in SHS and SNR rats as well as NK cell cytotoxic activity in SNR rats could be attributed to the lowered capacity to defend against cancer metastasis observed in chronic DES treated and tumor injected rats.

Changes in miRNA in the lung and whole blood after whole thorax irradiation in rats

We used a rat model of whole thorax x-ray irradiation to profile the microRNA (miRNA) in lung and blood up to 4 weeks after radiation. MiRNA from normal and irradiated Wistar rat lungs and whole blood were analyzed by next-generation sequencing and the changes by radiation were identified by differential deRNA-seq 1, 2, 3 and 4 weeks after irradiation. The average total reads/library was 2,703,137 with a mean of 88% mapping to the rat genome. Detailed profiles of 100 of the most abundant miRNA in rat blood and lung are described. We identified upregulation of 4 miRNA, miR-144-5p, miR-144-3p, miR-142-5p and miR-19a-3p in rat blood 2 weeks after radiation that have not previously been shown to be altered after radiation to the lung. Ingenuity Pathway Analysis identified signaling of inflammatory response pathways. These findings will support development of early detection methods, as well as mechanism(s) of injury and mitigation in patients after radiotherapy or radiological accidents.

Effects of ambient PM2.5 and 9-nitroanthracene on DNA damage and repair, oxidative stress and metabolic enzymes in the lungs of rats.

Ambient fine particulate matter (PM2.5) is a complex mixture associated with lung cancer risk. PM2.5-bound nitro-polycyclic aromatic hydrocarbons (NPAHs) have been demonstrated to possess mutagenicity and carcinogenicity. Previous studies showed that PM2.5 induced DNA damage, whereas there is little knowledge of whether 9-nitroanthracene (9-NA), a typical compound of NPAHs in PM2.5, causes DNA damage. Also, the regulating mechanisms of PM2.5 and 9-NA in DNA damage and repair are not yet fully established. Here we sought to investigate the molecular mechanisms of DNA damage and repair in the lungs of male Wistar rats exposed to PM2.5 (1.5 mg per kg body weight) or three different dosages of 9-NA. And then DNA strand breaks, 8-OH-dG formation, DNA-protein crosslink and DNA repair gene expressions in rat lungs were analyzed. In addition, alteration in oxidative stress factors and metabolic enzymes were detected. The results showed that (1) PM2.5 and higher dosage 9-NA (4.0 × 10-5 and 1.2 × 10-4 mg per kg body weight) significantly caused lung DNA damage, accompanied by increasing OGG1 expression while inhibiting MTH1 and XRCC1 expression, elevating the levels of GADD153, hemeoxygenase-1 and malondialdehyde, and promoting the activities of CYP450 isozymes and glutathione S-transferase. (2) 1.3 × 10-5 mg kg-1 9-NA exposure couldn't cause DNA damage and oxidative stress. (3) At the approximately equivalent dose level, PM2.5-induced DNA damage effects were more obvious than 9-NA with positive correlation. It suggests that DNA damage caused by PM2.5 and 9-NA may be mediated partially through influencing the DNA repair capacity and enhancing oxidative stress and biotransformation, and this negative effect of 9-NA might be related to the PM2.5-induced lung genotoxicity.

Evaluation of the dose metric for acute lung inflammogenicity of fast-dissolving metal oxide nanoparticles

Although surface area metric was suggested as an appropriate dose metric for acute lung inflammation of NPs, it might not be effective for fast-dissolving NPs because they lose their reactive surface when dissolved in the phagolysosomes. Herein, we evaluated the dose metric for fast-dissolving NPs using a rat intratracheal instillation model. A panel of fast-dissolving NPs (CoO, CuO and ZnO) and their constituent metal ions (CoCl2, CuCl2 and ZnCl2) were compiled and each compound was intratracheally instilled into the lungs of female Wistar rats at the same molar concentrations in the NP doses (40, 100 and 400 μg/rat). The toxicity endpoints including cytological and biochemical data in bronchoalveolar lavage fluid were evaluated at 24 h after instillation. To evaluate the dose metric, each toxicity endpoint was plotted against the instilled dose (mass or surface area) or the equivalent dose (mass or surface area) that was weighted by the ratio of specific dose-generated responses between metal chlorides. Dose-response curves of fast-dissolving NPs about percentage of granulocytes, lactate dehydrogenase levels and total protein levels showed similar pattern but slightly less potential than those of their respective metal chlorides. When each toxicity endpoint was plotted against the equivalent mass dose, three types of NPs showed more overlapping dose-response curves than other dose metrics. In conclusion, this study implies that the equivalent mass dose is an appropriate dose metric for fast-dissolving NPs and the main factor determining the slope of the dose-response curve is the intrinsic toxicity of the their constituent ions.

The pulmonary phagocytosis response to separate and combined impacts of manganese (IV) and chromium (VI) containing particulates.

We investigated by the optical microscopy some cytological characteristics of the bronchoalveolar lavage fluid cell population 24h after intratracheal instillation of microscale MnO2 and BaCrO4 particles (separately or together at two different doses) into the lungs of Wistar rats. Besides, the cytotoxicity of both particulates for rat peritoneal macrophages in vitro was assessed by the trypan blue exclusion test and proved significant. They were found to evoke a typical dose-dependent pulmonary phagocytosis response usually observed under inhalation or intratracheal impacts of low-soluble mineral and metal particles. A significant shift in the above mentioned cell population toward the prevalence of neutrophllic leukocytes (NL) over alveolar macrophages (AM) proved once more to be the most characteristic feature of this response. Although the particle load of a unit AM was always higher than that of a unit NL, the collective contribution of the recruited NLs to the total particles internalization by both AMs and NLs together was quite significant. This fact confirms that NL recruitment is an important auxiliary mechanism of the cytotoxic particle elimination from lungs compensating for the macrophage damage caused by them. Well adjusted functioning of this compensatory mechanism was additionally demonstrated by isobolographic analysis based on the Response Surface Methodology. On the other hand, this analysis confirmed that the type of combined toxicity depends on a particular effect this type is assessed for and on the effect's dose-dependent level.

Regulatory parameters of the lung immune response during the early phase of experimental trichinellosis

Parasitic infection caused by Trichinella spiralis provokes an early stimulation of the mucosal immune system which causes an allergic inflammatory response in the lungs. The present work was intended to characterize the kinetics of emergence of regulatory parameters in Wistar rat lungs during this early inflammatory response, between days 0 and 13p.i. The presence of regulatory cells such as regulatory T cells (Tregs) and alternatively activated macrophages (AAM) was analyzed in lung cell suspensions. Moreover, a regulatory cytokine (TGF-β) was studied in lung tissue extracts. Considering that newborn larvae (NBL) travel along the pulmonary microvasculature, the ability of this parasite stage to modulate the activation of lung macrophages was evaluated. For this purpose, lung macrophages from non-infected or infected rats (day 6p.i.) were cultured with live or dead NBL. Arginase activity (characteristic of AAM) and nitric oxide (NO produced by iNOS, characteristic of classical activated macrophages) were measured after 48h. Our results revealed a significant increase in the percentage of Tregs on days 6 and 13p.i., arginase activity on day 13p.i. and TGF-β levels on days 6 and 13p.i. Lung macrophages from non-infected rats cultured with live NBL showed a significant increase in arginase activity and NO levels. Live and dead NBL induced a significant increase in arginase activity in lung macrophages from infected rats. Only live NBL significantly increased NO levels in these macrophages. The present work demonstrates for the first time, the emergence of regulatory parameters in the early lung immune response during T. spiralis infection. The immumodulatory properties exerted by NBL during its passage through this organ could be the cause of such regulation. Moreover, we have shown the ability of NBL to activate macrophages from the lung parenchyma by the classical and alternative pathways.

Induction of Lipocalin2 in a Rat Model of Lung Irradiation.

Previously, we showed that lipocalin2 (LCN2) serum levels increased after liver irradiation and during acute-phase conditions. Here, we evaluate LCN2 expression and serum levels after single-dose lung irradiation with 25 Gy, percutaneously administered to the lung of randomly-paired male Wistar rats. Due to the concave anatomy of the lung recesses, the irradiation field included the upper part of the liver. No rat died due to irradiation. In control tissue, lung immunohistochemistry showed a high constitutive expression of LCN2+ granulocytes. LCN2 mRNA levels in lung tissue increased up to 24 h (9 ± 2.3-fold) after irradiation. However, serum LCN2 levels remained undetectable after lung irradiation. LCN2 expression in the upper part of the liver increased up to 4.2-fold after lung irradiation, but the lower liver showed an early decrease. Acute-phase cytokines (IL-1β and TNF-α) showed a significant increase on transcript level in both lung and upper liver, whilst the lower liver did not show any considerable increase. In conclusion, constitutive expression of LCN2 in local immune cells demonstrates its local role during stress conditions in the lung. The absence of LCN2 in the serum strengthens our previous findings that the liver is the key player in secreting LCN2 during stress conditions with liver involvement.

Role of vitamin C against bifenthrin induced oxidative damage in lungs of Wistar rats

The aim of present study was to unravel the protective role of vitamin C on oxidative stress parameters in lung homogenates of bifenthrin intoxicated rats. Rats were divided into four groups. Group I served as control while group II animals were treated with bifenthrin @ 5.8mg/Kg/day. In group III, vitamin C was orally administered @ 60mg/Kg/day where as group IV received both vitamin C and bifenthrin @ 60mg/Kg/day and 5.8mg/Kg/day respectively. After 30th day of treatment, lung samples were taken and analysed for oxidative stress parameters. Significant (P&lt;0.05) increase in lipid peroxidation was observed from control value of 4.80±0.39 to 7.90±0.50 in bifenthrin treated animals. Mean control values of SOD, GSH-Px and CAT were 0.55±0.05, 0.98±0.03 and 138.70±6.01 which were significantly (P&lt;0.05) decreased to values of 0.27±0.0, 0.53±0.05 and 91.10±9.70 respectively in bifenthrin treated animals. The value of GST increased significantly (p&lt;0.05) to 1.05±0.06 in bifenthrin administered animals from control value of 0.70±0.08. Pre-treatment with vitamin C in ameliorative group IV significantly restored the normal values of lipid peroxidation, SOD, GST and CAT but could not reverse the decreased values of GSH-Px. The present research is first of its type where in free radical generation due to bifenthrin –a commonly used insecticide was evaluated in lung homogenates when given orally which might be due to residues present in the lung. Besides it will be helpful in better understanding of toxicological profile of pyrethoids, the most commonly used insecticides.

Protective Role of Grape Seeds Extract against Cadmium Toxicity in the Lung of Male Wistar Rats

Objective: This study was done on 40 male wistar rats to evaluate the curative and protective effect of grape seeds extract on oxidative damage, inflammatory and apoptotic insult on lung tissue induced by cadmium chloride toxicity. Materials and Methods: The rats were classified to control group (group I), cadmium chloride group (group II), grape seeds extract group (group III) and mixture of grape seeds extract and cadmium chloride group (group IV). At the end of the experimental period, the lungs were collected and fixed in formalin saline (10%) for histopathological and immunohistochemical studies. Serum samples and frozen lungs were used for biochemical analyses. Results: The rats groups treated with grape seed showed a significant attenuated oxidative stress by reducing lung tissue malondialdehyde and improving glutathione peroxidase content as well as antioxidant enzymes activities in lung tissues and serum total antioxidant capacity in comparison to group II. The lung tissue of the group II is characterized by thick interalveolar septum, congested and edematous blood vessels. Diffuse and circumscribed lymphocytic infiltration especially around the bronchioles with hyperplasia in the lining cells. Most of the lung tissue showed normal structure as that of the control group except some blood vessels showed congestion in group IV. The immunohistochemical results were negative immunostaining for bcl-2, positive for bax and ki67 in the cadmium treated group, while showed positive immunostaining for bcl-2 in group IV. Conclusion: The addition of grape seeds extract improves the hazard toxic effect of cadmium chloride in the lung tissue through its powerful free radical scavenging property, strong antioxidant activity and effective anti-apoptotic potential.

MicroRNA expression profiles and target prediction in neonatal Wistar rat lungs during the development of bronchopulmonary dysplasia.

In this study, we investigated the mechanisms through which microRNAs (miRNAs or miRs) regulate lung development after birth, as well as the role of miRNAs in the development of bronchopulmonary dysplasia (BPD). For this purpose, a total of 90 neonatal Wistar rats were randomly and equally assigned to either a model group or a control group. On postnatal days 3, 7 and 14, the lung tissues were collected for histological analysis to determine morphological changes. The expression levels of proliferating cell nuclear antigen (PCNA) and platelet endothelial cell adhesion molecule-1 (PECAM-1, also known as CD31) were measured by RT-qPCR and western blot analysis. A miRCURY™ LNA array was employed to screen for differentially expressed miRNAs, and the possible target genes of those miRNAs were predicted. Our results revealed that, compared with the control group, the following changes induced by hyperoxia were observed in the model group over time: a decrease in the number, but an increase in the size of the alveoli, and a decrease in the number of secondary septa formed. In the model group, from postnatal days 3–14, the mRNA and protein expression levels of PCNA and CD31 were significantly lower than those in the control group. The differentially expressed miRNAs between the 2 groups were identified on days 3, 7 and 14 after birth. Possible target genes were identified for 32 differentially expressed miRNAs. Taken together, these findings suggest that during the development of BPD, an alveolarization disorder with microvascular dysplasia co-exists with the differential expression of certain miRNAs during the different stages of alveolar development in a neonatal rat model of hyperoxia-induced BPD. This indicates that miRNAs may participate in the occurrence and development of BPD.

Effect of Crude Ethanolic Leaf Extract of Rauwolfia Vomitoria on the Fetal Lungs of Wistar Rats

Article History Rauwolfia vomitoria is a plant used in the treatment of hypertension, schizophrenia, and insomnia among others. This study investigated the effects of Rauwolfia vomitoria on the histology of the fetal lungs. Fifteen female Wistar rats weighing 180-200 g were divided into three groups (A, B, and C), consisting of five rats each. The animals mated overnight at estrous and the morning after coitus was designated day zero of pregnancy. Oral doses of 150 mg/kg and 250 mg/kg of ethanolic leaf extract of Rauwolfia vomitoria were administered to pregnant rats in groups B and C, respectively on day 7-11 of gestation, while group A served as the control group and were given distilled water. On day 20 of gestation, the rats were sacrificed and their fetuses examined and weighed. Fetal body weight, crown-rump and tail lengths were measured. Result showed significant (P < 0.05) higher anthropometric parameters, and the histological observations of the fetal lungs showed marked distortion of the normal lung cytoarchitecture in the treated groups compared to the control. These results suggest that doses of 150 mg/kg and 250 mg/kg body weight of the leaf extract of Rauwolfia vomitoria may cause intrauterine growth acceleration and may be pneumotoxic to the developing rat's lungs with the effect being dose dependent

Redispersible liposomal-N-acetylcysteine powder for pulmonary administration: Development, in vitro characterization and antioxidant activity

Liposomal dry powders of N-acetylcysteine (SD-NAC-Lip) were developed for pulmonary administration. Liposomes were prepared by reverse phase evaporation and spray dried using lactose (10%, w/w) as drying adjuvant. The powders were characterized according to process yield, drug content, residual water content, particle size distribution, morphology and redispersion behavior. In vitro aerosol performance was evaluated using an eight-stage Andersen Cascade Impactor. Moreover, in vitro antioxidant activity was determined by measuring thiobarbituric acid reactive species (TBARS) present in the lungs of healthy Wistar rats after induction of oxidation by iron/EDTA. The spray-drying process had a high yield (71%±2), drug content (mg/g) according to the expected value, moisture content below 9%, geometric mean diameter under 3μm with span value lower than 1. Spherical particles were observed by scanning electron microscopy. Liposomal dry-powders were able to recover the nanometric size of the original dispersion after their redispersion in aqueous medium, as shown by laser diffraction and transmission electron microscopy. Furthermore, the powders presented aerodynamic diameter of about 7μm and respirable fraction above 30%, indicating suitable properties for pulmonary use. The encapsulation of N-acetylcysteine in liposomes was essential to maintain its in vitro antioxidant activity after the drying process. In addition, the powder containing the encapsulated drug had better in vitro antioxidant activity than the liquid and solid formulations containing the non-encapsulated drug, which makes it a good candidate for the treatment of pulmonary diseases associated with oxidative stress.

Histophysiology of the Immune System of Wistar Rats at Delayed Terms after Ovariectomy

We studied histophysiological changes in organs of the immune system, liver, and lungs of Wistar rats at delayed terms after ovariectomy. On day 52 after surgical castration leading to a decrease in estradiol, progesterone, and testosterone levels, activation of the immune system was revealed characterized by stage I accidental thymus involution, while pulp depletion in the spleen, and enhanced IL-2 and IFN-γ production. We also observed small-droplet degeneration of hepatocytes and reactive changes in the lungs manifested in increased number of neutrophils in the interalveolar septa.

Increase of bone morphogenetic protein-7 expressing pulmonary resident cells in pneumonectomized rats

Compensatory lung growth (CLG) is recognized in rodents subjected to major pulmonary resection; however, the source of cells constituting regenerated tissues during the CLG is still unknown. We investigated the differentiation of lung resident cells and the participation of bone marrow (BM)-derived cells in the remnant lung of pneumonectomized rats. After left pneumonectomy, the right remnant lung of Wistar rats was subjected to morphologic and molecular experiments at several time points. We studied the expression of bone morphogenic protein 7 (BMP-7), an accelerator of epithelial differentiation, based on the gene expression profile data of the remnant lung. Next, we evaluated the presence of GFP-positive cells in the remnant lung of Wistar rats that had received BM transplantation from green fluorescent protein (GFP) gene-transgenic Wistar rats prior to left pneumonectomy. We observed progression of emphysematous change, modulation of gene expression profile, and proliferating cellular nuclear antigen-positive cells in the alveoli of the remnant lungs. BMP-7 protein positive cells were detected in the alveolar septa, which increased significantly over time with the progression of emphysematous change. No bone marrow-derived cells were detected in the right remnant lung of the GFP-BM transferred rats by fluorescence microscopy, immunohistochemistry, or polymerase chain reaction at any time. Lung resident cells appear to contribute to CLG, possibly via a trans-differentiation pathway.

Effects of Aluminium Chloride Exposure on the Histology of lungs of Wistar Rats

Aluminium is ubiquitous element and the third most prevalent (abundant) element in the earth's crust. It is presents in many manufactured foods, medicines and is also added to drinking water for purification purposes. The purpose of this study was to evaluate the effects of aluminium chloride exposure on the histology of kidney of wistar rats. Twenty (20) adult wistar rats were used for this study. The animals were divided into five groups as follows: group I was the control that received distil water only, group II received 475mg kg -1 , group III received 950mgkg -1 , group IV received 1,425mg kg -1 and group V received 1,900mg kg -1 via oral intubation for duration of eight weeks. The wistar rats were humanely sacrificed and kidneys were removed and fixed in formalin. The kidneys were processed and stained using the routine haematoxylin and eosin staining method (H&E). The stained sections were examined under the light microscope fitted to a digital camera. Our results showed cavitations, glomerular atrophy and vacuolation of cytoplasm of the lining cells of both the proximal convoluted tubules (PCT) and distal convoluted tubules of the kidney in the treated groups when compared to the control group. Based on our observations, we therefore conclude that aluminium chloride exposure had detrimental effects on the histology of kidney of wistar rats.