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Journal Article 2010; 31(4): 538-548 PubMed PMID: 20802458 Citation  Keywords:  Analysis of Variance, Animals, Body Weight, Male, Maze Learning:physiology, Noise, Rats, Rats, Wistar, Reversal Learning:physiology, Spatial Behavior:physiology, Stress, Physiological:physiology, Stress, Psychological:physiopathology,.   

OBJECTIVE: This study investigated the cognitive effect of chronic exposure to environmental noise on RAWM performance of juvenile rats, and the ability of adult rats exposed to a novel acute stress to perform in the RAWM as a function of whether or not they were exposed to environmental noise as juveniles.

METHODS: We examined the consequences of exposure to noise during the juvenile-early periadolescent period on adulthood stress response by assessing cognitive performance in the RAWM. Male rats were exposed to environmental noise during the childhood-prepubescent period (21-35 PND), and their RAWM performance was tested at the end of the exposure to noise, and then again two months later when they had to cope with a new stressful event. RAWM execution included a 3-day training phase and a reversal learning phase on day 4. Escape latency, reference memory errors and working memory errors were compared between experimental and control groups. In addition, body weight gain and serum corticosterone levels were evaluated.

RESULTS: Stressed rats demonstrated spatial impairment, as evidenced by poor execution on day 4. This effect was significantly noticeable in the doubly stressed group. Noise annoyance was evidenced by reduced body weight gain and increased serum corticosterone levels.

CONCLUSIONS: Our results suggest that environmental noise may produce potent stress-like effects in developing subjects that can persist into adulthood, affecting spatial learning abilities. This cognitive impairment may restrict the subject's ability to learn under a new spatial configuration....

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Journal Article 2010; 31(3): 406-412 PubMed PMID: 20588248 Citation  Keywords:  Animals, Body Weight:drug effects, Eating:drug effects, Ghrelin:metabolism, Male, Shrews:anatomy & histology, Stomach:anatomy & histology,.   

OBJECTIVE: To investigate the distribution of ghrelin, an important appetite regulatory factor related to obesity, in the stomach of Suncus murinus, and attempted to elucidate the ghrelin-mediated regulatory effect in this animal.

METHODS: The stomachs of Suncus murinus were divided into 5 sections, cardia, fundus, greater curvature, lesser curvature, and pylorus, for investigating the ghrelin-producing cells by immunohistochemistry and Western blotting. Then Suncus murinus were randomized into two groups with ghrelin intraperitoneal injection (ghrelin-ip group) and saline intraperitoneal injection (control group), respectively. The effects of food intake and body weight were measured, and furthermore, the distribution of ghrelin in stomach was also investigated by immunohistochemistry and Western blotting.

RESULTS: The immunolocalization and protein levels of ghrelin differed significantly in different regions of the stomach of Suncus murinus. Furthermore, ghrelin administration did not change the rate of food intake, but resulted in an increase in body weight compared with the control group. In this study, we elucidated the distribution of ghrelin-producing cells in the stomach of Suncus murinus in detail for the first time. Ghrelin intraperitoneal administration was found to induce an increase in body weight without changing food intake in this species.

CONCLUSION: Our study implied ghrelin showed a different regulatory function in Suncus murinus from other species. It is considered that ghrelin may be associated with obesity-resistance phenomenon in Suncus murinus....

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Journal Article 2010; 31(3): 313-318 PubMed PMID: 20588243 Citation  Keywords:  Animals, Antioxidants:pharmacology, Blood Glucose:drug effects, Body Weight:drug effects, Carbolines:pharmacology, Diabetes Mellitus, Experimental:drug therapy, Glycosylation End Products, Advanced:metabolism, Kidney:drug effects, Male, Oxidative Stress:d.   

OBJECTIVES: Recent basic research and clinical data have provided new insights into the role of glycoxidative and nitrosative stresses (both oxidative stress) in diabetic complications, such as diabetic nephropathy, suggesting a different and innovative approach to antioxidant therapy. In streptozotocin-induced diabetic rat kidney, the present study investigated the effects of the synthetic pyridoindole antioxidant stobadine (STB) on renal total antioxidant potential (AOP) and protein oxidation parameters such as protein carbonyl content (PCC), advanced oxidation protein products (AOPPs) and nitrotyrosine (NT), a marker specific for protein modification by peroxynitrite.

MATERIALS AND METHODS: Wistar Albino rats were divided into two groups: normal and streptozotocin-induced diabetic rats. Each group of the animals was further divided into two groups: untreated and treated with stobadine (24.7 mg/kg) during 16 weeks daily by oral gavage.

RESULTS: The renal tissue AOP and the levels of AOPPs, PCC and NT were increased in diabetic rats compared with the untreated control animals. Furthermore, stobadine treatment significantly decreased protein carbonylation and AOPPs but not NT.

CONCLUSIONS: These findings indicate that STB is an antioxidant factor which can improve glycoxidative stress markers in kidney, while it has no effect on protein nitrosylation....

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Journal Article 2009; 30(6): 761-768 PubMed PMID: 20038927 Citation  Keywords:  Acoustic Stimulation, Age Factors, Animals, Animals, Newborn, Anxiety, Separation:immunology, Apoptosis:immunology, Body Weight, Cells, Cultured, Corticosterone:blood, Disease Models, Animal, Female, Immune Tolerance:physiology, Lymphocytes:cytology, Male.   

OBJECTIVES: Different inbred mouse strains but also each animal of the same strain show an individually different stress response which is influenced by genetic and environmental factors such as early life experiences. In this study, we investigated consequences of mild postnatal stress exposure on the stress coping style of adult BALB/c mice.

METHODS: We used a model of mild early life stress where neonatal mice were repeatedly separated from the dam staying with their siblings for 1-h each day during the first two postnatal weeks. The environment during maternal separation was adapted to the nest (bedding, 37 degrees C warm).

RESULTS: Adult female BALB/s mice that underwent the maternal separation protocol or were not isolated from the dam in early life were exposed to combined acoustic and restraint stress in adulthood. Repeated maternal separation which was performed under ambient conditions increased the stress coping ability of mice at the age of 12 weeks when exposed to this psychological stressors. By acoustic and restraint stress-induced alterations such as high corticosterone levels, an anti-inflammatory immune conditioning with an ex vivo hyperinducibility of interleukin-10 of splenocytes and a massive loss of body weight were significantly reduced in the maternally separated group compared with conventionally bred control mice.

CONCLUSIONS: Mild maternal separation in early life modifies the stress coping style of adult female BALB/c mice to a more stress-resistant phenotype which shows reduced repeated stress-induced immune suppression and weight loss and is linked to reduced release of glucocorticoids after stress exposure....

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Journal Article 2009; 30(Suppl 1): 242-247 PubMed PMID: 20027178 Citation  Keywords:  Animals, Body Size:drug effects, Body Weight:drug effects, Czech Republic, Dose-Response Relationship, Drug, Herbicides:administration & dosage, Kidney:drug effects, Rivers, Toxicity Tests, Triazines:administration & dosage, Water Pollutants:administratio.   

OBJECTIVES: The aim of this study was to investigate effects of subchronic exposure to sublethal levels of terbutryn on growth and on histopathological changes in Danio rerio.

DESIGN: The acute toxicity tests were performed on the juvenile stage of Danio rerio according to OECD No. 203 Fish, Acute Toxicity Test. The juvenile growth tests were performed on D. rerio according to the OECD method No. 215. Fish at the age of 20 days were exposed to the terbutryn environmental concentration commonly detected in the Czech rivers (0.02 microg L-1) and the range of sublethal concentrations of terbutryn (0.06, 0.2, 0.6 and 2 mg L-1) for 28 days.

RESULTS: The 96hLC50 terbutryn mean value for the juvenile stage of D. rerio was 5.71 +/- 0.46 mg L-1. A significant decrease (p < 0.01) in the fish growth caused by terbutryn was observed in the concentration of 0.6 mg L-1. The value of NOEC was 0.2 mg L-1 and LOEC was 0.6 mg L-1 of terbutryn. We found the damage to tubular system of kidneys in the concentration of 0.6 mg L-1 of terbutryn.

CONCLUSION: The environmental concentration of terbutryn in the Czech rivers did not have any effects on growth and on histopathological changes in D. rerio and this concentration is lower than determined LOEC and NOEC values of terbutryn....

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Journal Article 2009; 30(2): 256-261 PubMed PMID: 19675512 Citation  Keywords:  Adolescent, Adolescent Development:drug effects, Age of Onset, Antipsychotic Agents:adverse effects, Body Weight:drug effects, Female, Humans, Male, Psychotic Disorders:drug therapy, Retrospective Studies, Schizophrenia:drug therapy, Time Factors, Weight .   

OBJECTIVES: The aim of the study was to assess weight changes associated with certain atypical (AAP) and typical (TAP) antipsychotic drugs in patients with early-onset schizophrenia and other related psychotic disorders.

METHODS: Our retrospective study included 109 patients (52 boys, 57 girls) with a mean age of 15.8 +/- 1.6 years. The patients were evaluated based to their medical records prior to starting therapy, and then after 1, 3, and 6 weeks of treatment.

RESULTS: During the first week of treatment, the AAP group (n = 85; risperidone, olanzapine, ziprasidone, and clozapine) gained 1.5% of baseline weight whereas the TAP group (n = 24; haloperidol, perphenazine, and sulpiride) gained only 0.2% (p = 0.049). Differences in relative changes between the two groups were not significant at weeks 3 and 6. Expressed as absolute values, patients in our sample gained an average of 3.4 kg (SD 3.2) on AAP and 2.0 kg (SD 3.9) on TAP during 6 weeks of treatment (p = 0.335). Only the risperidone, olanzapine, and clozapine groups had sufficient numbers of patients to allow a comparison at the endpoint of the study (week 6). The patients gained, on average, 3.6 kg (SD 2.6) on risperidone, 4.4 kg (SD 2.5) on olanzapine, and 2.1 kg (SD 4.0) on clozapine during the six weeks of treatment (p = 0.286).

CONCLUSIONS: In our study, we did not find a difference in weight gain between the AAP and TAP groups, as large as has been described in the literature. It also seems plausible that the unique and variable weight changes associated with individual AAPs in the pediatric population are different from those observed in the adult population....

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Journal Article 2008; 29(5): 784-789 PubMed PMID: 18987608 Citation  Keywords:  Acetylcholine:metabolism, Animals, Blood Pressure:drug effects, Body Weight:drug effects, Cardiovascular Physiological Phenomena:drug effects, Enzyme Inhibitors:pharmacology, Feedback, Physiological:drug effects, Hypertension:drug therapy, Isometric Contr.   

OBJECTIVES: The effect of 8-week-lasting low-dose treatment of NG-Nitro-L-arginine methyl ester (L-NAME), a nitric oxide (NO) synthase inhibitor, was investigated in borderline hypertensive rats (BHR) to examine, whether dose of 1.5 mg/kg/day affects feedback regulation of NO synthesis.

METHODS: Blood pressure (BP) of 12 weeks old Wistar and BHR rats was determined non-invasively by tail-cuff. NO synthase (NOS) activity was determined by conversion of [3H]-L-arginine to [3H]-L-citrulline in the aorta, left ventricle (LV) and hypothalamus. Vascular function of the femoral artery was determined using Mulvany's myograph in isometric conditions.

RESULTS: Chronic low-dose L-NAME treatment of BHR induced sustained blood pressure elevation and left ventricular hypertrophy associated with the decrease in NOS activity in left ventricle and unaltered NOS activity in the aorta. By contrast, the improvement of LV and aortic NOS activity was found in Wistar rats. In hypothalamus, no changes in NOS activity were found in both BHR and Wistar. In Wistar, acetylcholine-induced relaxation of the femoral artery was increased and serotonin-induced and noradrenalin-induced constriction were reduced in L-NAME treated group. These effects, however, were not seen in BHR.

CONCLUSION: The results indicate that NOS/NO feedback regulation works differently under conditions of normotension and prehypertension. Low-dose L-NAME treatment accentuated NO production in normotensive rats, but it failed to improve NOS activity in BHR....

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Journal Article 2008; 29(4): 421-427 PubMed PMID: 18766154 Citation  Keywords:  Anorexia Nervosa:blood, Body Weight, Female, Hormones:blood, Humans, Retrospective Studies, Weight Loss,.   

OBJECTIVES: Body weight loss in patients with anorexia nervosa (AN) is accompanied by a number of hormonal and metabolic disorders. The scope and intensity of these disorders may have a considerable influence on the prognosis in this disease. The goal of the study was an evaluation of selected diagnostic examinations in comparison with clinical data of female patients with AN.

PATIENTS & METHODS: Retrospective studies involved eighty-seven (87) patients with AN. On therapy commencement, routine laboratory tests (full blood cell count, serum concentrations of sodium, potassium, glucose, cholesterol, triglycerides, total calcium, phosphates, total protein and the urea) and hormonal tests (TSH, TSH, FT4, FT3, E2, T, cortisol measured at 8(00), 17(00) and 24(00), LH and FSH in stimulation test with GnRH) were performed in each patient. Correlations were determined between clinical data and the measured hormone concentrations.

RESULTS: In the studied girls, the mean values of routine laboratory tests, performed at the beginning of the therapy, were within the normal ranges (except hypernatremia). The mean concentrations of LH, FSH and FT4 were below reference values; the mean concentration of cortisol considerably exceeded the standard range. Statistically significant relations were demonstrated between BMI values and the concentrations of LH, E2 and cortisol.

CONCLUSIONS: Body weigh loss is not significantly reflected by abnormal results of routinely performed laboratory tests. Hypogonadotropic hypogonadism and hypercortisolemia are the most characteristic hormonal symptoms in girls with AN....

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