Centrally administered MTII affects feeding, drinking, temperature, and activity in the Sprague-Dawley rat

2000 ◽  
Vol 89 (1) ◽  
pp. 273-282 ◽  
Author(s):  
B. Murphy ◽  
C. N. Nunes ◽  
J. J. Ronan ◽  
M. Hanaway ◽  
A. M. Fairhurst ◽  
...  
Keyword(s):  
Third Ventricle ◽  
Dose Range ◽  
Behavioral Changes ◽  
Dependent Manner ◽  
Low Doses ◽  
Drinking Patterns ◽  
Sprague Dawley ◽  
Nocturnal Feeding ◽  
Dose Dependent ◽  
Higher Doses

MTII, an agonist of melanocortinergic receptors, is a well-documented anorexigenic agent in rats. Many investigators have reported its effects on feeding without considering concurrent alterations in other behaviors. Accordingly, we performed studies to simultaneously measure nocturnal feeding, drinking, activity, and temperature of rats after intracerebroventricular (third ventricle) administration of a wide dose range of MTII (0.05–500 ng). We observed that MTII modulates these physiological parameters in a dose-dependent manner. Low doses of MTII (0.05 ng) caused reductions in feeding without alterations in body temperature, drinking, or activity. In contrast, hyperthermia and disrupted drinking patterns, along with food intake reductions, were evident at doses exceeding 50 ng. The fact that low doses altered only feeding, whereas higher doses affected a range of parameters, suggests that certain melanocortin-induced behavioral changes may be mediated by distinct populations of melanocortin receptors with varying affinities or that those changes seen at higher doses may be nonspecific in nature.

Interaction of propranolol and phentolamine with ethanol in the rat

1976 ◽  
Vol 54 (4) ◽  
pp. 622-625 ◽  
Author(s):  
D. Frankel ◽  
H. Kalant ◽  
J. M. Khanna ◽  
A. E. LeBlanc
Keyword(s):  
Nervous System ◽  
Dependent Manner ◽  
Low Doses ◽  
Adrenergic Mechanism ◽  
Adrenergic Nervous System ◽  
Ethanol Effect ◽  
Dose Dependent ◽  
Higher Doses

The possible role of the adrenergic nervous system in the intoxicant effects of ethanol was examined in studies of the interaction of propranolol and phentolamine with ethanol. Propranolol tended to increase the effect of lower doses of ethanol in a dose-dependent manner. However, the effect of higher doses of ethanol (over 2.0 g/kg) tended to be diminished by low doses of propranolol, whereas higher doses of propranolol were ineffective or actually increased the ethanol effect. Phentolamine tended to decrease the effect of the lower ethanol doses. These findings are inconsistent with any simple adrenergic mechanism in the mediation of the intoxicant effect of ethanol.

Involvement of 5-Hydroxytryptamine in Platelet Aggregation In Vivo in Rats and Guinea Pigs

1989 ◽  
Vol 61 (03) ◽  
pp. 463-467 ◽  
Author(s):  
G M Smith
Keyword(s):  
Platelet Count ◽  
Guinea Pigs ◽  
Platelet Adhesion ◽  
Adenosine Diphosphate ◽  
Rate Of Return ◽  
Low Doses ◽  
Dose Dependent ◽  
Higher Doses ◽  
Rat Platelets

SummaryIn this study, 5-hydroxytryptamine (5-HT) caused a dose- dependent fall in the circulating platelet count suggesting that 5-HT receptors are activated in rat platelets to cause platelet adhesion and aggregation. When low doses of adenosine diphosphate (ADP) were simultaneously injected with 5-HT, there was a significant potentiation of the responses to ADR Ketanserin significantly reduced the potentiated responses. When higher doses of ADP were infused with bolus injections of 5-HT there was no potentiation and ketanserin did not reduce these responses. Ketanserin did not inhibit the collagen-induced fall in circulating platelet count, but did significantly increase the rate of return to the basal platelet count compared with control. 5-HT did not cause a fall in platelet count in guinea-pigs

scholarly journals In Utero Exposure to Di(n)butyl Phthalate Reduces Testicular Testosterone and Testes Size in a Dose-Dependent Manner in Harlan Sprague Dawley Fetal Rats.

2009 ◽  
Vol 81 (Suppl_1) ◽  
pp. 636-636
Author(s):  
Kembra L. Howdeshell ◽  
Johnathan Furr ◽  
Christy R. Lambright ◽  
Vickie Wilson ◽  
L. Earl Gray
Keyword(s):  
In Utero ◽  
In Utero Exposure ◽  
Dependent Manner ◽  
Sprague Dawley ◽  
Fetal Rats ◽  
Testes Size ◽  
Butyl Phthalate ◽  
Dose Dependent

Glutamine promotes triglyceride absorption in a dose-dependent manner

2002 ◽  
Vol 282 (2) ◽  
pp. G317-G323 ◽  
Author(s):  
Jeffrey B. Schwimmer ◽  
Looi Ee ◽  
Shuqin Zheng ◽  
Patrick Tso
Keyword(s):  
Amino Acid ◽  
Amino Acid Mixture ◽  
Lipid Absorption ◽  
Acid Mixture ◽  
Dependent Manner ◽  
Sprague Dawley ◽  
Feeding Tubes ◽  
Mesenteric Lymph ◽  
Sprague Dawley Rats ◽  
Dose Dependent

Dietary proteins may play a role in lipid absorption. Whether amino acids are specifically involved is unknown. We hypothesized that enterally administered l-glutamine (l-Gln) given with a lipid meal increases triglyceride (TG) absorption in rats. Mesenteric lymph fistulae and gastroduodenal feeding tubes were placed in adult male Sprague-Dawley rats. The animals received an enteral bolus of Intralipid (5 ml) followed by enteral infusion of increasing concentrations of l-Gln in saline (0, 85, 170, or 340 mM) or equimolar concentrations of the inactive isomer d-Gln or an essential amino acid mixture without Gln. Lymph was collected continuously for 6 h and analyzed for TG content. Animals infused with 85 mM l-Gln had a 64% increase in total TG output vs. controls ( P < 0.05) despite no difference in lymph flow rate. Total TG output for animals infused with 340 mMl-Gln declined by 43% vs. controls ( P < 0.05). The effect of Gln in promoting lymphatic fat transport is specific to l-Gln and not shared by d-Gln or an equivalent amino acid mixture. l-Gln is capable of either promoting or impairing lymphatic TG transport in a dose-dependent manner.

Cinnamomum cassia ameliorates Ni-NPs-induced liver and kidney damage in male Sprague Dawley rats

2020 ◽  
Vol 39 (11) ◽  
pp. 1565-1581
Author(s):  
S Iqbal ◽  
F Jabeen ◽  
C Peng ◽  
MU Ijaz ◽  
AS Chaudhry
Keyword(s):  
Dependent Manner ◽  
Sprague Dawley ◽  
Cinnamomum Cassia ◽  
Preliminary Information ◽  
Sprague Dawley Rats ◽  
Liver And Kidney ◽  
Altered Blood ◽  
Biochemical Analyses ◽  
Dose Dependent ◽  
Different Doses

Nickel nanoparticles (Ni-NPs) have been widely used in various industries related to electronics, ceramics, textiles, and nanomedicine. Ambient and occupational exposure to Ni-NPs may bring about potential detrimental effects on animals and humans. Thus, there is a growing effort to identify compounds that can ameliorate NPs-associated pathophysiologies. The present study examined Cinnamomum cassia ( C. cassia) bark extracts (CMBE) for its ameliorative activity against Ni-NPs-induced pathophysiological and histopathological alterations in male Sprague Dawley rats. The biochemical analyses revealed that dosing rats with Ni-NPs at 10 mg/kg/body weight (b.w.) significantly altered the normal structural and biochemical adaptations in the liver and kidney. Conversely, supplementations with CMBE at different doses (225, 200, and 175 mg/kg/b.w. of rat) ameliorated the altered blood biochemistry and reduced the biomarkers of liver and kidney function considerably ( p < 0.05) in a dose-dependent manner. However, the best results were at 225 mg/kg/b.w. of rat. The study provided preliminary information about the protective effect of C. cassia against Ni-NPs indicated liver and kidney damages. Future investigations are needed to explore C. cassia mechanism of action and isolation of single constituents of C. cassia to assess their pharmaceutical importance accordingly.

scholarly journals Collagen-Induced Reduction in Rat Circulating Platelet Count: Influence of Platelet Function Inhibitors

1977 ◽  
Author(s):  
I.B. Holmes
Keyword(s):  
Platelet Count ◽  
Platelet Function ◽  
Test System ◽  
Collagen Fibrils ◽  
Dependent Manner ◽  
Sprague Dawley ◽  
Sprague Dawley Rats ◽  
Dose Dependent ◽  
Double Lumen Cannula ◽  
Antiinflammatory Compound

The effect on circulating platelet count of repeated intravenous infusions of collagen fibrils was measured in male OFA Sprague-Dawley rats (400-550 g). Citrated blood was pumped from the left carotid artery of anaesthetized animals, via a siliconized double-lumen cannula, into the manifold of a Technicon Autocounter, for continuous registration of platelet count. Native collagen fibrils (Collagenreagent ‘Horm’) were infused intravenously for 1 min at 15 min intervals. Successive increasing collagen doses (20-320 pg/kg) induced dose-dependent reduction in platelet count, measured as absolute platelet number disappearing from the circulation. Repeated infusion of collagen 160 pg/kg produced constant, partially reversible, reduction in platelet count. Several known inhibitors of platelet aggregation were investigated in the described test system. Collagen effects were inhibited in a dose-dependent manner to a maximum of 50-60 %, and drug activity was thus quantitated on the basis of dose producing 30 % inhibition (ID30): prostaglandin E1 (1.6 pg/kg/min i.v. infusion), SH-869 (1.1 mg/kg i.v.), aspirin (33.1 mg/kg p.o.), proquazone, a new non-steroidal antiinflammatory compound (5.0 mg/kg p.o.). That part of the collagen response not inhibited might be attributed to the initial phase of platelet adhesion to collagen, known to be relatively refractive to platelet function inhibitors.

scholarly journals The osteoprotective effect ofHerba epimedii(HEP) extractin vivoandin vitro

2005 ◽  
Vol 2 (3) ◽  
pp. 353-361 ◽  
Author(s):  
Fang Xie ◽  
Chun-Fu Wu ◽  
Wan-Ping Lai ◽  
Xu-juan Yang ◽  
Pik-Yuan Cheung ◽  
...  
Keyword(s):  
Serum Alkaline Phosphatase ◽  
Calcium Excretion ◽  
Dependent Manner ◽  
Sprague Dawley ◽  
Alp Activity ◽  
Post Menopausal Osteoporosis ◽  
Ovx Rats ◽  
Rankl Mrna ◽  
Umr 106 ◽  
Dose Dependent

Herba epimedii(HEP) is one of the most frequently used herbs prescribed for treatment of osteoporosis in China. In the present study, thein vivoeffects of HEP extract on bone metabolism were evaluated using 4-month-old ovariectomized (OVX) or sham-operated (Sham) female Sprague-Dawley rats orally administered with HEP extract (110 mg kg−1d−1), 17ß-estrogen (2 mg kg−1d−1) or its vehicle for 3 months. HEP extract significantly decreased urinary calcium excretion, suppressed serum alkaline phosphatase (ALP) activity and urinary deoxypyridinoline levels in OVX rats (P< 0.05 versus vehicle-treated OVX rats). Histomorphometric analysis indicated that HEP extract could prevent OVX-induced bone loss by increasing tibial trabecular bone area and decreasing trabecular separation in OVX rats (P< 0.05 versus vehicle-treated OVX group). Thein vitroeffects of HEP extract were also studied using rat osteoblast-like UMR 106 cells. HEP extract significantly stimulated cell proliferation in a dose-dependent manner (P< 0.01 versus vehicle-treated) and increased ALP activity at 200 μgml−1 (P< 0.01 versus vehicle-treated) in UMR 106 cells. It modulated osteoclastogenesis by increasing osteoprotegrin (OPG) mRNA and decreasing receptor activator of NF-κB ligand (RANKL) mRNA expression, resulting in a dose-dependent increase in OPG/RANKL mRNA ratio (P< 0.01 versus vehicle-treated). Taken together, HEP treatment can effectively suppress the OVX-induced increase in bone turnover possibly by both an increase in osteoblastic activities and a decrease in osteoclastogenesis. The present study provides the evidence that HEP can be considered as a complementary and alternative medicine for treatment of post-menopausal osteoporosis.

Protective Effect of Reduced Glutathione against CIS-Dichlorodiammine Platinum (II)–Induced Nephrotoxicity and Lethal Toxicity

1983 ◽  
Vol 69 (2) ◽  
pp. 105-111 ◽  
Author(s):  
Franco Zunino ◽  
Odoardo Tofanetti ◽  
Adriana Besati ◽  
Ennio Cavalletti ◽  
Giuseppina Savi
Keyword(s):  
Reduced Glutathione ◽  
Body Weight Loss ◽  
Dependent Manner ◽  
Sprague Dawley ◽  
Antitumor Effects ◽  
Partial Protection ◽  
Lethal Toxicity ◽  
Sprague Dawley Rats ◽  
Serum Blood Urea Nitrogen ◽  
Dose Dependent

Pretreatment of Swiss mice and Sprague-Dawley rats with glutathione (GSH) reduced the acute lethal toxicity of cis-dichlorodiammine platinum (II) (cis-DDP) in a dose-dependent manner. The protection was accompanied by reduction of both body weight loss and by reduction of nephrotoxicity, as measured by a rise in serum blood urea nitrogen (BUN), creatinine levels and by histopathologic changes, which occurred 4 days following cis-DDP treatment. The antitumor effects of cis-DDP on experimental tumor models (P388 and Gross leukemia) were not significantly altered by GSH treatment. It is suggested that the partial protection by GSH from acute toxicity of the antitumor drug is directly related to protection of renal function.

scholarly journals Seasonal effects of central leptin infusion on secretion of melatonin and prolactin and on SOCS-3 gene expression in ewes

2008 ◽  
Vol 198 (1) ◽  
pp. 147-155 ◽  
Author(s):  
D A Zieba ◽  
M Szczesna ◽  
B Klocek-Gorka ◽  
E Molik ◽  
T Misztal ◽  
...  
Keyword(s):  
Third Ventricle ◽  
Plasma Concentrations ◽  
Seasonal Effects ◽  
Cytokine Signaling ◽  
Dependent Manner ◽  
Suppressor Of Cytokine Signaling ◽  
Medial Basal Hypothalamus ◽  
Leptin Sensitivity ◽  
Dose Dependent ◽  
Short Days

Recent studies have demonstrated photoperiodic changes in leptin sensitivity of seasonal mammals. Herein, we examined the interaction of season (long days (LD) versus short days (SD)) and recombinant ovine leptin (roleptin) on secretion of melatonin and prolactin (PRL) and on mRNA expression of suppressor of cytokine signaling-3 (SOCS-3) in the medial basal hypothalamus (MBH) in sheep. Twenty-four Polish Longwool ewes, surgically fitted with third ventricle (IIIV) cannulas, were utilized in a replicated switchback design involving 12 ewes per season. Within-season and replicate ewes were assigned randomly to one of three treatments (four ewes/treatment) and infused centrally three times at 0, 1 and 2 h beginning at sunset. Treatments were 1) control, Ringer–Locke buffer; 2) L1, roleptin, 0.5 μg/kg BW; and 3) L2, roleptin, 1.0 μg/kg BW. Jugular blood samples were collected at 15-min intervals beginning immediately before the start of infusions and continued for 6 h. At the end of blood sampling, a washout period of at least 3 days elapsed before ewes were re-randomized and treated with one of the treatments described above (four ewes/treatment). Ewes were then killed and brains were collected for MBH processing. Leptin treatments increased (P<0.001) circulating leptin concentrations compared with controls during both seasons in a dose-dependent manner. Overall, mean plasma concentrations of melatonin were greater (P<0.001) during LD than SD. However, leptin treatments increased melatonin concentrations during SD in a dose-dependent manner and decreased it during LD. Similarly, plasma concentrations of PRL were greater (P<0.001) during LD than SD. However, unlike changes in melatonin, circulating PRL decreased (P<0.001) in response to leptin during LD. Semi-quantitative PCR revealed that leptin increased (P<0.001) SOCS-3 expression in the MBH region during LD in a dose-dependent manner. Data provide evidence that secretion of photoperiodic hormones such as melatonin and PRL are inversely regulated by leptin during SD and LD. However, the increase in expression of SOCS-3 in the MBH during LD compared with SD fails to fully explain these effects.

Biochemical changes and oxidative stress induced by zearalenone in the liver of pregnant rats

2014 ◽  
Vol 34 (1) ◽  
pp. 65-73 ◽  
Author(s):  
C Zhou ◽  
Y Zhang ◽  
S Yin ◽  
Z Jia ◽  
A Shan
Keyword(s):  
Oxidative Stress ◽  
Messenger Rna ◽  
Experimental Period ◽  
Normal Diet ◽  
Dependent Manner ◽  
Sprague Dawley ◽  
Pregnant Rats ◽  
Sprague Dawley Rats ◽  
Albumin Content ◽  
Dose Dependent

The aim of the present research was to examine the toxic influence of different doses of zearalenone (ZEN) on the liver, especially oxidative stress induced by ZEN on the liver. A total of 48 pregnant Sprague-Dawley rats were randomly assigned into 4 treatments groups with 12 animals in each. The rats were fed with a normal diet treated with 0 mg/kg (control), 50 mg/kg (treatment 1), 100 mg/kg (treatment 2), or 150 mg/kg (treatment 3) ZEN in feed on gestation days (GDs) 0–7 and then all the rats were fed with a normal diet on GDs 8–20. The experimental period lasted 21 days. The results showed that exposure to ZEN induced increase in aspartate amino transferase, alanine aminotransferase, and alkaline phosphatase activities and decrease in total protein and albumin content in a dose-dependent manner and also induce decrease in superoxide dismutase and glutathione peroxidase activities and increase in malondialdehyde content in a dose-dependent manner in the serum and the liver. The increased transcription of cytochrome P450 2E1 (CYP2E1) was detected in the liver after exposure to ZEN. These results suggested that ZEN not only caused damage in the liver of pregnant rats in a dose-dependent manner but also induced the messenger RNA expression of CYP2E1 in the liver.

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