Histological analysis of the effects of cadmium, chromium and mercury alone and in combination on the spleen of male Sprague-Dawley rats

Previous studies have shown that newborn rats exposed postnatally to hyperoxia will develop a permanent impairment of the retinal function as determined with the electroretinogram (ERG). The purpose of our study was to examine whether postnatal hyperoxia equally alters the light- and dark-adapted ERGs and oscillatory potentials (OPs) as well as leads to permanent structural modification of the retina. During the first 14 days of life, cohorts of Sprague-Dawley rats were exposed to a hyperoxic environment, and ERGs were recorded at mean ages of approximately 25 and 55 days. Our results indicate that both light- and dark-adapted ERGs and OPs are already significantly altered within a few days following exposure to hyperoxia. None of the ERG and (or) OP parameters, with the exception of the a-wave, returned to normal values by 55 days of age. In fact some dark-adapted OPs were completely abolished following postnatal O2 exposure. Histological analysis revealed that the retina of rats exposed to hyperoxia failed to develop an outer plexiform layer and had a reduced count of horizontal cells, consistent with the permanent postreceptoral anomalies seen in the ERG responses. Our results suggest that postnatal hyperoxia causes a generalized retinal disorder leading to permanent structural modifications of the retinal cytoarchitecture and lasting anomalies of the rod and cone functions.Key words: rods, cones, electroretinography, oscillatory potentials, hyperoxia, retina, development.

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Histological analysis of different local haemostatic agents used for periapical surgery: An experimental study with Sprague‐Dawley rats

Australian Endodontic Journal ◽

10.1111/aej.12332 ◽

2019 ◽

Vol 45 (3) ◽

pp. 357-364

Author(s):

Jesús Mena‐Álvarez ◽

Norberto Quispe‐López ◽

Álvaro Zubizarreta‐Macho ◽

Cristina Rico‐Romano ◽

Rosa Rodero‐Villanueva ◽

...

Keyword(s):

Experimental Study ◽

Histological Analysis ◽

Sprague Dawley ◽

Sprague Dawley Rats ◽

Haemostatic Agents

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Diabetes increases brain damage caused by severe hypoglycemia

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.91041.2008 ◽

2009 ◽

Vol 297 (1) ◽

pp. E194-E201 ◽

Cited By ~ 72

Author(s):

Adam J. Bree ◽

Erwin C. Puente ◽

Dorit Daphna-Iken ◽

Simon J. Fisher

Keyword(s):

Brain Damage ◽

Histological Analysis ◽

Neuronal Damage ◽

Severe Hypoglycemia ◽

Hippocampal Damage ◽

Sprague Dawley ◽

Brain Areas ◽

Sprague Dawley Rats ◽

Brain Tissue Damage ◽

Extent Of Damage

Insulin-induced severe hypoglycemia causes brain damage. The hypothesis to be tested was that diabetes portends to more extensive brain tissue damage following an episode of severe hypoglycemia. Nine-week-old male streptozotocin-diabetic (DIAB; n = 10) or vehicle-injected control (CONT; n = 7) Sprague-Dawley rats were subjected to hyperinsulinemic (0.2 U·kg−1·min−1) severe hypoglycemic (10–15 mg/dl) clamps while awake and unrestrained. Groups were precisely matched for depth and duration (1 h) of severe hypoglycemia (CONT 11 ± 0.5 and DIAB 12 ± 0.2 mg/dl, P = not significant). During severe hypoglycemia, an equal number of episodes of seizure-like activity were noted in both groups. One week later, histological analysis demonstrated extensive neuronal damage in regions of the hippocampus, especially in the dentate gyrus and CA1 regions and less so in the CA3 region ( P < 0.05), although total hippocampal damage was not different between groups. However, in the cortex, DIAB rats had significantly (2.3-fold) more dead neurons than CONT rats ( P < 0.05). There was a strong correlation between neuronal damage and the occurrence of seizure-like activity ( r2 > 0.9). Separate studies conducted in groups of diabetic ( n = 5) and nondiabetic ( n = 5) rats not exposed to severe hypoglycemia showed no brain damage. In summary, under the conditions studied, severe hypoglycemia causes brain damage in the cortex and regions within the hippocampus, and the extent of damage is closely correlated to the presence of seizure-like activity in nonanesthetized rats. It is concluded that, in response to insulin-induced severe hypoglycemia, diabetes uniquely increases the vulnerability of specific brain areas to neuronal damage.

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Optimization of Complete Rat Heart Decellularization Using Artificial Neural Networks

Micromachines ◽

10.3390/mi13010079 ◽

2022 ◽

Vol 13 (1) ◽

pp. 79

Author(s):

Greta Ionela Barbulescu ◽

Taddeus Paul Buica ◽

Iacob Daniel Goje ◽

Florina Maria Bojin ◽

Valentin Laurentiu Ordodi ◽

...

Keyword(s):

Neural Networks ◽

Histological Analysis ◽

Sodium Dodecyl ◽

Sprague Dawley ◽

Deep Convolutional Neural Networks ◽

Software Application ◽

Sprague Dawley Rats ◽

Machine Learning Approach ◽

Image Set ◽

Exact Moment

Whole organ decellularization techniques have facilitated the fabrication of extracellular matrices (ECMs) for engineering new organs. Unfortunately, there is no objective gold standard evaluation of the scaffold without applying a destructive method such as histological analysis or DNA removal quantification of the dry tissue. Our proposal is a software application using deep convolutional neural networks (DCNN) to distinguish between different stages of decellularization, determining the exact moment of completion. Hearts from male Sprague Dawley rats (n = 10) were decellularized using 1% sodium dodecyl sulfate (SDS) in a modified Langendorff device in the presence of an alternating rectangular electric field. Spectrophotometric measurements of deoxyribonucleic acid (DNA) and total proteins concentration from the decellularization solution were taken every 30 min. A monitoring system supervised the sessions, collecting a large number of photos saved in corresponding folders. This system aimed to prove a strong correlation between the data gathered by spectrophotometry and the state of the heart that could be visualized with an OpenCV-based spectrometer. A decellularization completion metric was built using a DCNN based classifier model trained using an image set comprising thousands of photos. Optimizing the decellularization process using a machine learning approach launches exponential progress in tissue bioengineering research.

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Abstract 262: A Rat Model of Heart Failure With Preserved Ejection Fraction Induced by Pressure Overload

Circulation Research ◽

10.1161/res.119.suppl_1.262 ◽

2016 ◽

Vol 119 (suppl_1) ◽

Author(s):

Shu-Yu Sun ◽

Barry Campbell ◽

Valdeci Da Cunha ◽

Xuening Hong ◽

Chin-hu Huang ◽

...

Keyword(s):

Histological Analysis ◽

Potential Model ◽

Pressure Overload ◽

Preserved Ejection Fraction ◽

Sprague Dawley ◽

Aortic Banding ◽

Clinical Phenotypes ◽

Novel Treatments ◽

Sprague Dawley Rats ◽

Invasive Hemodynamics

The absence of animal models displaying clinical phenotypes of HFpEF represents a challenge to the pharmaceutical industry in the hope of identifying novel treatments that would benefit patients with this syndrome. We, at Merck, examined the supracoronary aortic banding (SAB) in rats as a potential model and set out to characterize its phenotypes. Juvenile Sprague-Dawley rats were used; a hemostatic clip with an opening of 0.7 mm was placed around the ascending aorta to elicit a pressure overload to the LV. Echocardiography was performed every 3 weeks and invasive hemodynamics was measured at week 9 to evaluate cardiac structural and functional effects; heart and lungs were harvested at the end for morphological and histological analysis. Nine weeks after SAB, LV hypertrophy and dysfunction were apparent, as manifested by increases in LVEDP, left atrial pressure, plasma BNP, LV and lung weights; LV relaxation time constant (Tau) and mitral early to late inflow ratio (E/A) were also increased; while EF and FS were preserved (see table, mean ± SEM). In addition, SAB rats had elevated mean pulmonary pressure (sham 14 ± 1.7 vs. SAB 37 ± 4.4 mm Hg, p<0.05) with an abnormal transpulmonary gradient (sham 12 ± 2.5 vs. SAB 23 ± 0.1 mm Hg, p<0.05), indicating comorbidity of pulmonary hypertension. Finally, piloerection, dyspnea and loss of muscle mass were evident and exercise tolerance measured by treadmill test was decreased in SAB rats. In summary, rats undergoing SAB exhibit many of the clinical phenotypes of HFpEF. Further work includes examining the effects of novel therapies in SAB rats on improving these clinical phenotypes of HFpEF and expanding the model to study morbidity and mortality.

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Influence on Bone-to-Implant Contact of Non-Thermal Low-Pressure Argon Plasma: An Experimental Study in Rats

Applied Sciences ◽

10.3390/app10093069 ◽

2020 ◽

Vol 10 (9) ◽

pp. 3069

Author(s):

Arturo Sanchez-Perez ◽

Ana I. Nicolas-Silvente ◽

Carmen Sanchez-Matas ◽

Fernando Muñoz-Guzon ◽

Carlos Navarro-Cuellar ◽

...

Keyword(s):

Essential Role ◽

Histological Analysis ◽

Bacterial Colonization ◽

Argon Plasma ◽

Low Pressure ◽

Sprague Dawley ◽

New Techniques ◽

Implant Placement ◽

Sprague Dawley Rats ◽

Bone To Implant Contact

Roughness characteristics play an essential role in osseointegration. However, there is a concern about the susceptibility of those surfaces to bacterial colonization. New techniques for cleaning and surface treatment have appeared that could favor osseointegration without the need to create surfaces as rough. Such is the case of non-thermal low-pressure argon plasma (NTLP-ArP). One hundred and forty-four implants were placed in the tibiae of 36 Sprague Dawley rats, distributed in four experimental groups: I: mechanized surface; II: mechanized surface treated with NTLP-ArP, III: resorbable blast media (RBM) surface; and IV: RBM surface treated with (NTLP-ArP). Bone-to-implant contact (BIC) percentages were calculated by microtomographic evaluation and histological analysis at one, two, and four weeks after implant placement. ANOVA and Mann–Whitney tests were used for statistical analysis, establishing p < 0.05. No significant differences were found at one-week comparisons. The groups treated with NTLP-ArP obtained higher BIC% than those not treated at two and four weeks. Mechanized surfaces treated with NTLP-ArP obtained BIC values similar to RBM surfaces.

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Corticotomy depth and regional acceleratory phenomenon intensity:

The Angle Orthodontist ◽

10.2319/041320-296.1 ◽

2020 ◽

Author(s):

Jeremy R. Kernitsky ◽

Taisuke Ohira ◽

Dhurata Shosho ◽

June Lim ◽

Abdullah Bamashmous ◽

...

Keyword(s):

Histological Analysis ◽

Cone Beam ◽

Deep Penetration ◽

Sprague Dawley ◽

Collagen Formation ◽

Sprague Dawley Rats ◽

Computed Tomography Scans ◽

Group A ◽

Regional Acceleratory Phenomenon ◽

The Right

ABSTRACT Objectives To determine if the depth of corticotomy done with the piezoelectric knife could play a role in the intensity of the regional acceleratory phenomenon (RAP). Materials and Methods Eighteen Sprague-Dawley rats were divided into two groups: untreated (3 rats) and treatment (15 rats). In the treatment group, a split-model design was used. The right tibia received transcortical (deep) penetrations with the piezoelectric knife, while intracortical (shallow) penetrations were performed on the left tibia of the same animal. The rats were euthanized at day 1, 3, 7, 14, and 28. Cone-beam computed tomography scans were taken for each sample and then assessed by histological analysis. Results Higher amounts of osteoclastic activity and new collagen formation were observed in the deep penetration group when compared with the shallow penetration group. The former peaked at day 14 for both groups (1.53% ± 0.01% vs 0.03% ± 0.0004%, respectively), and the latter peaked at day 28 (0.65 × 106 ± 0.01 vs 0.08 × 106 ± 0.0008, respectively). Conclusions Within the limitations of this study, it appears that the intensity of the RAP in the rat is corticotomy depth dependent. This is to be kept in mind when decorticating the bone during surgically facilitated orthodontic procedures.

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Gordon Dry Gin (Moringa Citrus Blend) Induce Adenomatous Hyperplasia in Female Sprague Dawley Rats

Journal of Advances in Medicine and Medical Research ◽

10.9734/jammr/2019/v31i130276 ◽

2019 ◽

pp. 1-7

Author(s):

E. U. Eric ◽

T. O. Alade ◽

E. F. Eruvwahwe

Keyword(s):

Histological Analysis ◽

Negative Control ◽

Female Rats ◽

Sprague Dawley ◽

Adenomatous Hyperplasia ◽

Rat Uterus ◽

Sprague Dawley Rats ◽

Group A ◽

Group D ◽

Histopathological Effects

Objectives: This study aim to investigate the histopathological effects of binge consumed Gordon’s dry gin moringa citrus blend on the uterus of adult female dawley Sprague rats. Materials: Fifty female rats (weighing range; 120±2.6 g - 250±3.5 g) were divided into four groups (A, B and C & D). Group A, B, C (15 animals each) were orally administered with Gordon’s dry gin moringa citrus blend, 43% ethanol, and 200 mg/kg moringa extract, respectively, while Group D (5 animals) did not receive any treatment and was used as negative control. In groups A, B, and C, five animals were sacrificed on the 7th, 14th and 21st day of administration, whereas animals of group D were sacrificed on day 21. The uterus of each rat was harvested, processed and stained with haematoxylin and eosin solution for histological analysis. Results: Results of the study revealed histological alterations in the uterus of treated animals. Such alterations include adenomatous hyperplasia and cystic hyperplasia. Conclusion: The oral administration of gordon’s dry gin moringa citrus and moringa extract at 200 mg/kg induced cystic and adenomatous hyperplasia in rat uterus, inferring that both gordon dry gin and moringa might yield antifertility activity.

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Ultrastructural Investigation of Spontaneous Pituitary Adenomas in Aging Sprague-Dawley Rats

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100053747 ◽

1982 ◽

Vol 40 ◽

pp. 216-217

Author(s):

D. J. McComb ◽

J. Beri ◽

F. Zak ◽

K. Kovacs

Keyword(s):

Microscopic Study ◽

Pituitary Adenomas ◽

Wistar Rats ◽

Microscopic Level ◽

Sprague Dawley ◽

Prolactin Cells ◽

Light Microscopic Level ◽

Ultrastructural Investigation ◽

Sprague Dawley Rats ◽

Long Evans

Investigation of the spontaneous pituitary adenomas in rat have been limited mainly to light microscopic study. Furth et al. (1973) described them as chromophobic, secreting prolactin. Kovacs et al. (1977) in an ul trastructural investigation of adenomas of old female Long-Evans rats, found that they were composed of prolactin cells. Berkvens et al. (1980) using immunocytochemistry at the light microscopic level, demonstrated that some spontaneous tumors of old Wistar rats could contain GH, TSH or ACTH as well as PRL.

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Early Development of Drug-Induced Hepatic Necrosis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100066942 ◽

1971 ◽

Vol 29 ◽

pp. 576-577

Author(s):

F. G. Zaki ◽

E. Detzi ◽

C. H. Keysser

Keyword(s):

Early Development ◽

Hepatic Necrosis ◽

Screening Tests ◽

Dense Matrix ◽

Sprague Dawley ◽

Electron Microscopic ◽

Drug Induced ◽

Hepatocellular Damage ◽

Sprague Dawley Rats ◽

Microscopic Studies

This study represents the first in a series of investigations carried out to elucidate the mechanism(s) of early hepatocellular damage induced by drugs and other related compounds. During screening tests of CNS-active compounds in rats, it has been found that daily oral administration of one of these compounds at a dose level of 40 mg. per kg. of body weight induced diffuse massive hepatic necrosis within 7 weeks in Charles River Sprague Dawley rats of both sexes. Partial hepatectomy enhanced the development of this peculiar type of necrosis (3 weeks instead of 7) while treatment with phenobarbital prior to the administration of the drug delayed the appearance of necrosis but did not reduce its severity.Electron microscopic studies revealed that early development of this liver injury (2 days after the administration of the drug) appeared in the form of small dark osmiophilic vesicles located around the bile canaliculi of all hepatocytes (Fig. 1). These structures differed from the regular microbodies or the pericanalicular multivesicular bodies. They first appeared regularly rounded with electron dense matrix bound with a single membrane. After one week on the drug, these vesicles appeared vacuolated and resembled autophagosomes which soon developed whorls of concentric lamellae or cisterns characteristic of lysosomes (Fig. 2). These lysosomes were found, later on, scattered all over the hepatocytes.

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