scholarly journals Masseter Muscular Weakness Affects Temporomandibular Synovitis Induced by Jaw Opening in Growing Rats

2008 ◽  
Vol 78 (5) ◽  
pp. 819-825 ◽  
Author(s):  
Miho Ozaki ◽  
Sawa Kaneko ◽  
Kunimichi Soma
Keyword(s):  
Growth Period ◽  
Control Group ◽  
Tissue Samples ◽  
Synovial Hyperplasia ◽  
Jaw Opening ◽  
Male Wistar Rats ◽  
Cox 2 ◽  
Oxide Synthase ◽  
Inflammatory Changes ◽  
Masseter Muscles

Abstract Objective: To evaluate the influence of impaired masseter function during growth on the development of temporomandibular synovitis. Materials and Methods: Sixteen 3-week-old male Wistar rats were classified into four groups. The first group served as control; and in the second group, jaw opening was forced for 3 hours when the rats were 9 weeks old. In the third and fourth groups, the masseter muscles were bilaterally resected at 3 weeks of age, and the rats in the fourth group were additionally forced to open their jaw at 9 weeks of age. All rats were sacrificed at 9 weeks. Temporomandibular joint (TMJ) tissue samples were processed for histology, and evaluated for cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expressions by immunohistochemistry to examine the inflammatory changes in the synovial membrane. Results: The control group showed noninflammatory changes. In the jaw-opening group, vascular dilation and weak COX-2 immunoreactivity were induced by jaw opening in the synovium. In the masseter-resection group, the masseter-resected rats exhibited moderate synovial changes while in the resection with opening group, the masseter-resected rats revealed more significant inflammatory changes including synovial hyperplasia, dilated vasculature, fibrin deposits, and intense immunoreactivity for COX-2 and iNOS, all caused by jaw opening. Conclusions: These results suggest that masseter activity in the growth period is an important factor in the induction of temporomandibular synovitis.

scholarly journals Functional Changes of Temporomandibular Joint Mechanoreceptors Induced by Reduced Masseter Muscle Activity in Growing Rats

2009 ◽  
Vol 79 (5) ◽  
pp. 978-983 ◽  
Author(s):  
Takayoshi Ishida ◽  
Tadachika Yabushita ◽  
Kunimichi Soma
Keyword(s):  
Temporomandibular Joint ◽  
Muscle Activity ◽  
Masseter Muscle ◽  
Growth Period ◽  
Control Group ◽  
Functional Changes ◽  
Male Wistar Rats ◽  
Masseter Muscles ◽  
Experimental Group ◽  
Indirect Stimulation

Abstract Objective: To determine the influence of masseter muscle activity during growth on the functional characteristics of temporomandibular joint (TMJ) mechanoreceptors. Materials and Methods: Sixty-six 3-week-old male Wistar rats were divided into an experimental group, in which the masseter muscles were bilaterally resected at 3 weeks of age, and a control group. Single-unit activities of the TMJ mechanoreceptors were evoked by indirect stimulation of passive jaw movement. Electrophysiologic recordings of TMJ units were made at 5, 7, and 9 weeks of age. Results: During this period, the firing threshold of the TMJ units was significantly lower and the maximum instantaneous frequency of the TMJ units was significantly higher in the experimental group than in the control group. Conclusion: Reduced masseter activity during the growth period alters the response properties of TMJ mechanoreceptors.

Effects of chronic inhibition of inducible nitric oxide synthase in hyperthyroid rats

2005 ◽  
Vol 288 (6) ◽  
pp. E1252-E1257 ◽  
Author(s):  
Isabel Rodríguez-Gómez ◽  
Rosemary Wangensteen ◽  
Juan Manuel Moreno ◽  
Virginia Chamorro ◽  
Antonio Osuna ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Nitric Oxide Synthase ◽  
Inducible Nitric Oxide Synthase ◽  
Control Group ◽  
Hemodynamic Variable ◽  
Male Wistar Rats ◽  
Oxide Synthase ◽  
Inos Inhibition ◽  
Inducible Nitric Oxide

We hypothesized that nitric oxide generated by inducible nitric oxide synthase (iNOS) may contribute to the homeostatic role of this agent in hyperthyroidism and may, therefore, participate in long-term control of blood pressure (BP). The effects of chronic iNOS inhibition by oral aminoguanidine (AG) administration on BP and morphological and renal variables in hyperthyroid rats were analyzed. The following four groups ( n = 8 each) of male Wistar rats were used: control group and groups treated with AG (50 mg·kg−1·day−1, via drinking water), thyroxine (T4, 50 μg·rat−1·day−1), or AG + T4. All treatments were maintained for 3 wk. Tail systolic BP and heart rate (HR) were recorded weekly. Finally, we measured BP (mmHg) and HR in conscious rats and morphological, plasma, and renal variables. T4 administration produced a small BP (125 ± 2, P < 0.05) increase vs. control (115 ± 2) rats. AG administration to normal rats did not modify BP (109 ± 3) or any other hemodynamic variable. However, coadministration of T4 and AG produced a marked increase in BP (140 ± 3, P < 0.01 vs. T4). Pulse pressure and HR were increased in both T4- and T4 + AG -treated groups without differences between them. Plasma NOx (μmol/l) were increased in the T4 group (10.02 ± 0.15, P < 0.05 vs. controls 6.1 ± 0.10), and AG reduced this variable in T4-treated rats (6.81 ± 0.14, P < 0.05 vs. T4) but not in normal rats (5.78 ± 0.20). Renal and ventricular hypertrophy and proteinuria of hyperthyroid rats were unaffected by AG treatment. In conclusion, the results of the present paper indicate that iNOS activity may counterbalance the prohypertensive effects of T4.

scholarly journals Renoprotective Effect of Fucoidan from Seaweed Sargassum angustifolium C. Agardh 1820 on Gentamicin-Induced Nephrotoxicity: From Marine Resources to Therapeutic Uses

2021 ◽  
Vol In Press (In Press) ◽  
Author(s):  
Khalil Pourkhalili ◽  
Zeinab Karimi ◽  
Mohammad Reza Farzaneh ◽  
Elham Ehsandoost ◽  
Mehdi Mohammadi ◽  
...  
Keyword(s):  
Urine Volume ◽  
Renal Tissue ◽  
Sulfated Polysaccharides ◽  
Control Group ◽  
Sod Activity ◽  
Tissue Samples ◽  
Therapeutic Uses ◽  
Male Wistar Rats ◽  
Sargassum Angustifolium ◽  
First Time

Background: Nephrotoxicity is a major side effect of aminoglycoside antibiotics, caused by oxidative damage and inflammation. Fucoidan, a group of sulfated polysaccharides derived from different species of brown algae, are well recognized for their antioxidant and anti-inflammatory activities. Objectives: In the present study, we aimed to investigate, for the first time, the efficacy of fucoidan extracted from Sargassum angustifolium C. Agardh 1820 against gentamicin-induced nephrotoxicity in rats. Methods: Twenty-eight male Wistar rats were divided into 4 groups of control, gentamicin (100 mg/kg), and gentamicin plus 50- and 100-mg/kg/day fucoidan pretreatment. In the end, all rats were killed, and then urine, blood, and tissue samples were prepared. Kidney weight (KW), body weight (BW), and 24-hour urine volume, as well as serum creatinine (Cr), blood urea nitrogen (BUN), Cr clearance, and malondialdehyde (MDA) levels and superoxide dismutase (SOD) activity, were measured. Kidney samples were also evaluated for histopathological changes. Results: Gentamicin significantly increased KW, KW/BW ratio, 24-hour urine volume, serum Cr, MDA, and BUN levels; however, fucoidan pretreatment, especially at a dose of 50 mg/kg, significantly returned these variables near to the control group values. Gentamicin also decreased BW gain, Cr clearance, SOD activity, and the degree of renal tissue damage compared to the control group, while treatment with fucoidan significantly reversed these alterations. Conclusions: The results show that fucoidan from S. angustifolium C. Agardh 1820 ameliorates gentamicin-induced nephrotoxicity by alleviating oxidative stress and augmenting antioxidant enzymes activity in renal tissue, suggesting the potential use of this fucoidan in a clinical setting.

scholarly journals Activated ROCK/Akt/eNOS and ET-1/ERK pathways in 5-fluorouracil-induced cardiotoxicity: modulation by simvastatin

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Radwa Nasser Muhammad ◽  
Nada Sallam ◽  
Hanan Salah El-Abhar
Keyword(s):  
Cell Function ◽  
Coronary Artery Spasm ◽  
Rho Kinase ◽  
Control Group ◽  
Endothelial Cell Function ◽  
Extracellular Signal ◽  
Phosphorylated Akt ◽  
Male Wistar Rats ◽  
Cox 2 ◽  
Group 5

Abstract 5-Fluorouracil (5-FU) is used in the treatment of different solid tumors; however, its use is associated with rare, but serious cardiotoxicity. Nevertheless, the involvement of ROCK/NF-κB, Akt/eNOS and ET-1/ERK1/2 trajectories in the cardiotoxic effect and in the potential cardioprotective upshot of simvastatin has been elusive. Male Wistar rats were allocated into 5-FU (50 mg/kg/week; i.p, 6 weeks), simvastatin (15 mg/kg/day; p.o, 8 weeks) treated groups and simvastatin + 5-FU, besides the normal control group. 5-FU-induced cardiotoxicity boosted the serum level of N-terminal pro-brain (B-type) natriuretic peptide (NT-proBNP), aortic contents of endothelin (ET)-1 and thromboxane (TX) A2, as well as cardiac contents of NADPH oxidases (Nox), cyclooxygenase (COX)-2, malondialdehyde (MDA), phosphorylated Akt (p-Akt), phosphorylated extracellular signal-regulated kinase (p-ERK)1/2 and the protein expressions of rho-kinase (ROCK) and caspase-3. On the other hand, it suppressed cardiac reduced glutathione (GSH) and phosphorylated endothelial nitric oxide synthase (p-eNOS). Contrariwise, co-administration with simvastatin overcame these disturbed events and modulated the ROCK/NF-κB, Akt/eNOS and ET-1/ERK1/2 signaling pathways. This study highlights other mechanisms than coronary artery spasm in the 5-FU cardiotoxicity and reveals that NT-proBNP is a potential early marker in this case. Moreover, the cross-talk between ROCK/ NF-κB, ROS/COX-2/TXA2, Akt/eNOS and ET-1/ERK1/2 pathways contributes via different means to upsetting the vasoconstriction/vasodilatation equilibrium as well as endothelial cell function and finally leads to cardiomyocyte stress and death—the modulation of these trajectories offers simvastatin its potential cardio-protection against 5-FU.

scholarly journals Micro-CT Analysis of Morphological Changes in Mandibles of Growing Rats with Unilateral Occlusal Elevation

2019 ◽  
Vol 13 (1) ◽  
pp. 150-158
Author(s):  
Takahiro Morohoshi ◽  
Takenobu Ishii ◽  
Munetada Ishikawa ◽  
Daehwan Choi ◽  
Dai Ariizumi ◽  
...  
Keyword(s):  
Morphological Changes ◽  
Three Dimensional ◽  
Growth Period ◽  
Control Group ◽  
Micro Computed Tomography ◽  
Growing Rats ◽  
Male Wistar Rats ◽  
Ct Analysis ◽  
Long Term Observation ◽  
Removal Group

Objectives: This study investigated the effect of unilateral occlusal elevation in the molar region on facial and mandibular development in growing rats. Materials and Methods: Thirty 5-week-old male Wistar rats were randomly allocated to three groups (n = 10). The control group was allowed to develop naturally until 9 weeks of age. A device fitted on the caused unilateral occlusal elevation at 5 weeks in the removal group. The device was removed at 7 weeks and the rats were observed until 9 weeks. In the continuation group, the same device fitted on the left-side molars caused unilateral occlusal elevation continuously for 9 weeks. All groups underwent craniofacial scanning with three-dimensional micro-computed tomography at 5, 7, and 9 weeks. Results: In the removal and continuation groups, the mandible was displaced to the unelevated side. At 7 weeks, both these groups showed greater skeletal growth and molar extrusion on the elevated side, with significant differences between the elevated and unelevated sides. At 9 weeks, there were significant differences in both skeletal and alveolar growth between these groups; the asymmetry ameliorated in the removal group. Limitations: We evaluated three-dimensional morphometry by fitting a device to rat molars for a short observation period; thus, future studies are warranted to acquire data following long-term observation. Conclusion: Unilateral occlusal elevation during the growth period suppressed molar eruption and extrusion on the elevated and unelevated sides, respectively. The height of the mandibular ramus increased on the elevated side, resulting in asymmetric growth.

scholarly journals Pulmonary emphysema induced by methylphenidate: experimental study

2015 ◽  
Vol 133 (2) ◽  
pp. 131-134 ◽  
Author(s):  
Gabriel Victor Guimarães Rapello ◽  
Andréia Antoniolli ◽  
Daniel Martins Pereira ◽  
Gilberto Facco ◽  
Paulo Manuel Pêgo-Fernandes ◽  
...  
Keyword(s):  
Experimental Study ◽  
Pulmonary Emphysema ◽  
Public University ◽  
Control Group ◽  
Tissue Samples ◽  
Hyperactivity Disorder ◽  
Male Wistar Rats ◽  
The Mean ◽  
Loss Of Appetite ◽  
Different Doses

CONTEXT AND OBJECTIVE: Methylphenidate is the most widely used drug for treating attention deficit hyperactivity disorder. However, it has important side effects, such as abdominal pain, insomnia, anorexia and loss of appetite, and also some cases of early severe emphysema after drug abuse have been reported. Our aim was to investigate the development of pulmonary emphysema in rats that were subjected to different doses of methylphenidate. DESIGN AND SETTING: Experimental study carried out at the laboratory of a public university. METHODS: Eighteen male Wistar rats were divided into three groups: control (0.9% saline solution); MP 0.8 (methylphenidate, 0.8 mg/kg); MP 1.2 (methylphenidate, 1.2 mg/kg). After 90 days of daily gavage, the animals were sacrificed and lung tissue samples were prepared for analysis on the mean alveolar diameter (Lm). RESULTS: The Lm was greater in MP 0.8 (47.91 ± 3.13; P < 0.01) and MP 1.2 (46.36 ± 4.39; P < 0.05) than in the control group (40.00 ± 3.48). CONCLUSION: Methylphenidate caused an increase in the alveolar diameter of rats, which was compatible with human pulmonary emphysema.

scholarly journals INHIBITION OF COX-2 EXPRESSION BY LUNASIN-RICH SOYBEAN EXTRACT ON COLORECTAL CANCER

2019 ◽  
pp. 116-121
Author(s):  
KUSMARDI KUSMARDI ◽  
VANNESSA KARENINA ◽  
ARI ESTUNINGTYAS ◽  
ARYO TEDJO
Keyword(s):  
Colorectal Cancer ◽  
Distal Colon ◽  
Negative Control Group ◽  
Negative Control ◽  
Colorectal Carcinogenesis ◽  
Control Group ◽  
Tissue Samples ◽  
Cell Counts ◽  
Soybean Extract ◽  
Cox 2

Objective: The incidence of colorectal cancer has been growing faster than most other cancers in the past decade, especially in developing countries. One of the substances that is currently being investigated as potential chemopreventive agent is lunasin, which is contained in soybeans. This research explored the effect of lunasin on COX-2 expression in the distal colons of mice in which colorectal carcinogenesis was induced with azoxymethane (AOM) and dextran sodium sulfate (DSS). Methods: A total of 30 Swiss Webster mice were separated into six groups. In five of the groups—a negative control group, positive control group, and three intervention groups—carcinogenesis was induced with AOM and DSS; the sixth group received no interventions. Lunasin-rich soybean extracts were given in doses of 250, 300, and 350 mg/kgBW for 6 w to the intervention groups Immunohistochemical staining of COX-2 was then carried out on tissue samples from the distal colons of mice that had been sacrificed. The samples were microscopically assessed and photographed, and cell counts were performed using the Image J application. COX-2 expression is reported in the form of an optical density score (ODS). Results: Significant differences between the negative control and the intervention groups were found at the 300 mg/kgBW (p = 0.047) and 350 mg/kgBW (p = 0.016) lunasin dosage levels. Conclusions: This demonstrates that administration of lunasin-rich soy extracts can inhibit COX-2 expression in cryptic epithelial cells of the distal colon in mice with carcinogenesis induced by AOM and DSS.

The effect of Paracetamol exposure on hepatic and renal tissues during statin usage

2019 ◽  
Vol 44 (1) ◽  
pp. 113-120
Author(s):  
Saliha Aksun ◽  
Alpaslan Gökcimen ◽  
Fadime Kahyaoglu ◽  
Buket Demirci
Keyword(s):  
Drug Interaction ◽  
Combination Therapy ◽  
Male Rats ◽  
Control Group ◽  
Tissue Samples ◽  
Liver And Kidney ◽  
Statin Usage ◽  
Paracetamol Interaction ◽  
Oxide Synthase ◽  
Important Drug

Abstract Objective Statins and Paracetamol have widespread use in clinic and both drugs possess similar side effects; therefore, we investigated if drug-interaction occurs when the combination of these two drugs is used during therapy. Materials and methods A total of 32 (12–15 months old) grown-up male rats were divided into four groups: Control group, RSV group (10 mg/kg Rosuvastatin/daily), APAP group (50 mg/kg Paracetamol/5 days/weekly), RSV+APAP (10 mg/kg Rosuvastatin/daily+50 mg/kg Paracetamol/5 days/weekly). At the end of 8 weeks of chronic treatment, the blood and tissue samples were taken under the Ketamine and Xylasine anesthesia (50 mg/kg and 5 mg/kg, respectively). Results In the liver, sinusoidal dilatations, pyknotic nuclei and hemorrhagic foci are more frequently seen in the group receiving combination therapy; although serum liver functions among groups were not significantly different. Kidney histopathologic alterations in APAP and RSV+APAP groups were found more distinct than in RSV alone group. Inducible nitric oxide synthase activity was highly increased with combination therapy in liver and kidney tissues. Conclusion RSV-Paracetamol interaction may occur as an important drug interaction histopathologically even before it is manifested biochemically in the clinic.

scholarly journals Lung Histopathology in Baclofen Intoxication

2021 ◽  
Vol 17 (2) ◽  
pp. 37-44
Author(s):  
O. L. Romanova ◽  
D. V. Sundukov ◽  
M. A. Golubev ◽  
M. L. Blagonravov ◽  
A. V. Ershov
Keyword(s):  
Cellular Response ◽  
Control Group ◽  
Tissue Samples ◽  
Morphological Alterations ◽  
Bronchial Lumen ◽  
Lung Histopathology ◽  
Male Wistar Rats ◽  
Circulatory Disorders ◽  
Group 2 ◽  
Group 1

The aim of the study: to assess the lung histopathology in acute intoxication with baclofen alone and its combination with alcohol (in the same dose) 3 hours after the ingestion.Materials and methods. The study was performed on 15 male Wistar rats weighing 290-350 g and aged 20 weeks. The animals were divided into 3 groups, 5 animals each: control group that included intact rats; Group 1 composed of rats received baclofen alone; Group 2 that included rats received a combination of baclofen and ethanol. Baclofen was administered orally at a dose of 85 mg/kg animal weight under anesthesia (chloralose), and 40% ethanol, 7 ml/kg animal weight, was orally administered along with baclofen at the same dose. Animals of all groups were sacrificed after 3 hours by overdosing anesthetic agent. Lung tissue samples were examined by light microscopy using a video system at x400 magnification. The following histological characteristics were evaluated: circulatory disorders (engorged capillaries and venules, hemorrhages in interalveolar septa and alveoli, sludge), atelectasis (including partial), emphysema, cellular response (increased WBCs in the interalveolar septal area), thickening of interalveolar septa due to edema, epithelial desquamation into bronchial lumen. The diameter of alveoli and thickness of interalveolar septa were measured.Results. Three hours after the baclofen administration, circulatory disorders in the lungs (engorged venules and capillaries, hemorrhages in the interalveolar septa, sludge), emphysema, atelectasis (complete and partial) as well as cellular response (leucocyte infiltration of interalveolar septa) were detected. In the Group 2, baclofen resulted in circulatory disorders (engorged venules and capillaries, sludge), emphysema, atelectasis (complete and incomplete), cellular response (infiltration with leukocytes), as well as fluid in the lumen of bronchioles. In Group 1, the alveolar diameter was significantly larger than in the control group and Group 2, while the thickness of the interalveolar septa was lower. In group 2, alveolar diameter was significantly less than in group 1, but still greater than in the control group. The thickness of the interalveolar septa in group 2 was significantly greater than in the control group and group 1.Conclusion. After administration of baclofen alone and in combination with ethanol, the following alterations were found in the lungs: circulation disorders (venular and capillary engorgement, sludge), increased vascular permeability because of developing hypoxia, leukocyte infiltration of interalveolar septa. The monitoring of morphological alterations may aid in evaluating the severity of pathological processes in intoxication with baclofen alone and in combination with ethanol and in determining the method of intoxication (baclofen alone or in combination with ethanol).

scholarly journals Correlation between pain and hyalinization during tooth movement induced by different types of force

2019 ◽  
Vol 89 (5) ◽  
pp. 788-796 ◽  
Author(s):  
Osmar A. Cuoghi ◽  
Francielle Topolski ◽  
Lorraine P. de Faria ◽  
Edilson Ervolino ◽  
Kelly R. Micheletti ◽  
...  
Keyword(s):  
Tooth Movement ◽  
Interleukin 1 ◽  
Control Group ◽  
Positive Correlation ◽  
Male Wistar Rats ◽  
Moderate Negative Correlation ◽  
Cox 2 ◽  
Tissue Reactions ◽  
Moderate Positive Correlation ◽  
Chemical Mediators

ABSTRACT Objectives: To evaluate the correlation between pain and tissue reactions during induced tooth movement (ITM). Materials and Methods: Forty-two male Wistar rats (Rattus norvegicus; ∼90 days of age, 300 g) were used. The animals were divided into seven groups of six rats each: one control group and six experimental groups subjected to ITM by continuous force (CF) or interrupted continuous force (ICF) for 1, 3, and 5 days. Hyalinization of the periodontal ligament (PL) and occurrence of pain were observed. Animal behavior (walking, climbing, immobile posture, resting/sleeping, and directed face grooming) and the presence of chemical mediators associated with nociception, cyclooxygenase-2 (COX-2), and interleukin-1 beta (IL-1β) in the PL were analyzed. Results: There was a moderate positive correlation between hyalinization and the presence of COX-2 (rs = 0.404; P &lt; .05) and IL-1β (rs = 0.429; P &lt; .05). There was a moderate negative correlation between hyalinization and exploratory behaviors (walking, r = −0.586, P &lt; .01; climbing, r = −0.573, P &lt; .01), and a moderate positive correlation between hyalinization and resting/sleeping (r = 0.467; P &lt; .01). Conclusions: The results suggest a correlation between pain and undesirable tissue reactions in ITM.

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