The cytotoxicity effect of bismuth oxide particles synthesized hydrothermally using different reaction temperatures in vitro.

INTRODUCTION: Bismuth oxide (Bi2O3) particles gained attention in preclinical research especially in medical imaging. Bismuth oxide with its long circulation time is an alternative to the current iodine contrast media which directly possesses high X-ray attenuation coefficient. Exploration of bismuth compound is hampered owing to challenges in synthesizing control for in vivo stability. MATERIALS AND METHODS: This study aimed are to characterize Bi2O3 particles synthesized at 60, 90 and 120 °C via hydrothermal method and investigated cytotoxicity of cell viability assay, cell morphology analysis, intracellular reactive oxygen species (ROS) assay and expression of ER stress genes by real-time PCR. RESULTS: Results indicated that the size of rod-shaped Bi2O3 particles increased with rising synthesizing temperatures. The cytotoxicity of Bi2O3 particles in Chang liver cells was size-dependent. Bigger-sized Bi2O3 particles resulted in lesser toxicity effects. mRNA expressions of GRP78 and C/EBP homologous protein (CHOP) were down-regulated in all treated Chang liver cells due to the increasing size of Bi2O3 particles. Bi2O3 particles synthesized at 120 °C was found to be less toxic than iodine. CONCLUSION: Data suggested that the response of Chang liver cells to Bi2O3 particle cytotoxicity has a significant relationship with its reaction temperatures. This outcome is important in hazard assessment of Bi2O3 particles as a new contrast media and provides better understanding in synthesizing control to enhance its biocompatibility.

Insulin resistance in patients on valproic acid: relation to adiponectin.

OBJECTIVES: To investigate the presence of insulin resistance in obese children with idiopathic epilepsy on valproic acid (VPA) monotherapy in comparison to obese otherwise healthy subjects. Secondary outcome was to explore the relation between adiponectin and insulin resistance among those patients. MATERIALS AND METHODS: Fifty obese children with generalized idiopathic epilepsy on VPA monotherapy and a control group of 49 obese clinically healthy age and sex-matched children with simple obesity were recruited in the study. Anthropometric assessment, fasting plasma insulin (FI), fasting glucose (FG) and fasting adiponectin levels were measured. Fasting glucose insulin ratio (FGIR) and homoeostasis model assessment for insulin resistance (HOMA-IR) were calculated for both patients and control subjects. Measurement of serum VPA trough level was also performed in patients. RESULTS: Patients had significantly higher fasting blood glucose, fasting insulin, lower FGIR and higher HOMA-IR values, compared to controls. Mean adiponectin level was significantly lower in patients compared to controls. The duration of treatment with valproic acid negatively correlated with adiponectin (r = -0.285, P = 0.045), but did not correlate with fasting glucose, insulin, FGIR or HOMA-IR. Total daily VPA dose significantly correlated with fasting insulin (r = 0.495, P < 0.001), FGIR (r = -0.525, P < 0.001) and HOMA-IR (r = 0.404, P = 0.004). CONCLUSION: This study ascertains the relationship between dose and duration of VPA therapy, insulin resistance and the adipocytokine axis. We are reporting the novel proposal that obese VPA-treated children are more insulin resistant and have lower adiponectin levels than obese and otherwise healthy children.

DYSMICROBISM, INFLAMMATORY BOWEL DISEASE AND THYROIDITIS: ANALYSIS OF THE LITERATURE.

The human body is colonized by a large number of microbes that are collectively referred to as the microbiota. They interact with the hosting organism and some do contribute to the physiological maintenance of the general good health thru regulation of some metabolic processes while some others are essential for the synthesis of vitamins and short-chain fatty acids. The abnormal variation, in the quality and/or quantity of individual bacterial species residing in the gastro-intestinal tract, is called “dysmicrobism”. The immune system of the host will respond to these changes at the intestinal mucosa level which could lead to Inflammatory Bowel Diseases (IBD). This inflammatory immune response could subsequently extend to other organs and systems outside the digestive tract such as the thyroid, culminating in thyroiditis. The goal of the present study is to review and analyze data reported in the literature about thyroiditis associated with inflammatory bowel diseases such as Ulcerative Colitis (UC) and Crohn’s Disease (CD). It was reported that similarities of some molecular bacterial components with molecular components of the host are considered among the factors causing IBD through an autoimmune reaction which could involve other non-immune cell types. The axis dysmicrobism-IBD-autoimmune reaction will be investigated as a possible etiopathogenic mechanism to Autoimmune Thyroiditis. If such is the case, then the employment of specific probiotic strains may represent a useful approach to moderate the immune system.

Impact of anthropometric measures and serum leptin on severity of gastroesophageal reflux disease.

The aim of this prospective study was to evaluate the impact of obesity, determined by different anthropometric measures, on clinical and endoscopic severity of GERD and the relation between serum leptin and clinical and endoscopic severity of GERD in Egyptian patients. The study was carried out at Ain Shams University Hospitals and Theodor Bilharz Research Institute, Cairo, Egypt. A total of 60 patients with clinically and endoscopically evident gastroesophageal reflux disease (GERD) were enrolled in this study as well as 20 healthy subjects matched for age and gender serving as the control group. Patients were divided according to their body mass index (BMI) into two groups: group 1 (n = 30): overweight and obese (BMI ≥ 25 and/or waist-to-height ratio [WHtR] ≥ 0.5) and group 2 (n = 30): normal weight (BMI ≥ 18 to < 25 and/or WHtR ≥ 0.4 to < 0.5). Upper gastrointestinal endoscopy, anthropometric measures, and symptom severity score questionnaire were done for all patients. Serum leptin hormone was assessed for patients and control groups.The evidence revealed statistically significant difference between the two groups in terms of different anthropometric measures (P < 0.00) except the height (P < 0.9), abdominal fat depot equations (P < 0.00), endoscopic findings according to Los Angeles classification (P < 0.001), symptom severity score (P < 0.00), and serum leptin hormone (43.96 ± 23.50 in group 1 vs. 7.5133 ± 8.18294 in group 2 and 6.98 ± 5.90 in the control group) (P = 0.00). Obesity in general and central (abdominal) obesity specifically has significant impact on clinical and endoscopic severity of GERD. Increased leptin hormone level is associated with clinical and endoscopic severity of GERD. Future trial on larger number of patients is emphasized.

Dataset of bird's eye chilies farm for stereo image semantic segmentation.

This paper presents a dataset of bird's eye chilies in a single farm for semantic segmentation. The dataset is generated using two cameras that are aligned left and right forming a stereo-vision video capture. By analyzing the disparity between corresponding points in the left and right images, algorithms can calculate the relative distance of objects in the scene. This depth information is useful in various applications, including 3D reconstruction, object tracking, and autonomous navigation. The dataset consists of 1150 left and right compressed images extracted from ten sets of stereo videos taken at ten different locations within the chili farm from the same ages of the bird's eye chilies. Since the dataset is used for semantic segmentation, the ground truth images of manually semantic segmented images are also provided in the dataset. The dataset can be used for 2D and 3D semantic segmentation of the bird's eye view chili farm. Some of the object classes in this dataset are the sky, living things, plantation, flat, construction, nature, and misc.

Endovascular therapy for patients with renal angiomyolipoma presenting with retroperitoneal haemorrhage.

We report our experience treating four patients with acutely bleeding angiomyolipoma (AML) of sizes between 4 and 12 cm who were managed with endovascular embolisation with a mean follow-up of 10 months. In our case series, we demonstrate that endovascular embolisation in the acute setting for bleeding AMLs is a viable treatment option. AML should be in the differential diagnosis of acutely bleeding renal masses, even when there is no fat assessed by computed tomography (CT) imaging in the renal mass.

Author Correction: Magneto-Hybrid Nanofluids Flow via Mixed Convection past a Radiative Circular Cylinder.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Magneto-Hybrid Nanofluids Flow via Mixed Convection past a Radiative Circular Cylinder.

The goal of the current analysis is to scrutinize the magneto-mixed convective flow of aqueous-based hybrid-nanofluid comprising Alumina and Copper nanoparticles across a horizontal circular cylinder with convective boundary condition. The energy equation is modelled by interpolating the non-linear radiation phenomenon with the assisting and opposing flows. The original equations describing the magneto-hybrid nanofluid motion and energy are converted into non-dimensional equations and solved numerically using a new hybrid linearization-Chebyshev spectral method (HLCSM). HLCSM is a high order spectral semi-analytical numerical method that results in an analytical solution in η-direction and thereby the solution is valid in overall the η-domain, not only at the grid points. The impacts of diverse parameters on the allied apportionment are inspected, and the fallouts are described graphically in the investigation. The physical quantities of interest containing the drag coefficient and the heat transfer rate are predestined versus fundamental parameters, and their outcomes are elucidated. It is witnessed that both drag coefficient and Nusselt number have greater magnitude for Cu-water followed by hybrid nanofluid and Al2O3-water. Moreover, the value of the drag coefficient declines versus the enlarged solid volume fraction. To emphasize the originality of the current analysis, the outcomes are compared with quoted works, and excellent accord is achieved in this consideration.

Lymphadenectomy in colorectal cancer liver metastases resection: incidence of hilar lymph nodes micrometastasis.

BACKGROUND: Liver resection is considered the best treatment for metastatic colorectal cancer. Several prognostic factors have been investigated, and many studies have shown that hepatic hilum lymph nodes involvement has a negative impact on prognosis. The present study evaluated the frequency of microscopic involvement of hilar lymph nodes, through systematic lymphadenectomy and analysis of micrometastases in patients undergoing hepatectomy due to colorectal metastasis. METHODS: A total of 28 patients underwent hepatic resection with hilar lymphadenectomy. Lymph nodes considered negative by conventional hematoxylin and eosin (H&E) staining were analyzed by serial sectioning with 100-microm intervals and immunohistochemistry (IHC) with anti-human pancytokeratin antibody AE1/AE3. RESULTS: In average, 6.18 lymph nodes were dissected per patient. No morbidity or mortality was associated to lymphadenectomy. In two patients, conventional H&E analysis showed presence of microscopic lymph node metastasis. IHC analysis allowed the identification of three other patients with lymph node micrometastases. The overall frequency of microscopic metastases, including micrometastasis, was 18%. CONCLUSIONS: Systematic lymphadenectomy allowed the detection of microscopic lymph node metastases, resulting in more accurate staging of extrahepatic disease. The inclusion of IHC increased the detection of lymph node micrometastasis.

Post-lymphangiographic computed tomography in chylothorax after esophagogastrectomy: a case report.

Chylothorax is a rare complication of thoracic surgery. Lymphangiography has long been considered to be the standard of reference for diagnosis and post-treatment evaluation while the role of post-lymangiographic CT is debated. We report a case of chylothorax in a 68-year-old male following esophagogastrectomy for which conservative treatment and thoracic duct ligation failed. Lymphangiography performed after these attempts revealed persistent thoracic duct leakage into the right pleural space. Subsequent non-contrast CT and reformatted images clearly depicted the sources of leakage, and this documentation targeted direct percutaneous treatment. Unfortunately, the lack of access precluded the planned percutaneous CT-guided embolization of the thoracic duct. Nevertheless, this case suggests that post- lymphangiographic CT can serve as a value-added modality in the evaluation and potential treatment of chylothorax.

Smoking increases salivary arginase activity in patients with dental implants.

It is believed that an increased arginase activity may lead to less nitric oxide production, which consequently increases the susceptibility to bacterial infection. Considering the hypothesis that smoking may alter the arginase activity and that smoking is considered a risk factor to dental implant survival, the present study aimed at evaluating the effect of smoking on the salivary arginase activity of patients with dental implants. Salivary samples of 41 subjects were collected: ten non-smoking and with no dental implants (group A), ten non-smoking subjects with dental implants (group B), ten smoking subjects with implants (group C), and 11 smoking subjects with no dental implants (group D). The levels of salivary arginase activity were determined by the measurement of L-ornithine and expressed as mIU/mg of protein. A significant increase in the salivary arginase activity was verified in groups C (64.26 +/- 16.95) and D (49.55 +/- 10.01) compared to groups A (10.04 +/- 1.95, p = 0.00001 and p = 0.0110, groups C and D, respectively) and B (11.77 +/- 1.45, p = 0.00001 and p = 0.0147, groups C and D, respectively). No significant difference was found between groups C and D (p = 0.32). Within the limits of the present study, it can be concluded that salivary arginase activity is increased in smoking subjects with dental implants in contrast to non-smoking subjects with dental implants, therefore suggesting a possible mechanism by which cigarette smoking may lead to implant failure. The analysis of salivary arginase activity may represent an important tool to prevent implant failure in the near future.

Pediatric liver transplantation: comparison between results from deceased and living related transplantation.

Timely access to a living donor has reduced pretransplant mortality in pediatric liver transplantation. We hypothesized that this strategy may provide better posttransplant outcomes, due to shorter waiting times on the transplant list. A extensive search in the medical literature from the last 10 years showed clear evidence of the benefits of living donors, namely, decreased dropout rates as well as the chance to transplant the patients in better clinical situation. However, a negative impact was related to the higher morbidity rates when compared to whole grafts from deceased donors.

Direct trans-cervical endolymphatic thoracic duct stent-graft for plastic bronchitis.

Plastic bronchitis is a poorly understood and uncommon diagnosis, arising from multiple etiologies. Traditional treatment consists of steroids and vasodilators, with thoracic duct embolization emerging as a new procedural therapy. Herein, abnormal lymphatic vessels were noted on lymphangiography in an adult patient with debilitating plastic bronchitis, but anterograde lymphatic access was not feasible due to the patient's morbid obesity and non-visualization of retroperitoneal lymphatics. After trans-venous thoracic duct access could not be established, direct trans-cervical thoracic duct access was performed. A thoracic duct stent-graft was placed, excluding the abnormal bronchial lymphatics and maintaining physiologic anterograde flow through the central lymphatics. At three-month follow-up, the patient's condition had resolved.

Evaluation of molecular markers in hepatic metastasis of colorectal adenocarcinoma.

BACKGROUND/AIMS: There were 49 patients studied, coming from The Liver Unit at the "Hospital das Clinicas da Faculdade de Medicina da USP (N=41) and from "Prof. Dr. Angelita Habr-Gama and Joaquim Gama-Rodrigues Surgery Institute", SP (N=8); all of which had hepatic metastasis of colorectal adenocarcinoma, with no evidence of concurrent metastasis in any other organs and were submitted to surgical treatment, during the period of 1992 to 2002, with the aim of analyzing the immunoexpression of the p53, ki-67, p16 and molecular markers in order to relate the disease-free period with the prognosis. METHODOLOGY: The patient's clinical data were analyzed retrospectively for verification of information such as age, gender, size of the hepatic metastasis and/or the largest lesion, number of satellite nodules resected and compromised, margin of resection free from neoplasia. RESULTS: The immunoexpression of the p53 was associated with the shortest period of life free from disease (p = 0.04). The proliferation marker ki-67 was not associated with the reduction of the disease-free interval and survival; the immunoexpression of the proliferation marker p16 was not associated with the reduction of disease-free period and survival, however, it was associated with hepatic metastasis synchronism. In patients who received postoperative systemic chemotherapy with 5-FU and leucovorin, the immunoexpression on the hepatic metastasis was not associated with a longer disease-free interval. CONCLUSIONS: Molcular markers may be useful to evaluate hepatic metastasis of colorectal Adenocarcinoma.

Two-year outcomes of balloon-occluded retrograde transvenous obliteration of gastric varices in liver transplant recipients: A multi-institutional study.

PURPOSE: To assess the 2-year effectiveness and safety of balloon-occluded retrograde transvenous obliteration (BRTO) for gastric varices (GVs) in liver transplant recipients. MATERIALS AND METHODS: Eleven liver transplant recipients underwent consecutive BRTO for GVs at four institutions. Patients included eight (73%) men and three (27%) women with mean age of 56 years±12 (SD) (range: 26-67 years). Underlying cause of liver transplantation was hepatitis C virus (HCV)-related cirrhosis in five (45%), alcohol- and HCV-related cirrhosis in three (27%), primary biliary cirrhosis in two (18%), and alcoholic cirrhosis in one (9%). Five (45%) patients underwent BRTO for actively bleeding GVs, three (17%) for high-risk GVs, and three (17%) for augmentation of portal venous flow through obliteration of gastrorenal shunts. Mean time between liver transplantation and BRTO was 78 months (range: 0.1-276 months). Technical success, GVs obliterative rates, and immediate complications were recorded. Post-BRTO hemorrhagic, transplant, and overall survival rates were evaluated at 6, 12, and 24 months. RESULTS: All (100%) procedures were technically successful. Complete GVs obliteration was achieved in ten patients (91%). Two major complications (18%) occurred in the immediate post-procedure period. One patient developed complete portal vein thrombosis, and another patient developed consumptive coagulopathy, ultimately leading to death. No post-BRTO hemorrhagic recurrences were seen at 6, 12, or 24 months. One patient (9%) had delayed upper gastrointestinal bleeding at 34 months after the procedure which was managed conservatively. Transplant and overall survival rates were 91% at 6, 12, and 24 months. CONCLUSION: BRTO has high technical success and complete GVs obliterative rates in liver transplant recipients with few complications and high graft survival rates.

The main hepatic anatomic variations for the purpose of split-liver transplantation.

BACKGROUND/AIMS: Variant hepatic anatomy must be recognized and appropriately managed during split-liver transplantation to ensure complete vascular and biliary supply to both grafts. The aim of this study was to demonstrate the importance of an assessment of the hepatic anatomical structures for the purpose of split-liver transplantation. MATERIAL AND METHODS: Human cadaveric livers (n = 60) were obtained during routine autopsies. The cadavers and the livers had to comply with the following requirements: (1) minimum age 18 years, (2) no liver pathology expected from medical history, and (3) no liver pathology noted at autopsy. Resections were carried out en bloc with liver, celiac trunk, left gastric artery, lesser omentum, superior mesenteric artery, and head of the pancreas. The main anatomical structures of the liver as hepatic artery, portal vein, biliary tree, and hepatic veins were dissected and correlated hepatic segments for the application of liver splitting. RESULTS: The right the median, and the left hepatic veins were unique, with in 59 (98.3%), 53 (88.3%) and 46 (76.3%) cases, respectively. The portal vein trunk divided into right and left branches in 59 (98.3%) cases. A median branch appeared in 9 (15.2%) cases and no bifurcation of the portal vein occurred in 1 (1.6%) case. The right and left hepatic ducts were multiple in 47 (78.3%) and 57 (95%) cases, respectively, however, the median, hepatic duct was unique in 16 (26.6%) cases. Examining the intrahepatic distribution of the right hepatic duct, we found 4 branches in 28 (59%) cases (segments V, VI, VII, and VIII) 2 branches in 11 (23%) cases, (segments V and VI) and 2 branches in 8 (17%) cases (segments VII and VIII). Fifty-seven cadavers had multiple left hepatic ducts. The intrahepatic dissection showed that the distribution of the major branches were toward hepatic segments II and III. Three separate branches of the left hepatic duct were found in 11 (19%) cases (segments II, III, and IV). Two intrahepatic ducts coming from hepatic segments V and VI drained separately into the left intrahepatic biliary tree in 1 (2%) case. The arterial supply of the liver was by right and left hepatic artery with only 9 (15%) cases there being median hepatic artery. The right hepatic artery, coming from the superior mesenteric artery, was present in 15 (25%) cases and a left hepatic artery originating from the left gastric artery in only 2 (3.3%) cases. The left hepatic artery had 2 exceptional origins, in 1 (1.6%) case coming directly from the abdominal aorta and in the other from the superior mesenteric artery. The right and left hepatic artery was accessory, in 11 (18.3%) and 2 (3.3%) cases, respectively. The right hepatic artery was dominant in 4 (6.6%) cases. The median hepatic artery was directed to segment IV in 6 (10%) cases and to segment II and III in 3 (4.9%) cases. CONCLUSION: The study showed that the technique of controlled liver splitting for transplantation in 2 recipients is an acceptable method to increase the number of liver allografts. The anatomical and technical details of the splitting procedure are critical for the success of this technique. Good graft function and avoidance of complications depend on each graft having an intact arterial and portal blood supply as well as biliary and venous drainage from all retained liver segments. The absence of a bifurcation of the portal vein is a rare anomaly and would certainly contraindicate a partition.

Outcomes of Percutaneous Management of Anastomotic Ureteral Strictures in Renal Transplantation: Chronic Nephroureteral Stent Placement with and without Balloon Dilatation.

PURPOSE: This study was designed o evaluate outcomes of percutaneous management of anastomotic ureteral strictures in renal transplants using nephroureteral stents with or without balloon dilatation. METHODS: A retrospective audit of 1,029 consecutive renal transplants was performed. Anastomotic ureteral strictures were divided into two groups: nephroureteral stent only (NUS) and NUS+PTA (nephroureteral stent plus percutaneous transluminal angioplasty), with each cohort subdivided into early versus late presentation (obstructive uropathy occurring <90 day or >90 days from transplant, respectively). Overall and 6-month technical success were defined as removal of NUS any time with <30 % residual stenosis (any time lapse less or more than 6 months) and at >6 months, respectively. Patency was evaluated from NUS removal to last follow-up for both groups and compared. RESULTS: Sixty-seven transplant patients with 70 ureteric anastomotic strictures (6.8 %, n = 70/1,029) underwent 72 percutaneous treatments. 34 % were late (>90 days, n = 24/70), and 66 % were early (<90 days, n = 46/70). Overall technical success was 82 % (n = 59/72) and 6-month success was 58 % (n = 42/72). Major and minor complications were 2.8 % (n = 2/72), and 12.5 % (n = 9/72). NUS+PTA did not improve graft survival (p = 0.354) or patency (p = 0.9) compared with NUS alone. There was no difference in graft survival between treated and nontreated groups (p = 0.74). CONCLUSIONS: There is no advantage to PTA in addition to placement of NUS, although PTA did not negatively impact graft survival or long-term patency and both interventions were safe and effective. Neither the late or early groups benefited from PTA in addition to NUS. Earlier obstructions showed greater improvement in serum creatinine than later obstructions.

Evidence for a role of prolactin in prostate and seminal vesicle growth in immature male rats.

To determine if prolactin secreted endogenously by anterior pituitary grafts could augment male accessory organ weights, single anterior pituitary grafts were placed under the kidney capsule of male rats, whereas control animals received a graft of muscle. Three weeks after transplantation, the animals were sacrificed by decapitation and a significant increase in plasma prolactin was observed, which was accompanied by a highly significant increase in the weights of seminal vesicles, ventral and dorsal prostates, and adrenals. To determine the importance of testicular steroids in the response, animals were castrated. The increases in prolactin, seminal vesicle and ventral and dorsal prostate weights still occurred whether or not a small dose of testosterone replacement therapy was employed. In the presence of the pituitary graft, adrenal weight usually increased in these animals as well. To rule out a requirement for adrenal steroids in the response, adrenalectomized-castrate animals were also studied, and the increases in prolactin and prostate weights still occurred although there was no significant increase in the size of the seminal vesicles. To rule out the participation of other pituitary hormones, pituitary grafts were also placed in hypophysectomized animals, and in these animals, there was also a significant increase in prolactin, accessory sex organ and testicular weights, but the adrenals did not increase in size. The grafts failed to alter gonadotropin titers in any experiment. It is concluded that single anterior pituitary grafts are capable of secreting sufficient prolactin to increase the size of the sex accessories and sometimes the testes and adrenals of the rat. Furthermore, the effects on the male sex accessory organs were demonstrable in the absence of testicular or both testicular and adrenal steroids. The data suggest that prolactin may play a physiological role in the growth of the testes, adrenals and sex accessories.

Imidazoline receptors of the paraventricular nucleus on the pressor response induced by stimulation of the subfornical organ.

In the present experiments we investigated a possible involvement of imidazoline receptors of the paraventricular nucleus (PVN) of the hypothalamus on the pressor effects of the angiotensin II (ANG II) injected into the subfornical organ (SFO), in male Holtzman rats (250-300 g) with a cannula implanted into the third ventricle (3rdV), PVN and SFO. At first we tested the participation of alpha 2 and imidazoline agonist and antagonist compounds on the pressor effect of ANG II injected into the 3rdV. Based on the results we may conclude that clonidine associated with rilmenidine was able to block the hypertensive response to ANG II. The ANG II (20 pmol) injected into SFO induced a robust increase in blood pressure (37 +/- 2 mmHg). Isotonic saline (0.15 M) NaCl did not produce any change in blood pressure (5 +/- 2 mmHg). The injection of rilmenidine (30 micrograms/kg/1 microL), an imidazoline agonist agent injected into PVN before ANG II injection into SFO, blocked the pressor effect of ANG II (5 +/- 2 mmHg). Also, the injection of idazoxan (60 micrograms/kg/microL) before rilmenidine blocked the inhibitory effect of rilmenidine on blood pressure (39 +/- 4 mmHg). The injection of clonidine (20 nmol/microL) prior to ANG II into the 3rdV produced a decreased in arterial blood pressure (37 +/- 2 mmHg) to (15 +/- 4 mmHg). The injection of yohimbine (80 nmol/microL) prior to clonidine blocked the effect of clonidine on the effect of ANG II (27 +/- 2 mmHg). The injection of rilmenidine prior to ANG II also induced a decrease in arterial blood pressure (10 +/- 3 mmHg). The injection of idazoxan prior to rilmenidine also blocked the inhibitory effect of rilmenidine (24 +/- 3 mmHg). In summary, the present study demonstrated that rilmenidine decreases the hypertensive effect of ANG II, with more potency than clonidine, even when injected into 3rdV or PVN. This study established that the PVN interacts with SFO by imidazoline receptors in order to control the arterial blood pressure.

Ibotenate lesion of the medial hypothalamus alters the salt intake and pressor responses to activation of the median preoptic nucleus in rats.

We investigated the influence of ibotenic acid lesions of the medial hypothalamus (MH) on salt appetite and arterial blood pressure responses induced by angiotensinergic and adrenergic stimulation of the median preoptic nucleus (MnPO) of rats. Previous injection of the adrenergic agonists norepinephrine, clonidine, phenylephrine, and isoproterenol into the MnPO of sham MH-lesioned rats caused no change in the sodium intake induced by ANG II. ANG II injected into the MnPO of MH-lesioned rats increased sodium intake compared with sham-lesioned rats. Previous injection of clonidine and isoproterenol increased, whereas phenylephrine abolished the salt intake induced by ANG II into the MnPO of MH-lesioned rats. Previous injection of norepinephrine and clonidine into the MnPO of sham MH-lesioned rats caused no change in the mean arterial pressure (MAP) induced by ANG II. Under the same conditions, previous injection of phenylephrine increased, whereas isoproterenol reversed the increase in MAP induced by angiotensin II (ANG II). ANG II injected into the MnPO of MH-lesioned rats induce a decrease in MAP compared with sham-lesioned rats. Previous injection of phenylephrine or norepinephrine into the MnPO of MH-lesioned rats induced a negative MAP, whereas pretreatment with clonidine or isoproterenol increased the MAP produced by ANG II injected into the MnPO of sham- or MH-lesioned rats. These data show that ibotenic acid lesion of the MH increases the sodium intake and pressor responses induced by the concomitant angiotensinergic, alpha 2 and beta adrenergic activation of the MnPO, whereas alpha 1 activation may have opposite effects. MH involvement in excitatory and inhibitory mechanisms related to sodium intake and MAP control is suggested.