Spatio-temporal distribution of fatty acid-binding protein 6 (fabp6) gene transcripts in the developing and adult zebrafish (Danio rerio)

We have determined the structure of the fatty acid-binding protein 6 (fabp6) gene and the tissue-specific distribution of its transcripts in embryos, larvae and adult zebrafish (Danio rerio). Like most members of the vertebrate FABP multigene family, the zebrafish fabp6 gene contains four exons separated by three introns. The coding region of the gene and expressed sequence tags code for a polypeptide of 131 amino acids (14 kDa, pI 6.59). The putative zebrafish Fabp6 protein shared greatest sequence identity with human FABP6 (55.3%) compared to other orthologous mammalian FABPs and paralogous zebrafish Fabps. Phylogenetic analysis showed that the zebrafish Fabp6 formed a distinct clade with the mammalian FABP6s. The zebrafish fabp6 gene was assigned to linkage group (chromosome) 21 by radiation hybrid mapping. Conserved gene synteny was evident between the zebrafish fabp6 gene on chromosome 21 and the FABP6/Fabp6 genes on human chromosome 5, rat chromosome 10 and mouse chromosome 11. Zebrafish fabp6 transcripts were first detected in the distal region of the intestine of embryos at 72 h postfertilization. This spatial distribution remained constant to 7-day-old larvae, the last stage assayed during larval development. In adult zebrafish, fabp6 transcripts were detected by RT-PCR in RNA extracted from liver, heart, intestine, ovary and kidney (most likely adrenal tissue), but not in RNA from skin, brain, gill, eye or muscle. In situ hybridization of a fabp6 riboprobe to adult zebrafish sections revealed intense hybridization signals in the adrenal homolog of the kidney and the distal region of the intestine, and to a lesser extent in ovary and liver, a transcript distribution that is similar, but not identical, to that seen for the mammalian FABP6/Fabp6 gene. © 2008 The Authors.

Localization of myosin-Va in subpopulations of cells in rat endocrine organs

Myosin-Va is a Ca 2+/calmodulin-regulated unconventional myosin involved in the transport of vesicles, membranous organelles, and macromolecular complexes composed of proteins and mRNA. The cellular localization of myosin-Va has been described in great detail in several vertebrate cell types, including neurons, melanocytes, lymphocytes, auditory tissues, and a number of cultured cells. Here, we provide an immunohistochemical view of the tissue distribution of myosin-Va in the major endocrine organs. Myosin-Va is highly expressed in the pineal and pituitary glands and in specific cell populations of other endocrine glands, especially the parafollicular cells of the thyroid, the principal cells of the parathyroid, the islets of Langerhans of the pancreas, the chromaffin cells of the adrenal medulla, and a subpopulation of interstitial testicular cells. Weak to moderate staining has been detected in steroidogenic cells of the adrenal cortex, ovary, and Leydig cells. Myosin-Va has also been localized to non-endocrine cells, such as the germ cells of the seminiferous epithelium and maturing oocytes and in the intercalated ducts of the exocrine pancreas. These data provide the first systematic description of myosin-Va localization in the major endocrine organs of rat. © 2008 Springer-Verlag.

Root surface treatment with vitamin C in tooth replantation: microscopic study in rats

AIM: Late tooth replantation is a worthy procedure, especially in growing patients, being the best option for tooth avulsion. This study evaluated the effects of root surface treatment with 2% acidulated phosphate sodium fluoride and effervescent vitamin C (Redoxon) in late replantation. METHODS: Twenty rat teeth (Rattus norvegicus, albinus, Wistar) were extracted and left on a table for 6 h. Then, the dental papilla and enamel organ were sectioned and the pulp was removed through the apex. After removal of the periodontal ligament with a blade, the animals were divided into 2 groups: Group I teeth were immersed in 2% acidulated phosphate sodium fluoride solution for 10 min and obturated with Ca(OH)(2) paste. Group II teeth were immersed in effervescent vitamin C solution (Redoxon 2 g) for 10 min and obturated as for Group I. After these procedures, teeth were replanted and animals were killed after 60 days. RESULTS: The study revealed a larger amount of replacement resorption in Group I and larger amount of ankylosis in Group II, with statistically significant difference and absence of inflammatory resorption. CONCLUSION: The substances used for root surface treatment were unable to prevent replacement resorption and ankylosis, which are expected when the periodontal ligament has been lost.

Efeito hipotensor do extrato aquoso de alpiste (Phalaris canariensis L.) em ratos

The plant species Phalaris canariensis, known as canary grass, is widely used in folk medicine as diuretic, as well as in culinary and animal feed. In this study, the effect of P. canariensis aqueous extract (AE) on water flow (V) and sodium renal excretion (Qe (Na+)) was evaluated in anesthetized Wistar rats. Arterial pressure alterations (AP) were also assessed. Two groups were studied: Control group (CON) - oral administration of 1.0 mL distilled water, and Experimental group (EA) - oral administration of 1.0 mL P. canariensis aqueous extract 40%. Rats were anesthetized and subjected to cannulation of trachea (for better pulmonary ventilation), left carotid artery (for arterial pressure measurement) and urinary bladder (for urine collection). Control animals did not present significant alterations (p>0.05) in all analyzed parameters after water administration. EA group had a significant arterial pressure reduction at 60 minutes (31.4%) and 90 minutes (49.1%) after the extract administration (p<0.05). Renal parameters did not have any significant alteration (p>0.05). In this study, P. canariensis aqueous extract had a hypotensive effect in anesthetized Wistar rats, without renal alterations.

Biological response to wollastonite doped α-tricalcium phosphate implants in hard and soft tissues in rats

The biological response following subcutaneous and bone implantation of β-wollastonite(β-W)-doped α-tricalcium phosphate bioceramics in rats was evaluated. Tested materials were: tricalcium phosphate (TCP), consisting of a mixture of α- and β-polymorphs; TCP doped with 5 wt. % of β-W (TCP5W), composed of α-TCP as only crystalline phase; and TCP doped with 15 wt. % of β-W (TCP 15), containing crystalline α-TCP and β-W. Cylinders of 2×1 mm were implanted in tibiae and backs of adult male Rattus norvegicus, Holtzman rats. After 7, 30 and 120 days, animals were sacrificed and the tissue blocks containing the implants were excised, fixed and processed for histological examination. TCP, TCP5W and TCP15W implants were biocompatible but neither bioactive nor biodegradable in rat subcutaneous tissue. They were not osteoinductive in connective tissue either. However, in rat bone tissue β-W-doped α-TCP implants (TCP5W and TCP 15W) were bioactive, biodegradable and osteoconductive. The rates of biodegradation and new bone formation observed for TCP5W and TCP15W implants in rat bone tissue were greater than for non-doped TCP.

Modificações no periodonto de ratos diabéticos após a movimentação ortodôntica

Aim: The aim of this study was to evaluate the periodontal ligament changes after induced dental movement of the upper incisor in diabetic rats. Methods: Twenty Wistar rats (Rattus norvegicus) with 105 days of age were used. The rats were divided in four groups: C - normoglicemic animals not submitted to dental movement; CAO - normoglicemic animals submitted to dental movement; D - diabetic animals not submitted the dental movement; DAO - diabetic animals submitted to dental movement. The animals had remained with dental movement devices during 5 days. The number of sanguine vessels and the thickness of the periodontal ligament were evaluated at cervical, medium and apical histological cut regions. Results and Conclusion: At tension side, the dental movement in the animals of group CAO resulted in a thicker periodontal ligament (17.64% apical, 39.28% medium, 51.35% cervical) when compared to C group (p < 0.05 for medium and cervical area). Group DAO exhibited an increase of periodontal ligament thickness of 50.55% (apical), 48.14% (average) and 50% (cervical) when compared to group D (p < 0.05). The periodontal ligament sanguine vessels number did not differed significantly for all groups (p < 0.05). At tension side, bone reabsorption lacunae were observed in CAO, D and DAO groups. The pressure side was not examined in this study phase.

Metabolic syndrome signs in Wistar rats submitted to different high-fructose ingestion protocols

In search of an adequate model for the human metabolic syndrome, the metabolic characteristics of Wistar rats were analysed after being submitted to different protocols of high fructose ingestion. First, two adult rat groups (aged 90 d) were studied: a control group (C1; n 6) received regular rodent chow (Labina, Purina) and a fructose group (F1; n 6) was fed on regular rodent chow. Fructose was administered as a 10 % solution in drinking water. Second, two adult rat groups (aged 90 d) were evaluated: a control group (C2; n 6) was fed on a balanced diet (AIN-93G) and a fructose group (F2; n 6) was fed on a purified 60 % fructose diet. Finally, two young rat groups (aged 28 d) were analysed: a control group (C3; n 6) was fed on the AIN-93G diet and a fructose group (F3; n 6) was fed on a 60 % fructose diet. After 4-8 weeks, the animals were evaluated. Glucose tolerance, peripheral insulin sensitivity, blood lipid profile and body fat were analysed. In the fructose groups F2 and F3 glucose tolerance and insulin sensitivity were lower, while triacylglycerolaemia was higher than the respective controls C2 and C3 (P < 0.05). Blood total cholesterol, HDL and LDL as well as body fat showed change only in the second protocol. In conclusion, high fructose intake is more effective at producing the signs of the metabolic syndrome in adult than in young Wistar rats. Additionally, diet seems to be a more effective way of fructose administration than drinking water.

Tratamento hepatoprotetor favorece a resposta leucocitária de ratos wistar intoxicados por CCL4

The aims of this investigation was to evaluate the effect of hepatoprotective treatments with a compound prepared by the association of N-Acetyl DL-Methionine (5%) + Choline chloride (2%) + Caffeine (1%) + Thiamine hydrochloride (1%) + Nicotinamida (0,5%)+ Pyridoxine hydrochloride (0.04%), administered through intramuscular (IM) route, at doses of 0.2, 0.6 and 1.0 mL/kg of BW, through the study of leukocytes responses in rats submitted to acute intoxication with CCl4. 147 females were randomized into 21 groups, performing five different treatments, which were evaluated seven animals in four periods: two, four, six and eight days after CCl4-induced intoxication. In this study, it was observed absolute eosinophilia and monocytosis in animals untreated and treated with the lowest dose of 0.2 mL. These responses were significantly better in animals treated with 0.6 and 1.0 mL/ kg BW. The untreated animals showed thrombocytopenia, when compared to treated animals. Absolute neutropenia and lymphocytosis was observed in all rats intoxicated with CCl4, there is no difference among treatments. The analysis of white blood cells demonstrated that the hepatoprotective treatments favored the leukocyte response, by act beneficially on the population of these cells, supporting the hypothesis that these events may reduce the deleterious effects in liver tissue after intoxication by CCl4.

Alterações reprodutivas em ratos machos expostos perinatalmente aos frutos da Solanum lycocarpum

This work employed pregnant rats treated with Solanum lycocarpum unripe fruits (10% in diet) from gestation day (GD) 06 to post-natal day (PND) 07, for the evaluation of the sperm number, daily sperm production and epididymal sperm transit time of the male offspring at PND 60 and PND 90. No differences were observed in the daily sperm production (DSP) and sperm number in the testis of the exposed males at PND 60 and PND 90. Also, no alterations were observed in sperm transit time in the caput epididymis of the exposed males at PND 60 and PND 90. However, a reduced sperm transit time was observed in the corpus/cauda epididymis of the experimental males at PND 90. The last data may explain the reduced sperm number observed in the corpus/cauda epididymis of the experimental male rats at PND 90. These data show that the male rats exposed to S. lycocarpum fruits during gestation did not present alterations in testis sperm production and number, however the sperm transit time through epididymis was impaired, resulting in a decreased number of spermatozoa in epididymis cauda. We conclude that S. lycocarpum may cause imbalance on hypothalamus-pituitary gland axis.

Amifostine reduces the seminiferous epithelium damage in doxorubicin-treated prepubertal rats without improving the fertility status

Background: Amifostine is an efficient cytoprotector against toxicity caused by some chemotherapeutic drugs. Doxorubicin, a potent anticancer anthracycline, is known to produce spermatogenic damage even in low doses. Although some studies have suggested that amifostine does not confer protection to doxorubicin-induced testicular damage, schedules and age of treatment have different approach depending on the protocol. Thus, we proposed to investigate the potential cytoprotective action of amifostine against the damage provoked by doxorubicin to prepubertal rat testes (30-day-old) by assessing some macro and microscopic morphometric parameters 15, 30 and 60 days after the treatment; for fertility evaluation, quantitative analyses of sperm parameters and reproductive competence in the adult phase were also carried out.Methods: Thirty-day-old male rats were distributed into four groups: Doxorubicin (5 mg/kg), Amifostine (400 mg/kg), Amifostine/Doxorubicin (amifostine 15 minutes before doxorubicin) and Sham Control (0.9% saline solution). Standard One Way Anova parametric and Anova on Ranks non-parametric tests were applied according to the behavior of the obtained data; significant differences were considered when p < 0.05.Results: The rats killed 30 and 60 days after doxorubicin treatment showed diminution of seminiferous epithelium height and reduction on the frequency of tubular sections containing at least one type of differentiated spermatogonia; reduction of sperm concentration and motility and an increase of sperm anomalous forms where observed in doxorubicin-treated animals. All these parameters were improved in the Amifostine/Doxorubicin group only when compared to Doxorubicin group. Such reduction, however, still remained below the values obtained from the Sham Control group. Nevertheless, the reproductive competence of doxorubicin-treated rats was not improved by amifostine pre-administration.Conclusions: These results suggest that amifostine promotes a significant reduction of the doxorubicin long-term side effects on the seminiferous epithelium of prepubertal rats, which is reflected in the epidydimal fluid parameters in the adult phase. However, fertility status results suggest that such protection may not be effective against sperm DNA content damage. Further investigation of sperm DNA integrity must be carried out using amifostine and doxorubicin-treated experimental models. © 2010 Vendramini et al; licensee BioMed Central Ltd.

Chronic alcohol intake upregulates hepatic expression of carotenoid cleavage enzymes and PPAR in rats

Excessive and chronic alcohol intake leads to a lower hepatic vitamin A status by interfering with vitamin A metabolism. Dietary provitamin A carotenoids can be converted into vitamin A mainly by carotenoid 15,15′-monooxygenase 1 (CMO1) and, to a lesser degree, carotenoid 9′10′-monooxygenase 2 (CMO2). CMO1 has been shown to be regulated by several transcription factors, such as the PPAR, retinoid X receptor, and thyroid receptor (TR). The regulation of CMO2 has yet to be identified. The impact of chronic alcohol intake on hepatic expressions of CMO1 and CMO2 and their related transcription factors are unknown. In this study, Fischer 344 rats were pair-fed either a liquid ethanol Lieber-DeCarli diet (n = 10) or a control diet (n = 10) for 11 wk. Hepatic retinoid concentration and expressions of CMO1, CMO2, PPARγ, PPARα, and TRβ as well as plasma thyroid hormones levels were analyzed. We observed that administering alcohol decreased hepatic retinoid levels but increased mRNA concentrations of CMO1, CMO2, PPARγ, PPARα, and TRβ and upregulated protein levels of CMO2, PPARγ, and PPARα. There was a positive correlation of PPARγ with CMO1(r = 0.89; P<0.0001) and both PPARγ and PPARα with CMO2 (r = 0.72, P< 0.001 and r = 0.62, P< 0.01, respectively). Plasma thyroid hormone concentrations did not differ between the control rats and alcohol-fed rats. This study suggests that chronic alcohol intake significantly upregulates hepatic expression of CMO1 and, to a much lesser extent, CMO2. This process may be due to alcohol-induced PPARγ expression and lower vitamin A status in the liver. © 2010 American Society for Nutrition.

Evaluations hematological and biochemical by the use of sodium diclofenac, meloxicam and firocoxib in rats

This work has evaluated the hematological and biochemical profile by the use of sodium diclofenac, meloxicam and firocoxib in Wistar rats. The rats were distributed in groups: G1 (control), G2 (diclofenac sodium: 15 mg/kg), G3 (meloxicam: 2.0 mg/ kg), G4 (meloxicam: 10.0 mg/ kg), G5 (firocoxib: 5.0 mg/ kg) e G6 (firocoxib: 25.0 mg/ kg). The drugs were administered intragastrically (gavage) once a day, during five days and evaluated in three moments: M1 (48 hours after the beginning of the treatment), M2 (96 hours after the beginning of the treatment) and M3 (72 hours after the ending of the treatment). In each moment of each group, five to seven animals were evaluated and laboratory exams were performed. There were no significant changes observed in the biochemical and hematological parameters by the use of meloxicam and firocoxib. One of the effects of the sodium diclofenac was eritrogram variation as hematocrit, erythrocytes, hemoglobin decrease during the treatment. In addition, the platelets and total white blood cells counts did not change except for basophil. There was no changes in AST, ALP, GGT, urea, creatinine, sodium, potassium values. However, the values of protein, globulin and albumin decreased. It was concluded that diclofenac sodium does not provide large variations in the hemogram and biochemical profile than the meloxicam and firocoxib do not provide delletery effects in laboratories tests.

Exercise training ameliorates the impairment of endothelial and nitrergic corpus cavernosum responses in diabetic rats

Aims: The effect of exercise training (ET) on vascular responsiveness in diabetes mellitus has been largely well studied. However, limited studies have investigated the effects of ET on functional responses of the corpus cavernosum (CC) in diabetic animals. Therefore, the aim of this study was to investigate whether prior ET prevents the impairment of erectile function in streptozotocin-induced diabetic rats. Main methods: Rats were exercised for four weeks prior to the induction of diabetes, and then again for another 4 weeks thereafter. Concentration-response curves to acetylcholine, sodium nitroprusside, Y-27632, BAY 412272 and phenylephrine (PE) were obtained in CC. The excitatory and inhibitory effects of electrical-field stimulation were also evaluated. Key findings: Plasma SOD levels were markedly decreased in the sedentary diabetic group (D-SD) as compared to control sedentary animals (C-SD), approximately 53% (P < 0.05) and this reduction was restored in trained diabetic animals. Physical training restored the impairment of endothelium-dependent and -independent relaxation responses seen in the D-SD group. The potency values for Y-27632 in the CC were significantly reduced in the D-SD group, which was reversed by physical training. The impairment of electrical-field stimulation (EFS)-induced relaxation seen in the D-SD group was restored by physical training. On the other hand, both EFS-induced contractions and concentration-response curves to PE in cavernosal strips were not modified by either diabetes or physical training. Significance: Practice of regular physical exercise may be an important approach in preventing erectile dysfunction associated with diabetes mellitus by re-establishment of the balance between NO production and its inactivation. © 2010 Elsevier Inc. All rights reserved.

Perinatal exposure to parasiticide ivermectin: Long-term effects on reproductive parameters of adult male rats

Ivermectin is one of the most widely used antiparasitic drugs globally. The aim of this study was to evaluate the chronic effects of perinatal exposure to ivermectin on male reproductive parameters in rats. Pregnant rats were treated daily by oral gavage with 0.4 or 1.6 mg kg -1 of ivermectin or vehicle, from gestational day 6 until post-natal day 10. In the adulthood stage, there were significant reductions in the relative testicular weight of rats exposed to the low dose and in relative prostate weight of male rats exposed to the high dose of ivermectin. Furthermore, the animals exposed to the low dose also presented an increased seminal vesicle weight compared to controls. However, neither of the ivermectin doses interfered in daily sperm production, sperm number in testis, or sexual behavior of exposed males. In conclusion, perinatal exposure to ivermectin neither altered the male reproductive system development markedly, nor produced any adverse effects on the parameters evaluated. © 2011 Taylor & Francis.

Long-term ethanol consumption promotes hepatic tumorigenesis but impairs normal hepatocyte proliferation in rats

Chronic and excessive alcohol consumption has been related to an increased risk of several cancers, including that of the liver; however, studies in animal models have yet to conclusively determine whether ethanol acts as a tumor promoter in hepatic tumorigenesis. We examined whether prolonged alcohol consumption could act as a hepatic tumor promoter after initiation by diethylnitrosamine (DEN) in a rat model. Male Sprague-Dawley rats were injected with 20 mg DEN/kg body weight 1 wk before introduction of either an ethanol liquid diet or an isoenergic control liquid diet. Hepatic pathological lesions, hepatocyte proliferation, apoptosis, PPARα and PPARγ, and plasma insulin-like growth factor 1 (IGF-1) levels were assessed after 6 and 10 mo. Mean body and liver weights, plasma IGF-1 concentration, hepatic expressions of proliferating cellular nuclear antigen and Ki-67, and cyclin D1 in ethanol-fed rats were all significantly lower after 10 mo of treatment compared with control rats. In addition, levels of hepatic PPARγ protein, not PPARα, were significantly higher in the ethanol-fed rats after prolonged treatment. Although ethanol feeding also resulted in significantly fewer altered hepatic foci, hepatocellular adenoma was detected in ethanol-fed rats at 10 mo, but not in control rats given the same dose of DEN. Together, these results indicate that chronic, excessive ethanol consumption impairs normal hepatocyte proliferation, which is associated with reduced IGF-1 levels, but promotes hepatic carcinogenesis. © 2011 American Society for Nutrition.