Evaluation of the impact of transgenic maize BT799 on growth, development and reproductive function of Sprague-Dawley rats in three generations

Abstract Objective: Whereas numerous experimental and clinical studies suggest a complex involvement of serotonin in the regulation of anxiety, it remains to be clarified if the dominating impact of this transmitter is best described as anxiety-reducing or anxiety-promoting. The aim of this study was to assess the impact of serotonin depletion on acquisition, consolidation, and expression of conditioned fear. Methods: Male Sprague–Dawley rats were exposed to foot shocks as unconditioned stimulus and assessed with respect to freezing behaviour when re-subjected to context. Serotonin depletion was achieved by administration of a serotonin synthesis inhibitor, para-chlorophenylalanine (PCPA) (300 mg/kg daily × 3), (i) throughout the period from (and including) acquisition to (and including) expression, (ii) during acquisition but not expression, (iii) after acquisition only, and (iv) during expression only. Results: The time spent freezing was significantly reduced in animals that were serotonin-depleted during the entire period from (and including) acquisition to (and including) expression, as well as in those being serotonin-depleted during either acquisition only or expression only. In contrast, PCPA administrated immediately after acquisition, that is during memory consolidation, did not impact the expression of conditioned fear. Conclusion: Intact serotonergic neurotransmission is important for both acquisition and expression of context-conditioned fear.

Download Full-text

Short-Term High Fat Intake Does Not Significantly Alter Markers of Renal Function or Inflammation in Young Male Sprague-Dawley Rats

Journal of Nutrition and Metabolism ◽

10.1155/2015/157520 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 4

Author(s):

Catherine Crinigan ◽

Matthew Calhoun ◽

Karen L. Sweazea

Keyword(s):

Kidney Disease ◽

Renal Mass ◽

Early Stage ◽

Young Male ◽

Protective Effects ◽

Sprague Dawley ◽

High Fat ◽

Short Term ◽

Sprague Dawley Rats ◽

The Impact

Chronic high fat feeding is correlated with diabetes and kidney disease. However, the impact of short-term high fat diets (HFD) is not well-understood. Six weeks of HFD result in indices of metabolic syndrome (increased adiposity, hyperglycemia, hyperinsulinemia, hyperlipidemia, hyperleptinemia, and impaired endothelium-dependent vasodilation) compared to rats fed on standard chow. The hypothesis was that short-term HFD would induce early signs of renal disease. Young male Sprague-Dawley rats were fed either HFD (60% fat) or standard chow (5% fat) for six weeks. Morphology was determined by measuring changes in renal mass and microstructure. Kidney function was measured by analyzing urinary protein, creatinine, and hydrogen peroxide (H2O2) concentrations, as well as plasma cystatin C concentrations. Renal damage was measured through assessment of urinary oxDNA/RNA concentrations as well as renal lipid peroxidation, tumor necrosis factor alpha (TNFα), and interleukin 6 (IL-6). Despite HFD significantly increasing adiposity and renal mass, there was no evidence of early stage kidney disease as measured by changes in urinary and plasma biomarkers as well as histology. These findings suggest that moderate hyperglycemia and inflammation produced by short-term HFD are not sufficient to damage kidneys or that the ketogenic HFD may have protective effects within the kidneys.

Download Full-text

The Effects of Feed Restriction on Reproductive Function in Sprague-Dawley Rats

Fundamental and Applied Toxicology ◽

10.1006/faat.1993.1003 ◽

1993 ◽

Vol 20 (1) ◽

pp. 23-29 ◽

Cited By ~ 68

Author(s):

R Chapin

Keyword(s):

Reproductive Function ◽

Feed Restriction ◽

Sprague Dawley ◽

Sprague Dawley Rats

Download Full-text

Structural Alteration in Dermal Vessels and Collagen Bundles following Exposure of Skin Wound to Zeolite–Bentonite Compound

Journal of Pharmaceutics ◽

10.1155/2016/5843459 ◽

2016 ◽

Vol 2016 ◽

pp. 1-5 ◽

Cited By ~ 2

Author(s):

Shahram Paydar ◽

Ali Noorafshan ◽

Behnam Dalfardi ◽

Shahram Jahanabadi ◽

Seyed Mohammad Javad Mortazavi ◽

...

Keyword(s):

Healing Process ◽

Volume Density ◽

Skin Wound ◽

Sprague Dawley ◽

Small Vessels ◽

Sprague Dawley Rats ◽

Significant Difference ◽

Sterile Normal Saline ◽

Animal Skin ◽

The Impact

Background. This study examines the impact of one-time direct application of haemostatic agent zeolite–bentonite powder to wounded skin on the healing process in rats. Materials and Methods. 24 male Sprague-Dawley rats were randomly allocated into two groups (n=12): (1) the rats whose wounds were washed only with sterile normal saline (NS-treated) and (2) those treated with zeolite–bentonite compound (ZEO-treated). The wound was circular, full-thickness, and 2 cm in diameter. At the end of the 12th day, six animals from each group were randomly selected and terminated. The remaining rats were terminated after 21 days. Just after scarification, skin samples were excised and sent for stereological evaluation. Results. The results showed a significant difference between the two groups regarding the length density of the blood vessels and diameter of the large and small vessels on the 12th day after the wound was inflicted. Besides, volume density of both the dermis and collagen bundles was reduced by 25% in the ZEO-treated rats in comparison to the NS-treated animals after 21 days. Conclusions. One-time topical usage of zeolite–bentonite haemostatic powder on an animal skin wound might negatively affect the healing process through vasoconstriction and inhibition of neoangiogenesis.

Download Full-text

Norepinephrine-evoked salt-sensitive hypertension requires impaired renal sodium chloride cotransporter activity in Sprague-Dawley rats

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00514.2014 ◽

2016 ◽

Vol 310 (2) ◽

pp. R115-R124 ◽

Cited By ~ 12

Author(s):

Kathryn R. Walsh ◽

Jill T. Kuwabara ◽

Joon W. Shim ◽

Richard D. Wainford

Keyword(s):

Blood Pressure ◽

Sodium Chloride ◽

Salt Sensitivity ◽

Dietary Sodium ◽

Ang Ii ◽

Sprague Dawley ◽

Sodium Chloride Cotransporter ◽

Sprague Dawley Rats ◽

Salt Sensitive Hypertension ◽

The Impact

Recent studies have implicated a role of norepinephrine (NE) in the activation of the sodium chloride cotransporter (NCC) to drive the development of salt-sensitive hypertension. However, the interaction between NE and increased salt intake on blood pressure remains to be fully elucidated. This study examined the impact of a continuous NE infusion on sodium homeostasis and blood pressure in conscious Sprague-Dawley rats challenged with a normal (NS; 0.6% NaCl) or high-salt (HS; 8% NaCl) diet for 14 days. Naïve and saline-infused Sprague-Dawley rats remained normotensive when placed on HS and exhibited dietary sodium-evoked suppression of peak natriuresis to hydrochlorothiazide. NE infusion resulted in the development of hypertension, which was exacerbated by HS, demonstrating the development of the salt sensitivity of blood pressure [MAP (mmHg) NE+NS: 151 ± 3 vs. NE+HS: 172 ± 4; P < 0.05]. In these salt-sensitive animals, increased NE prevented dietary sodium-evoked suppression of peak natriuresis to hydrochlorothiazide, suggesting impaired NCC activity contributes to the development of salt sensitivity [peak natriuresis to hydrochlorothiazide (μeq/min) Naïve+NS: 9.4 ± 0.2 vs. Naïve+HS: 7 ± 0.1; P < 0.05; NE+NS: 11.1 ± 1.1; NE+HS: 10.8 ± 0.4). NE infusion did not alter NCC expression in animals maintained on NS; however, dietary sodium-evoked suppression of NCC expression was prevented in animals challenged with NE. Chronic NCC antagonism abolished the salt-sensitive component of NE-mediated hypertension, while chronic ANG II type 1 receptor antagonism significantly attenuated NE-evoked hypertension without restoring NCC function. These data demonstrate that increased levels of NE prevent dietary sodium-evoked suppression of the NCC, via an ANG II-independent mechanism, to stimulate the development of salt-sensitive hypertension.

Download Full-text

The Impact of DJOS Surgery, a High Fat Diet and a Control Diet on the Enzymes of Glucose Metabolism in the Liver and Muscles of Sprague-Dawley Rats

Frontiers in Physiology ◽

10.3389/fphys.2019.00571 ◽

2019 ◽

Vol 10 ◽

Cited By ~ 1

Author(s):

Dominika Stygar ◽

Dorian Andrare ◽

Barbara Bażanów ◽

Elżbieta Chełmecka ◽

Tomasz Sawczyn ◽

...

Keyword(s):

Glucose Metabolism ◽

High Fat Diet ◽

Control Diet ◽

Sprague Dawley ◽

High Fat ◽

Sprague Dawley Rats ◽

The Impact

Download Full-text

Developmental Profiles of Neuroendocrine Gene Expression in the Preoptic Area of Male Rats

Endocrinology ◽

10.1210/en.2008-1396 ◽

2009 ◽

Vol 150 (5) ◽

pp. 2308-2316 ◽

Cited By ~ 34

Author(s):

Deena M. Walker ◽

Thomas E. Juenger ◽

Andrea C. Gore

Keyword(s):

Molecular Mechanisms ◽

Preoptic Area ◽

Reproductive Function ◽

Gonadal Hormones ◽

Male Rats ◽

Low Density ◽

Sprague Dawley ◽

Serum Hormones ◽

Sprague Dawley Rats ◽

Steroid Sensitive

Reproductive function is controlled by GnRH cells and their steroid-sensitive regulatory inputs. The proper maturation of this system is critical to sexual development and maintenance of adult function. However, the molecular mechanisms underlying these developmental changes, and the potential roles of gonadal hormones in sculpting these processes, have not been fully explored. We performed a developmental profile from postnatal day (P) 1 through P60 of a network of five genes in the preoptic area (POA) that are critical to reproduction in male Sprague Dawley rats. GnRH, estrogen receptors-α, and -β, androgen receptor (AR), and progesterone receptor (PR) mRNAs in the POA were assayed, and serum hormones were measured, in developing male rats. We also used a Taqman low-density array to identify candidate genes that may be important in development. Of the five targeted genes, only AR and PR changed robustly (7- and 3- to 4-fold increases, respectively) during development. All of the gonadal serum hormones changed markedly and with very different patterns from their receptor mRNAs: testosterone decreased from P1 to P30 and then increased to P60; progesterone peaked on P30; and estradiol decreased from P1 to P30. Using the Taqman low-density array, we identified several genes that changed dramatically in the POA with development, particularly G protein-coupled receptor 30, IGF-I, vitamin D receptor, estrogen-related receptor-α, and thyroid receptor-α. Our data demonstrate developmental stage-specific changes in neuroendocrine genes, particularly AR and PR. Moreover, the relationships between hormones and their corresponding receptors undergo dynamic changes across development in male rats.

Download Full-text

Effects of Diet-Induced Obesity and Deficient in Vitamin D on Spermatozoa Function and DNA Integrity in Sprague-Dawley Rats

BioMed Research International ◽

10.1155/2018/5479057 ◽

2018 ◽

Vol 2018 ◽

pp. 1-6 ◽

Cited By ~ 5

Author(s):

O. Merino ◽

R. Sánchez ◽

B. M. Gregorio ◽

F. J. Sampaio ◽

J. Risopatrón

Keyword(s):

Vitamin D ◽

Dna Fragmentation ◽

High Fat Diet ◽

Control Diet ◽

Sperm Function ◽

Sprague Dawley ◽

High Fat ◽

Diet Induced Obesity ◽

Sprague Dawley Rats ◽

The Impact

Obesity has adverse effects on male fertility and usually is diagnosed with a prevalence of vitamin D deficiency (VD-). Discussion on the impact of obesity/VD- on sperm function has been limited. This study analyzed the effects of diet-induced obesity/VD- on viability and plasma membrane integrity (PMI), superoxide anion (O2-) level, and DNA fragmentation (DNAfrag) in sperm Sprague-Dawley rats. The males were randomized into four groups and fed for a period of 12 weeks: G1: control diet with vitamin D (C/VD+), G2: control diet without vitamin D (C/VD-), G3: high-fat diet with vitamin D (HF/VD+), and G4: high-fat diet without vitamin D (HF/VD-). Sperm function parameters were analyzed by flow cytometry. PMI percentages and O2- levels were not affected by any of the diets. DNA fragmentation was increasing significantly (p<0.05) in the spermatozoa of animals with diets vitamin D deficient (G2) and diet-induced obesity (G4). Our results allow us to point out that diet-induced obesity and VD- produce greater damage in DNA sperm of rats. The use of nutraceuticals containing vitamin D could be reducing the risk of fragmentation of DNA in spermatozoa.

Download Full-text