Electrophysiological and biochemical response in rats on intratracheal instillation of manganese

2011 ◽  
Vol 6 (6) ◽  
pp. 925-932
Author(s):  
Zsuzsanna Máté ◽  
Andrea Szabó ◽  
Edit Paulik ◽  
Zsanett Jancsó ◽  
Edit Hermesz ◽  
...  
Keyword(s):  
Body Weight Gain ◽  
Relative Weight ◽  
Intratracheal Instillation ◽  
Double Pulse ◽  
Central Nervous System Damage ◽  
Cortical Responses ◽  
Blood Relative ◽  
Male Wistar Rats ◽  
Urethane Anaesthesia ◽  
Pulse Stimulation

AbstractChronic exposure to excess manganese via inhalation of metal fumes causes central nervous system damage. For modelling Mn aerosol inhalation, male Wistar rats were intratracheally instilled with MnCl2 solution (0.5 mg/kg b.w. MnCl2; n=12) 5 days a week for 5 weeks. At the end of the treatment, somatosensory cortical evoked potentials, elicited by double-pulse stimulation, were recorded from the animals in urethane anaesthesia. Body weight gain, organ weights, and Mn level in brain, lung and blood samples were also measured. In brain samples, gene expression level of MnSOD (Mn superoxide dismutase) was determined. The effect of Mn was mainly seen on the evoked potential amplitudes, and on the second:first ratio of these. Tissue Mn concentration was elevated in brain and lungs, but changed hardly in the blood. Relative weight of heart, thymus, lungs and brain was significantly altered. The level of MnSOD transcript in brain tissue decreased. The observed effects showed that Mn had access to the brain and that somatosensory cortical responses evoked by double-pulse stimulation might be suitable biomarkers of Mn intoxication.

scholarly journals A Blunted Sympathetic Function and an Enhanced Nitrergic Activity Contribute to Reduce Mesenteric Resistance in Hyperthyroidism

2021 ◽  
Vol 22 (2) ◽  
pp. 570
Author(s):  
Laia Cros-Brunsó ◽  
Laura Camacho-Rodríguez ◽  
Ángel Martínez-González ◽  
Pablo Llévenes ◽  
Mercedes Salaices ◽  
...  
Keyword(s):  
Citrate Synthase ◽  
Purinergic Receptor ◽  
Body Weight Gain ◽  
Electrical Field Stimulation ◽  
Alpha Adrenoceptor ◽  
Adrenoceptor Antagonist ◽  
Sympathetic Function ◽  
Vasoconstrictor Response ◽  
Relevant Role ◽  
Male Wistar Rats

We aimed to determine whether an experimental model of hyperthyroidism could alter the function of sympathetic and nitrergic components of mesenteric innervation. For this purpose, male Wistar rats were divided into (1) control rats (CT) and (2) rats infused with L-Thyroxine (HT). Body weight gain and adipose tissue accumulation were lower in HT rats, while systolic blood pressure and citrate synthase activity in the soleus muscle were increased by HT. In segments from the superior mesenteric artery, the application of an electrical field stimulation (EFS) induced a vasoconstrictor response, which was lower in arteries from HT animals. The alpha-adrenoceptor antagonist phentolamine diminished EFS-induced vasoconstriction to a lower extent in HT arteries, while the purinergic receptor antagonist suramin reduced contractile response to EFS only in segments from CT. In line with this, noradrenaline release, tyrosine hydroxylase expression and activation and dopamine β hydroxylase expression were diminished in HT. The unspecific nitric oxide synthase (NOS) inhibitor L-NAME increased EFS-induced vasoconstriction more markedly in segments from HT rats. NO release was enhanced in HT, probably due to an enhancement in neuronal NOS activity, in which a hyperactivation of both PKC and PI3K-AKT signaling pathways might play a relevant role. In conclusion, perivascular mesenteric innervation might contribute to reduce the vascular resistance observed in hyperthyroidism.

scholarly journals Subchronic Toxicity Study in Rats of Two New Ethyl-Carbamates with Ixodicidal Activity

2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
María Guadalupe Prado-Ochoa ◽  
Víctor Hugo Abrego-Reyes ◽  
Ana María Velázquez-Sánchez ◽  
Marco Antonio Muñoz-Guzmán ◽  
Patricia Ramírez-Noguera ◽  
...  
Keyword(s):  
Plasma Proteins ◽  
Clinical Signs ◽  
Relative Weight ◽  
Thiobarbituric Acid ◽  
Male Rats ◽  
Gamma Glutamyl Transpeptidase ◽  
Subchronic Toxicity ◽  
Biochemical Alterations ◽  
Male Wistar Rats ◽  
Glutamyl Transpeptidase

Female and male Wistar rats were used to determine the subchronic oral toxicities of two new ethyl-carbamates with ixodicidal activities (ethyl-4-bromphenyl-carbamate and ethyl-4-chlorphenyl-carbamate). The evaluated carbamates were administered in the drinking water (12.5, 25 and 50 mg/kg/day) for 90 days. Exposure to the evaluated carbamates did not cause mortality or clinical signs and did not affect food consumption or weight gain. However, exposure to these carbamates produced alterations in water consumption, hematocrit, percentages of reticulocytes, plasma proteins, some biochemical parameters (aspartate aminotransferase, gamma-glutamyl transpeptidase, cholinesterase, and creatinine activities), thiobarbituric acid reactive substances, and the relative weight of the spleen. Histologically, slight pathological alterations were found in the liver that were consistent with the observed biochemical alterations. The nonobserved adverse effect levels (NOAELs) of the evaluated carbamates were 12.5 mg/kg/day for both the female and male rats. The low severity and reversibility of the majority of the observed alterations suggest that the evaluated carbamates have low subchronic toxicity.

Practical Application of Microcapsulation for Toxicity Studies Using Bromodichloromethane as a Model Compound

1989 ◽  
Vol 8 (6) ◽  
pp. 1177-1187
Author(s):  
Y. Aida ◽  
M. Ando ◽  
K. Takada ◽  
J Momma ◽  
H. Yoshimoto ◽  
...  
Keyword(s):  
Body Weight ◽  
Olive Oil ◽  
Body Weight Gain ◽  
Male Rats ◽  
Toxicity Tests ◽  
Bile Duct Proliferation ◽  
Volatile Chemicals ◽  
Feeding Study ◽  
Toxicity Studies ◽  
Male Wistar Rats

Gelatin-starch syrup (food grade) microcapsulation was applied for toxicology studies of bromodichloromethane (BDCM). BDCM concentrations were stable for 120 days in the microcapsules and for 9 months when incorporated in the powder diet. BDCM concentration in the blood following the administration of microcapsules in olive oil suspension was retained at higher levels than when BDCM was administered as olive oil solution. Subsequently, the microcapsules were mixed in powder diet and were given at concentrations of microcapsulated BDCM of 0, 0.024, 0.072, and 0.215% to groups of 7 male Wistar rats for 1 month. For comparison, BDCM dissolved in olive oil was administered by gavage to groups of 7 male rats for 1 month at dosage levels adjusted to those in the feeding study (0, 20, 60, and 180 mg/kg body weight). Suppression of body weight gain was seen in the high-dosage groups in both the feeding and the gavage studies and was more severe in the former. Similar histopathologic lesions in the liver were shown in both studies, including vacuolization, swelling, and single necrosis of liver cells. Hepatic cord irregularity and bile duct proliferation were observed in the feeding study but not the gavage study. Serum biochemical changes, such as decreases in glucose, triglyceride, and cholinesterase levels, which reflected the histopathologic findings in the liver, were also observed in both studies. Accordingly, the microcapsulation process was proved to pose no qualitative toxic effects on toxicity of BDCM in short-term toxicity studies. It is concluded that the application of microcapsulation is useful for toxicity tests of volatile chemicals when incorporated into food.

scholarly journals Nicotinamide Riboside Neutralizes Hypothalamic Inflammation and Increases Weight Loss Without Altering Muscle Mass in Obese Rats Under Calorie Restriction: A Preliminary Investigation

2021 ◽  
Vol 8 ◽  
Author(s):  
Josimar Macedo de Castro ◽  
Dirson João Stein ◽  
Helouise Richardt Medeiros ◽  
Carla de Oliveira ◽  
Iraci L. S. Torres
Keyword(s):  
Weight Loss ◽  
Muscle Mass ◽  
Calorie Restriction ◽  
Preliminary Investigation ◽  
Relative Weight ◽  
Nicotinamide Riboside ◽  
Tnf Α ◽  
Obese Rats ◽  
Male Wistar Rats ◽  
Hypothalamic Inflammation

Obesity treatments, such as calorie restriction (CR), eventually lead to muscle wasting and higher rates of neuroinflammation, whereas hypothalamic inflammatory conditions impair body weight (BW) control. Nicotinamide riboside (NR) has been proposed against obesity but with little evidence on skeletal muscle tissue (SMT) and neuroinflammation. Therefore, we aimed to investigate the effects of CR on SMT and on hypothalamic inflammatory biomarkers in obese adult male Wistar rats, and whether NR supplementation alone or in combination with CR affects these parameters. Obesity was induced in rats through a cafeteria diet for 6 weeks. After that, a group of obese rats was exposed to CR, associated or not associated with NR supplementation (400 mg/kg), for another 4 weeks. As a result, obese rats, with or without CR, presented lower relative weight of SMT when compared with eutrophic rats. Rats under CR presented lower absolute SMT weight compared with obese and eutrophic rats, in addition to presenting elevated hypothalamic levels of TNF-α. NR supplementation, in all groups, enhanced weight loss and increased relative weight of the SMT. Furthermore, in animals under CR, NR reversed increases TNF-α levels in the hypothalamus. In this study, these data, although succinct, are the first to evidence the effects of NR on SMT and neuroinflammation when associated with CR, especially in obesity conditions. Therefore, this provides preliminary support for future studies in this investigative field. Furthermore, NR emerges as a potential adjuvant for preventing muscle mass loss in the weight loss processes.

scholarly journals Evaluation of the supplementation of a feed additive as a potential protector against the adverse effects of 2.5 ppm T-2 toxin on growing broiler chickens

2016 ◽  
Vol 68 (3) ◽  
pp. 709-715 ◽  
Author(s):  
G.J. Diaz ◽  
M.L. Vargas ◽  
A. Cortés
Keyword(s):  
Adverse Effects ◽  
Broiler Chickens ◽  
Digestive System ◽  
Body Weight Gain ◽  
Relative Weight ◽  
Experimental Treatment ◽  
Additive Group ◽  
Negative Control ◽  
Feed Additive ◽  
Feed Conversion

ABSTRACT A trial was conducted to evaluate a feed additive containing epoxidase activity from a bacterium (Mycofix-S) as a potential protection against the adverse effects of 2.5 ppm dietary T-2 toxin in male growing broiler chickens. A total of 144 one-day-old Ross 308 male chicks were individually wing-banded and allotted into each of the four experimental groups. Group 1: negative control, no T-2 toxin or additive; group 2: Mycofix-S, 2.5 g/kg; group 3: positive control, 2.5 ppm T-2 toxin; group 4: 2.5 ppm T-2 toxin + 2.5 g/kg Mycofix-S. Feed and water were provided ad libitum for 28 days (days 1 to 28 of age). Each experimental treatment was replicated 6 times, with 6 birds per replicate pen. Response variables included performance parameters, serum activity of alkaline phosphatase (ALP) and amylase, relative weight of selected organs and histology of the upper digestive system. T-2 toxin at 2.5 ppm significantly (P = 0.016) decreased the 28-day body weight gain and cumulative feed intake without affecting feed conversion. The feed additive counteracted these adverse effects. Serum enzyme activities were not significantly (P>0.05) affected for the four experimental groups but when data from the groups receiving T-2 toxin was pooled and compared against the pooled data from groups without the toxin a significant decrease in amylase activity was observed in chickens receiving T-2 toxin. The histological examination of the upper digestive system revealed lesions in mouth, esophagus, proventriculus, gizzard and duodenum in the chickens fed T-2 toxin without the additive. Chickens fed T-2 toxin plus the additive showed lesions in the same tissues except in the duodenum. The results of the present study show that the addition of 2.5 g/kg of the feed additive tested protects against adverse effects on performance and also the integrity of the duodenal mucosa.

EFFECT OF ERGOT FROM DIFFERENT SOURCES AND OF FRACTIONATED ERGOT ON THE PERFORMANCE OF GROWING CHICKS

1985 ◽  
Vol 65 (4) ◽  
pp. 953-961 ◽  
Author(s):  
R. G. ROTTER ◽  
R. R. MARQUARDT ◽  
J. C. YOUNG
Keyword(s):  
Body Weight Gain ◽  
Relative Weight ◽  
Ergot Alkaloids ◽  
Feed Consumption ◽  
Toxic Activity ◽  
Toxic Component ◽  
Total Alkaloids ◽  
Alkaloid Fraction ◽  
Total Alkaloid Content ◽  
Different Sources

A series of experiments was conducted on growing chicks to compare the toxic effects of ergot from different sources and to partially fractionate the toxic component(s) in ergot. Changes in body weight gain, feed consumption relative to control birds and mortality were used as indicators of toxicity. Seven-day-old male Leghorn chicks were offered feed containing ground ergot from rye, wheat and triticale for a period of 7 days. The ergot samples were obtained from different locations in Canada and were added to the diets so that the concentration of total alkaloids was either 45 or 90 mg/kg. The relative weight gains for birds fed diets containing 45 and 90 mg/kg total alkaloids varied considerably, ranging from 49 to 65% and from 18 to 42% of controls, respectively. The degree of depression in relative performance was not uniform among the different ergot samples when their concentration in the diet was increased. In a fractionation study, most of the toxic activity in the ergot was concentrated in the alkaloid fraction, suggesting that most of the toxic components are alkaloid related. There was also some loss of the alkaloids and the corresponding potency of toxic factors during the isolation. It may be concluded that the total alkaloid content of an ergot sample can be used to predict the effects of ergot on chick performance. However, it is not a highly accurate prediction due to the variable content and variable effects of the individual alkaloids in a given sample and because most of the toxic activity of ergot is associated with the alkaloid fraction. Key words: Ergot, alkaloids, chick performance, toxic component(s)

Effect of microbial proteases on the performance and carcass traits in commercial broilers fed maize-soy bean meal -meat cum bone meal based diets

2018 ◽  
Author(s):  
T. Srilatha ◽  
V. Ravinder Reddy ◽  
V. Chinni Preetam ◽  
S. V. Rama Rao ◽  
Y. Ramana Reddy
Keyword(s):  
Body Weight ◽  
Weight Gain ◽  
Soybean Meal ◽  
Body Weight Gain ◽  
Carcass Traits ◽  
Relative Weight ◽  
The Body ◽  
Alkaline Proteases ◽  
Bone Meal ◽  
Low Protein

An experiment was conducted to evaluate the effective combinations of proteases (acid, neutral and alkaline) and their concentrations on performance and carcass traits in commercial broilers fed on diets containing sub-optimal protein levels. A total of 320 broilers were used in completely randomized design with eight treatments with eight replicates in each treatment and 5chicks in each replicate. Maize-soybean meal (CD) and maize-soybean-meat cum bone meal (BD) based diets were formulated to contain 23, 21 and 19.5% crude protein (CP) and 19.5,18 and 17.5% CP, respectively during pre-starter (1-11 d), starter (12-28d) and finisher (29-42d) phases. All the diets were fed adlibitum from 1d to 42 d of age. The low protein BD were supplemented with two different combinations of proteases (1:1:1 and 2:1:1 acidic, neutral and alkaline proteases, respectively) with total activity of 2000, 4000 and 6000u/kg.The results revealed that the broilers fed CD had significantly higher body weight gain compared to those fed BD. Supplementation of proteases to the BD significantly (P LESS THAN 0.05) improved the body weight gain and feed efficiency during 21 d of age, but not during the latter phase ( 42 d of age) of growth. The broilers fed on CD had significantly (P less than 0.05) higher ready to cook and breast yields compared to those fed the BD or BD with protease supplementation. The relative weight of abdominal fat was significantly (P less than 0.05) reduced in broilers fed BD with 1:1:1 (acidic, neutral and alkaline proteases) at 4000 u protease / kg diet as compared to BD. It is suggested that addition of proteases to low protein diets had a significant positive effect in young chicken fed on maize-soybean meal and -meat and bone meal based diets.

Knocking down the diencephalic thyrotropin-releasing hormone precursor gene normalizes obesity-induced hypertension in the rat

2007 ◽  
Vol 292 (5) ◽  
pp. E1388-E1394 ◽  
Author(s):  
María S. Landa ◽  
Silvia I. García ◽  
Mariano L. Schuman ◽  
Adriana Burgueño ◽  
Azucena L. Alvarez ◽  
...  
Keyword(s):  
Body Weight ◽  
Body Weight Gain ◽  
Strong Association ◽  
Green Fluorescence Protein ◽  
Antisense Oligodeoxynucleotide ◽  
Arterial Blood ◽  
Induced Hypertension ◽  
Male Wistar Rats ◽  
Antisense Sequence ◽  
Systolic Arterial Blood Pressure

We recently showed that diencephalic TRH may mediate the central leptin-induced pressor effect. Here, to study the role of TRH in obesity-induced hypertension (OIH), we used a model of OIH produced by a high-fat diet (HFD, 45 days) in male Wistar rats. After 4 wk, body weight and systolic arterial blood pressure (SABP) increased in HFD animals. Plasma leptin was correlated with peritoneal adipose tissue. Then, we treated OIH animals with an antisense oligodeoxynucleotide and small interfering (si)RNA against the prepro-TRH. Antisense significantly decreased diencephalic TRH content and SABP at 24 and 48 h posttreatment. Similar effects were observed with siRNA against prepro-TRH but for up to 4 wk. Conversely, vehicle, an inverted antisense sequence and siRNA against green fluorescence protein, produced no changes. SABP decrease seems to be owing to an inhibition of the obesity-enhanced sympathetic outflow but not to an alteration in thyroid status. Using a simple OIH model we demonstrated, for the first time, that central TRH participates in the hypertension induced by body weight gain probably through its well-known action on sympathetic activity. Thus the TRH-leptin interaction may contribute to the strong association between hypertension and obesity.

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