Effects of central and systemic administration of leptin on neurotransmitter concentrations in specific areas of the hypothalamus

2006 ◽  
Vol 290 (2) ◽  
pp. R306-R312 ◽  
Author(s):  
Kimberly A. Clark ◽  
Sheba M. J. MohanKumar ◽  
Badrinarayanan S. Kasturi ◽  
P. S. MohanKumar
Keyword(s):  
Intraperitoneal Administration ◽  
Ventromedial Hypothalamus ◽  
Systemic Administration ◽  
Male Rats ◽  
Dependent Manner ◽  
Intracerebroventricular Administration ◽  
Dorsal Nucleus ◽  
Intracerebroventricular Injections ◽  
Dose Dependent ◽  
Pituitary Adrenal Axis

Leptin, a hormone produced by adipocytes, has been shown to affect a number of central functions, such as regulation of the hypothalamo-pituitary-adrenal axis, feeding, and body weight regulation. Because hypothalamic monoamines are intricately involved in the regulation of these functions, we hypothesized that leptin may produce its effects by altering the activity of these neurotransmitters. To test this hypothesis, male rats received peripheral (0, 100, or 500 μg ip), or central (0 or 5 μg icv) injections of leptin. The animals were killed 5 h later, and their brains were removed, frozen, and sectioned. Serum was collected to measure leptin and corticosterone by RIA. The paraventricular nucleus (PVN), arcuate nucleus (AN), ventromedial hypothalamus (VMH), dorsomedial dorsal nucleus (DMD), median eminence (ME), and medial preoptic area (MPA) were obtained using Palkovits' microdissection technique, and monoamine concentrations in these areas were determined using HPLC-EC. Intraperitoneal administration of leptin increased serum leptin concentrations in a dose-dependent manner ( P < 0.05). Both intraperitoneal and intracerebroventricular administration of leptin decreased serum corticosterone significantly ( P < 0.05). Norepinephrine (NE) concentration decreased significantly in the PVN, AN, and VMH after both intraperitoneal and intracerebroventricular administration of leptin ( P < 0.05). NE concentrations decreased significantly in the DMN after intracerebroventricular administration of leptin ( P < 0.05). Leptin treatment (both ip and icv) decreased dopamine concentrations significantly in the PVN. Serotonin (5-HT) concentration decreased significantly in the PVN after both intraperitoneal and intracerebroventricular injections of leptin and decreased in the VMH only with intracerebroventricular treatment of leptin. Leptin did not affect any of the monoamines in the ME and MPA. These results indicate that both central and systemic administration of leptin can affect hypothalamic monoamines in a region-specific manner, which, in turn, could mediate many of leptin's central and neuroendocrine effects.

scholarly journals Effects of intraperitoneal administration of gabapentin on the minimum alveolar concentration of isoflurane in adult male rats

2012 ◽  
Vol 46 (2) ◽  
pp. 108-113 ◽  
Author(s):  
D T Boruta ◽  
G Sotgiu ◽  
F J Golder
Keyword(s):  
Adult Male ◽  
Drug Testing ◽  
Minimum Alveolar Concentration ◽  
Linear Regression Analysis ◽  
Intraperitoneal Administration ◽  
Male Rats ◽  
High Dose ◽  
Dependent Manner ◽  
Clinically Significant ◽  
Dose Dependent

Gabapentin has been used to treat a variety of conditions in both human and veterinary medicine, including seizures, neuropathies and chronic pain. However, little information is known about the effects of gabapentin on the minimum alveolar concentration (MAC) of volatile anaesthetics. In this study, we investigated the effect of intraperitoneal administration of gabapentin on isoflurane MAC in adult male rats and hypothesized that gabapentin would decrease MAC in a dose-dependent manner. Using a standard MAC study protocol, we compared five treatment groups (G) receiving 0 (G0), 30 (G30), 100 (G100), 300 (G300) and 1000 (G1000) mg/kg gabapentin intraperitoneally and compared post-drug MAC values among groups and with corresponding baseline MAC values determined in each group prior to drug testing. The average baseline isoflurane MAC value was 1.45 ± 0.17%, which did not differ significantly between groups (1.47 ± 0.23% [G30], 1.46 ± 0.23% [G100], 1.48 ± 0.18% [G300] and 1.42 ± 0.2% [G1000]). In the G300 and G1000 groups, the isoflurane MAC value decreased significantly by 19% and 18%, respectively, from corresponding baseline values ( P< 0.05, when compared with G0). Linear regression analysis revealed a negative correlation between blood gabapentin concentration and percent change in MAC ( R2 = 0.43; P< 0.05) but not dose. In conclusion, high-dose intraperitoneal gabapentin decreased isoflurane MAC. However, the effect was small and not dose-dependent, and is unlikely to be clinically significant.

Evaluating the Proposed Mechanism by Which Atorvastatin Can Protect Renal Tissue against Contrast Media: An Animal study

2019 ◽  
pp. 75-84
Keyword(s):  
Contrast Media ◽  
Kidney Injury ◽  
Saline Group ◽  
Pleiotropic Effect ◽  
Renal Tissue ◽  
Male Rats ◽  
Dependent Manner ◽  
Group 2 ◽  
Dose Dependent ◽  
Media Group

Contrast- induced nephropathy (CIN) is an elevation of serum creatinine of ≥ 0.5 mg/dL from baseline after two to three days of exposure to contrast substance if there is no other cause for acute kidney injury. Atorvastatin may protect normal kidney physiology from contrast- induced kidney injury by effects unrelated to hypolipidemia termed pleiotropic effect by decline of endothelin production, angiotensin system down regulation, and under expression of endothelial adhesion molecules. This study was conducted to assess the strategy by which atorvastatin can achieve protective effect for kidneys after exposure to contrast media in an animal model. A 40 male rats were distributed randomly into 4 groups; ten rats for each: group (1): given normal saline; group (2): CIN group given iopromide as contrast media; group (3): given atorvastatin (20mg/kg) and iopromide; and group (4): given atorvastatin (40mg/kg) and iopromide. Blood collected by cardiac puncture for detection of serum glutathione, malondialdehyde, matrix metalloproteinase-9, and interleukin-18. The results have shown a significant increase in inflammatory and oxidative stress markers in contrast media group, and significant reduction in these markers in atorvastatin treated groups, in a dose-dependent manner. As conclusion, atorvastatin mechanism for protection against CIN in a dose-dependent manner can mediate by anti-inflammatory and antioxidant effects.

Evaluation of diuretic and antioxidant properties in aqueous bark and fruit extracts of pine

2020 ◽  
Vol 17 ◽  
Author(s):  
Hadi Shariati ◽  
Mohammad Hassanpour ◽  
Gholamreza Sharifzadeh ◽  
Asghar Zarban ◽  
Saeed Samarghandian ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Phenolic Content ◽  
Antioxidant Properties ◽  
Pine Bark ◽  
Male Rats ◽  
Total Phenolic ◽  
Dependent Manner ◽  
Aqueous Extracts ◽  
Antioxidant Power ◽  
Dose Dependent

Objective: The present study has been carried out to evaluate the diuretic and antioxidant properties of pine herb in an animal model. Materials and Methods: 45 adult male rats were randomly divided into nine groups including: groups I (the negative control), groups II (positive control, furosemide 10 mg/kg), groups III to VIII (treatment groups received 100, 200, 400 mg/kg of the aqueous extracts of bark and fruit) and group IX received the combination of aqueous extract of bark (100 mg/kg) and the fruit (100 mg/kg). The urine output, glomerular filtration rate (GFR), electrolytes, urea, and creatinine levels were evaluated . Furthermore, the phenolic content and antioxidant activity of both extracts were also assessed using 2, 2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and Folin–Ciocalteu methods. Results: The aqueous extracts of the pine bark and fruit increased the urinary output in a dose-dependent manner. The combination of the two extracts compared to the other extracts alone significantly increased the serum potassium level. This study also showed each extract increase creatinine clearance in a dose-dependent manner (p<0.01 and p<0.05). The increase of GFR in the combination group was not significant. The current data showed a significant increase in the total phenolic content in pine bark extract in compared with the fruit extract. Conclusion: The pine bark and fruit can be useful in the prevention and treatment of kidney stones due to the high antioxidant activity.

scholarly journals Antidiarrheal Activity of Dissotis multiflora (Sm) Triana (Melastomataceae) Leaf Extract in Wistar Rats and Subacute Toxicity Evaluation

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Alian Désiré Afagnigni ◽  
Maximilienne Ascension Nyegue ◽  
Chantal Florentine Ndoye Foe ◽  
Youchahou Njankouo Ndam ◽  
Frédéric Nico Njayou ◽  
...  
Keyword(s):  
Wistar Rats ◽  
Leaf Extract ◽  
Shigella Flexneri ◽  
Female Rats ◽  
Male Rats ◽  
Dependent Manner ◽  
Subacute Toxicity ◽  
Antidiarrheal Activity ◽  
Dose Dependent ◽  
Ethanolic Leaf Extract

The present work was undertaken to evaluate antidiarrheal activity of ethanolic leaf extract of Dissotis multiflora (Sm) Triana (D. multiflora) on Shigella flexneri-induced diarrhea in Wistar rats and its subacute toxicity. Diarrhea was induced by oral administration of 1.2 × 109 cells/mL S. flexneri to rats. Antidiarrheal activity was investigated in rats with the doses of 111.42 mg/kg, 222.84 mg/kg, and 445.68 mg/kg. The level of biochemical parameters was assessed and organs histology examined by 14 days’ subacute toxicity. S. flexneri stool load decreased significantly in dose-dependent manner. The level of ALT increased (p<0.05) in male rats treated with the dose of 445.68 mg/kg while creatinine level increased in rats treated with both doses. In female rats, a significant decrease (p<0.05) of the level of AST and creatinine was noted in rats treated with the dose of 222.84 mg/kg of D. multiflora. Histological exams of kidney and liver of treated rats showed architectural modifications at the dose of 445.68 mg/kg. This finding suggests that D. multiflora leaf extract is efficient against diarrhea caused by S. flexneri but the treatment with doses lower than 222.84 mg/kg is recommended while further study is required to define the exact efficient nontoxic dose.

scholarly journals Preclinical Study on the Ameliorating Effect of L-Ascorbic Acid for the Oxidative Stress of Caused by Chronic Administration of Organic Nitrates in Cardiovascular Diseases

2021 ◽  
Author(s):  
Ahmed M Hamdan ◽  
Zuhair M. Mohammedsaleh ◽  
Aalaa Aboelnour ◽  
Sherif M.H. Elkhannishi
Keyword(s):  
Oxidative Stress ◽  
Lipid Peroxidation ◽  
Ascorbic Acid ◽  
Chronic Administration ◽  
Stress Factors ◽  
Male Rats ◽  
Oxidative Stress Marker ◽  
Organic Nitrates ◽  
Dependent Manner ◽  
Dose Dependent

Abstract PurposeThe therapeutic activity of Glyceryl trinitrate (GTN) is mainly regulated by liberating nitric oxide (NO) and reactive nitrogen species (RNS). During this biotransformation, oxidative stress and lipid peroxidation inside the red blood cells (RBCs) occur. The principal objective of our research is to explain the ameliorating effect of L-ascorbic acid for the deleterious effects of chronic administration of nitrovasodilator drugs. MethodsWe studied some biochemical parameters for the oxidative stress using groups of high sucrose/fat (HSF) diet Wistar male rats chronically orally administered ISMN. Afterwards, we evaluated the role of L-ascorbic acid against these biochemical changes. ResultsChronic treatment with organic nitrates caused elevated serum levels of lipid peroxidation, hemoglobin derivatives as methemoglobin and carboxyhemoglobin, rate of hemoglobin autoxidation, the cellular levels of pro-inflammatory cytokines marker (NF-κB) and apoptosis markers (caspase-3) in myocardium muscles in a dose dependent manner. Meanwhile, such exposure caused decline in the enzymatic effect of superoxide dismutase (SOD), glutathione (GSH) and catalase activity (CAT) accompanied with a decrease of in the level of mitochondrial oxidative stress marker (nrf2) in myocardium muscles and decrease in the serum iron and total iron binding capacity (TIBC) in a dose dependent manner. Concomitant treatment with L-ascorbic acid significantly diminished these changes for all examined parameters.ConclusionChronic administration of organic nitrates leads to the alteration of the level of oxidative stress factors in the myocardium tissue due to generation of reactive oxygen species. Using vitamin C can effectively ameliorate such intoxication to overcome the nitrate tolerance.

scholarly journals The Effect of the mGlu8 Receptor Agonist, S-3,4-DCPG on Acquisition and Expression of Morphine-induced Conditioned Place Preference in Male rats

2021 ◽  
Author(s):  
Nazanin Kahvandi ◽  
Zahra Ebrahimi ◽  
Seyed Asaad Karimi ◽  
Siamak Shahidi ◽  
Iraj Salehi ◽  
...  
Keyword(s):  
Conditioned Place Preference ◽  
Metabotropic Glutamate Receptors ◽  
Preference Test ◽  
Place Preference ◽  
Male Rats ◽  
Dependent Manner ◽  
Metabotropic Glutamate ◽  
Male Wistar Rats ◽  
Dose Dependent

Abstract Background: The nucleus accumbens (NAc) plays a principal role in drug reward. It has been reported that metabotropic glutamate receptors (mGlu receptors) play a key role in the rewarding pathway(s). Previous studies have shown the vast allocation of the different types of mGlu receptors, including mGlu8 receptors, in regions that are associated with opioid rewards, such as the NAc. The aim of the present study was to evaluate the role of mGlu8 receptors within the NAc in the acquisition and expression phases of morphine induced conditioned place preference (CPP). Adult male Wistar rats were bilaterally implanted by two cannulas' in the NAc and were evaluated in a CPP paradigm. Selective mGlu8 receptor allosteric agonist (S-3,4-DCPG) was administered at doses of 0.03, 0.3, and 3 μg/0.5 μL saline per side into the NAc on both sides during the 3 days of morphine (5 mg/kg) conditioning (acquisition) phase, or before place preference test, or post-conditioning (expression) phase of morphine-induced CPP. Results: The results revealed that intra-accumbal administration of S-3,4-DCPG (0.3 and 3 μg) markedly decreased the acquisition in a dose-dependent manner but had no effect on expression of morphine-induced CPP. Conclusions: The findings suggest that activation of mGlu8 receptors in the NAc dose-dependently blocks the establishment of morphine-induced CPP and reduces the rewarding properties of morphine which may be related to the glutamate activity into the NAc and in reward pathway(s). These data suggest that mGlu8 receptor may be involved in conditioned morphine reward.

Evaluation of Hepatoprotective activity of Methanol extract of Persicaria hydropiper: An in vivo screening

2021 ◽  
pp. 5819-5824
Author(s):  
Pooja Kamra ◽  
Mahaveer Singh ◽  
Hardarshan Singh Lamba ◽  
Birendra Srivastava
Keyword(s):  
Carbon Tetrachloride ◽  
Intraperitoneal Administration ◽  
Hepatoprotective Activity ◽  
Dependent Manner ◽  
Standard Drug ◽  
Whole Plant ◽  
Dose Dependent ◽  
Histopathological Investigation ◽  
Different Doses

The present study aimed to evaluate the hepatoprotective potential of methanolic whole plant extract of Persicaria hydropiper in carbon tetrachloride (CCl4) induced hepatotoxicity model. Hepatotoxicity was induced in rats by intraperitoneal administration of carbon tetrachloride (CCl4) for seven days. The extract was thereafter administered at two different doses of 200 mg/kg and 400 mg/kg body weight for next seven days. Silymarin was used as a reference standard. The extract revealed hepatoprotective activity in dose dependent manner. The dose of 400 mg/kg exhibited maximum hepatoprotective ability as apparent from several evaluation parameters including liver function profile, bilirubin, antioxidant enzymes as well as histopathological investigation which was comparable to the standard drug Silymarin respectively. These findings sustenance the use of the extract as an adjuvant with existing therapy for treatment of liver ailments.

scholarly journals Phenyl N -tert-butylnitrone, a Free Radical Scavenger, Reduces Mechanical Allodynia in Chemotherapy-induced Neuropathic Pain in Rats

2010 ◽  
Vol 112 (2) ◽  
pp. 432-439 ◽  
Author(s):  
Hee Kee Kim ◽  
Yan Ping Zhang ◽  
Young Seob Gwak ◽  
Salahadin Abdi
Keyword(s):  
Neuropathic Pain ◽  
Free Radical ◽  
Mechanical Allodynia ◽  
Intraperitoneal Administration ◽  
Free Radical Scavenger ◽  
Radical Scavenger ◽  
Dependent Manner ◽  
Sprague Dawley ◽  
Sprague Dawley Rats ◽  
Dose Dependent

Background Paclitaxel is a widely used chemotherapeutic drug for breast and ovarian cancer. Unfortunately, it induces neuropathic pain, which is a dose-limiting side effect. Free radicals have been implicated in many neurodegenerative diseases. The current study tests the hypothesis that a free radical scavenger plays an important role in reducing chemotherapy-induced neuropathic pain. Methods Neuropathic pain was induced by intraperitoneal injection of paclitaxel (2 mg/kg) on four alternate days (days 0, 2, 4, and 6) in male Sprague-Dawley rats. Phenyl N-tert-butylnitrone (PBN), a free radical scavenger, was administered intraperitoneally as a single dose or multiple doses before or after injury. Mechanical allodynia was measured by using von Frey filaments. Results The administration of paclitaxel induced mechanical allodynia, which began to manifest on days 7-10, peaked within 2 weeks, and plateaued for at least 2 months after the first paclitaxel injection. A single injection or multiple intraperitoneal injections of PBN ameliorated paclitaxel-induced pain behaviors in a dose-dependent manner. Further, multiple administrations of PBN starting on day 7 through day 15 after the first injection of paclitaxel completely prevented the development of mechanical allodynia. However, an intraperitoneal administration of pbn for 8 days starting with the first paclitaxel injection did not prevent the development of pain behavior. Conclusions This study clearly shows that PBN alleviated mechanical allodynia induced by paclitaxel in rats. Furthermore, our data show that PBN given on days 7 through 15 after the first paclitaxel injection prevented the development of chemotherapy-induced neuropathic pain. This clearly has a clinical implication.

Glucocorticoid sensitivity of interleukin-1 agonist and antagonist secretion: the effects of age and gender

2000 ◽  
Vol 278 (4) ◽  
pp. R855-R862 ◽  
Author(s):  
Jane M. Daun ◽  
Richard W. Ball ◽  
Joseph G. Cannon
Keyword(s):  
Mononuclear Cells ◽  
Interleukin 1 ◽  
Dependent Manner ◽  
Basal Secretion ◽  
Peripheral Blood Mononuclear ◽  
Age Related ◽  
Agonist And Antagonist ◽  
And Gender ◽  
Dose Dependent ◽  
Pituitary Adrenal Axis

Interleukin-1 (IL-1) is a primary mediator of inflammation that is regulated, in part, by the hypothalamic-pituitary-adrenal axis. The purpose of this study was to determine if gender- or age-related differences exist in the sensitivity of IL-1-producing cells to hydrocortisone. Peripheral blood mononuclear cells (PBMC) isolated from men and women (21–77 yr old) were incubated with hydrocortisone (0, 50, 100, 500, or 1,000 ng/ml) with or without lipopolysaccharide (LPS). Secretion of IL-1β and IL-1 receptor antagonist was inhibited in a dose-dependent manner ( P = 0.001) without age- or gender-related differences. Hydrocortisone decreased soluble IL-1 receptor type II (sIL-1RII) secretion by unstimulated cells ( P = 0.0001), but it increased secretion by LPS-stimulated cells ( P = 0.0001) in all groups. Unstimulated cell supernatants from men contained greater concentrations of sIL-1RII than the supernatants from women ( P= 0.011). Compared with men, PBMCs from women were less responsive to hydrocortisone inhibition of sIL-1RII secretion, regardless of age ( P = 0.001), and compared with the follicular phase, sIL-1RII secretion was lower in the luteal phase of the menstrual cycle ( P < 0.05). These data indicate that basal secretion and glucocorticoid modulation of sIL-1RII secretion by cultured PBMCs are gender dependent. Moreover, glucocorticoid influences on sIL-1RII secretion depend on the presence or absence of gram-negative bacterial toxins.

scholarly journals Effects of Orally Consumed Rosa damascena Mill. Hydrosol on Hematology, Clinical Chemistry, Lens Enzymatic Activity, and Lens Pathology in Streptozotocin-Induced Diabetic Rats

Molecules ◽  
2019 ◽  
Vol 24 (22) ◽  
pp. 4069
Author(s):  
İlker Demirbolat ◽  
Cansu Ekinci ◽  
Fadime Nuhoğlu ◽  
Murat Kartal ◽  
Pelin Yıldız ◽  
...  
Keyword(s):  
Diabetes Mellitus ◽  
Enzymatic Activity ◽  
Aldose Reductase ◽  
Clinical Chemistry ◽  
Intraperitoneal Administration ◽  
Diabetic Rats ◽  
Rosa Damascena ◽  
Dependent Manner ◽  
Chronic Hyperglycemia ◽  
Dose Dependent

Diabetes mellitus is a multisystemic metabolic disorder that may affect the eyes, kidneys, vessels, and heart. Chronic hyperglycemia causes non-enzymatic glycation of proteins and elevation of the polyol pathway resulting in oxidative stress that damages organs. The current study aimed to investigate the dose-dependent effects of orally consumed Rosa damascena Mill. hydrosol on hematology, clinical biochemistry, lens enzymatic activity, and lens pathology in streptozotocin (STZ)-induced diabetic rats. Diabetes was induced into male Sprague–Dawley rats by intraperitoneal administration of STZ (40 mg/kg body weight). Rose hydrosols containing 1515 mg/L and 500 mg/L total volatiles (expressed as citronellol) were introduced to rats orally for 45 days. Consumption of 1515 mg/L volatile containing rose hydrosol successfully ameliorated hematologic, hepatic, and renal functions. Hydrosols also attenuated hyperglycemia and decreased the advanced glycation end-product formation in a dose-dependent manner. Rose hydrosol components significantly increased the lens enzymatic activities of glutathione peroxidase and decreased the activity of aldose reductase to prevent cataractogenesis. Histopathological examinations of rat lenses also indicated that increasing the dose of rose hydrosol had a protective effect on lenses in diabetic conditions. Additionally, in silico modeling of aldose reductase inhibition with rose hydrosol volatiles was carried out for extrapolating the current study to humans. The present results suggest that rose hydrosol exerts significant protective properties in diabetes mellitus and has no toxic effect on all studied systems in healthy test groups.

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