Functional consequences of enhanced expression of STIM1 and Orai1 in Huh-7 hepatocellular carcinoma tumor-initiating cells

Background

The endoplasmic reticulum (ER) Ca²⁺ sensor, stromal interaction molecule1 (STIM1) activates the plasma membrane (PM) channel Orai1 in order to mediate store-operated Ca²⁺ entry (SOCE) in response to ER store depletion. Enhanced expression of STIM1 in cancer tissue has been associated with poor patient prognosis. Therefore, this study investigated the functional consequences of enhanced expression of STIM1 and Orai1 in a tumor-initiating subpopulation of Huh-7 hepatocellular carcinoma (HCC) cells that express epithelial cell adhesion molecule (EpCAM) and Prominin 1 (CD133).

Methods

We performed qRT-PCR, intracellular Ca²⁺ monitoring, protein analyses, and real-time cell proliferation assays on EpCAM(+)CD133(+) subpopulation of tumor-initiating Huh-7 HCC cells expressing high levels of STIM1 and/or Orai1. Statistical significance between the means of two groups was evaluated using unpaired Student’s t-test.

Results

Enhanced STIM1 expression significantly increased ER Ca²⁺ release and proliferation rate of EpCAM(+)CD133(+) cells.

Conclusion

STIM1 overexpression may facilitate cancer cell survival by increasing ER Ca²⁺-buffering capacity, which makes more Ca²⁺ available for the cytosolic events, on the other hand, possibly preventing Ca²⁺-dependent enzymatic activity in mitochondria whose Ca²⁺ uniporter requires much higher cytosolic Ca²⁺ levels.

Serum amyloid A and Omentin levels in acute appendicitis: a preliminary study for a novel diagnostic approach

BACKGROUND

The diagnosis of acute appendicitis is based on medical history and physical examination. Serum (S) amiloid A (AA) levels are elevated in many inflammatory conditions. Omentin is a recently discovered adipokine showing decreased levels associated with inflammatory conditions. We aimed to measure SAA and omentin levels in patients with acute appendicitis.

MATERIALS AND METHODS

36 patients with a diagnosis of acute appendicitis and 30 healthy subjects were enrolled to this research study. A statistical analysis was performed using IBM SPSS Statistics Version 16.0 (SPSS Inc.®, Chicago, IL, United States).

RESULTS

Patients in study group were significantly older than healthy control subjects (p=0.013). Body mass index of the patients with acute appendicitis (23.2 ± 1.3) was greater than that of the control group (22.7 ± 1), but the difference did not reach the statistically significance (p=0.076). ). Mean level of SAA was significantly raised in study group compared to healthy control subjects (p< 0.001). Mean omentin level was significantly lower in study group compared to healthy subjects (p=0.013).

CONCLUSIONS

In conclusion, although diagnosis of acute appendicitis is mostly based on clinical findings, omentin and especially SAA measurement in serum may help surgeons to avoid negative laparatomy.

Effects of MMP-1 and MMP-3 gene polymorphisms on gene expression and protein level in lumbar disc herniation

The aim of this study was to identify the possible correlation between polymorphisms in matrix metalloproteinase (MMP)-1 and MMP-3 and their corresponding protein levels in disc tissues obtained from patients with lumbar disc herniation (LDH) using biochemical and immunohistochemical analyses. Blood and disc samples were obtained from 100 patients with LDH who underwent a lumbar microdiscectomy. Based on the radiological degeneration, the patients were diagnosed with grade 2, 3, or 4 LDH. MMP-1 -1607 1G/2G and MMP-3 -1171 5A/6A were analyzed by real-time polymerase chain reaction. The expressions of MMP-1 and MMP- 3 were detected by biochemical and immunohistochemical analyses. We found no association between the MMP-1 polymorphism and disc degeneration and MMP-1 expression. However, patients expressing the 6A/6A and 5A/6A alleles of MMP-3 -11715A/6A showed higher MMP-3 expression, compared to those expressing the 5A/5A genotype. Additionally, the radiological degeneration grades were correlated with the histological degeneration scoring. Protein levels and immunopositive cell rates of MMP-1 and MMP-3 were associated with disc degeneration grades. Moreover, the MMP-1 and MMP-3 expression and the histological and radiological scores were positively correlated and the MMP-3 -11715A/6A polymorphism was associated with MMP-3 expression in herniated disc tissues. This study is the first to investigate polymorphisms in MMP-1 and MMP-3, as well as their corresponding protein expressions. We also quantified an association between the radiological degeneration grades and MMP-1 and MMP- 3 expression. Further genomic studies on MMPs could focus on the utilization of MMP-1 and MMP-3 as markers for the prevention and treatment of this disease.

Alterations of store-operated calcium entry and cyclopiazonic acid-induced endothelium-derived relaxations in aging rat thoracic aorta

The purpose of our study was to investigate whether endothelium-derived relaxations induced by store depletion are altered in aging rat thoracic aorta. Vascular responses were measured in aortic segments isolated from young (2-4 month) and old (20-24 month) male Sprague-Dawley rats. In phenylephrine-contracted intact tissues, receptor-mediated and receptor-independent endothelium-derived relaxations were induced by acetylcholine (ACh) and sarcoplasmic/endoplasmic reticulum Ca²⁺ ATPase (SERCA) blocker cyclopiazonic acid (CPA), respectively. In addition, CPA-induced changes in intracellular calcium levels were monitored in fura-2-loaded endothelium-denuded tissues. Real-time quantitative reverse transcription polymerase chain reaction and western blot analysis were performed to determine the transient receptor potential canonical (TRPC) 4 mRNA and protein levels. Endothelial TRPC4 mRNA levels were apparently decreased in aging rats. Immunoblot analysis showed that TRPC4 protein levels significantly decreased in intact aorta from 20- to 24-month-old rats compared to that from 2- to 4-month-old rats. ACh- and CPA-induced endothelium-dependent relaxations decreased in old rat aorta without any change in direct vasodilation induced by sodium nitroprusside. Store-operated Ca²⁺ entry (SOCE) induced by CPA was significantly decreased, whereas sarcoplasmic reticulum Ca²⁺ release was unaffected in endothelium-denuded aging rat aorta. In conclusion, TRPC4 downregulation could be associated with decreased endothelium-dependent vasorelaxations. As endothelial nitric oxide synthase is activated by SOCE-induced caveolar internalization, tracking the expression levels of SERCA, ion channels, and/or associated proteins involved in SOCE would lead to the development of novel therapeutics for age-related vasospastic disorders with dysfunctional endothelium.

Effects of the inflammatory response on serum omentin levels in early acute and chronic pancreatitis

BACKGROUND AND AIMS

Acute pancreatitis is an acute inflammation of the parenchyma of the pancreas. Several adipokines have been investigated in acute pancreatitis, and these cytokines contribute to inflammation in acute pancreatitis. However, not enough data exist regarding omentin in injuries of the pancreas. Because of a possible common pathogenesis, we aimed to study the association between pancreatic damage and serum omentin levels.

MATERIALS AND METHODS

Twenty-four Sprague Dowley rats weighing 200-250 g were randomly placed into three groups: a sham group (n=8), an acute pancreatitis group (n=8), and a chronic pancreatitis group (n=8). Both rats in the sham group underwent laparotomy, and 0.1 cc of saline solution was injected through the pancreatic canal. On the seventh day, a blood sample was obtained by abdominal aorta puncture, and the pancreas was resected for histological examination. In the acute and chronic pancreatitis groups, 0.1 cc of 4.5% Sodium Taurocholote was injected through the pancreatic canal. Blood samples were obtained and pancreatic resection was performed after 24 hours for the acute pancreatitis group and after 7 days for the chronic pancreatitis group.

RESULTS

Serum omentin levels of rats with chronic pancreatitis (49.37±2.82 ng/ml) were increased compared to both acute pancreatitis (37.79±1.24 ng/ml) (p<0.01) and sham rats (22.49±1.4 ng/ml) (p<0.01). In addition, the omentin level of rats with acute pancreatitis was significantly increased compared to the sham group (p<0.01).

CONCLUSIONS

The elevation in omentin levels in rats in the early stage of pancreatitis was due to the anti-inflammatory effects of omentin; hence, elevated omentin levels improved insulin resistance and caused a significant reduction in glucose levels.

The protective effects of dexmedetomidine on hepatic ischemia reperfusion injury

OBJECTIVE

The aim of this study was to evaluate the effect of dexmedetomidine (100 µg/kg-ip) on liver ischemia and reperfusion (I/R) in rats.

METHODS

Twenty-four Wistar Albino rats were separated into three groups as control (C), ischemia-reperfusion injury (I/R) and dexmedetomidine group (I/R-D). Ischemia was induced with portal clampage for 45 minutes and reperfusion period was 45 minutes after declampage. Group I/R-D was received dexmedetomidine 100 µg/kg i.p. 30 min before portal clampage. Thiobarbutiric Acid-Reactive Substances (TBARS), glutathioneS-transferase (GST), superoxide dismutase (SOD), Catalase (CAT), and Paraoxonase 1 (PON-1) were investigated in blood samples. Also HSP60 and p53-positive hepatocytes were counted under ImageJ image analysis program.

RESULTS

All parameters, except GST levels, were significant between the groups (p < 0.05). Although HSP60 expression was significantly increased between I/R, I/R-D and C groups there were no significant differences between I/R-D and C (p = 0.443). On the other hand, p53 expression was also significantly increased between I/R, I/R-D and C groups At the same time, there were no significant differences between I/R-D and C groups (p = 0.354).

CONCLUSION

All the results suggest that dexmedetomidine has beneficial effects on liver ischemia/reperfusion stress (Tab. 1, Fig. 2, Ref. 49).

Serum omentin levels predicts mesenteric ischemia

BACKGROUND

Acute mesenteric ischemia (AMI) is an intestinal vascular disease with high mortality. Clinical diagnosis of acute mesenteric ischemia is difficult. Adipose tissue is an important mediator of metabolism and inflammation.Omentin is produced by visceral adipose tissue and decreased serum levels of omentin are associated with poor metabolic outcomes. We aimed to investigate whether serum omentin level predicts early diagnosis of AMI before development of transmural ischemia.

METHODS

Twenty-four Sprague Dawley rats weighted about 200-250 gr grouped in 3 experimental groups as sham, transient ischemia and permanent ischemia. Each group consisted of 8 rats. Blood samples were evaluated to determine serum urea, creatinine, omentin and C-reactive protein (CRP) levels. A blinded histological examination performed with the same histologist for hemotoxileneosine painted ileal tissue samples.

RESULTS

Mean serum omentin level in sham group (27.5±4.67) was significantly elevated compared to rats in Ischemia-reperfusion (IR) group (10.9±9.01).The difference reached the statistical significance (p=0.004). Serum omentin levels were not correlated to urea, creatinine or CRPlevels.

CONCLUSION

Omentin levels may be a biochemical indicator to detect AMI. However, further human studies are needed (Tab. 3, Fig. 3, Ref. 34).

Hepatocyte apoptotic index and p53 expression in obstructive jaundice rats

OBJECTIVE

Obstructive jaundice is a serious disease. It can deteriorate critical functions in the liver.

MATERIAL AND METHOD

A total of 20 male Wistar-Albino rats were randomly allocated into two groups consisting of ten in each as follows: Group I (Control) was subjected to a sham operation isolating the bile duct. Group II(Study) was subjected to acute cholestasis induced by bile duct ligation with 4/0 silk suture from two different places and full fold cut between ligatures. On the 7th day, group II rats were re-operated for liver sampling and sacrification-aimed histological analysis through the old incision with anaesthesia. Hepatic tissues were histologically and immunohistochemically processed. The number of apoptotic and p53(+) cells were measured.

RESULTS

On the 7th day, the averages of direct and indirect bilirubin values in Group II rats were found to be 6.99 and 11.70 mg/dl, respectively. They were observed to be statistically significant. In the immunohistochemical evaluation p53 expression in hepatocytes was assessed, p53-positive hepatocytes were determined to exist quite widely in the tissue samples taken from the livers of rats in the study group. Nevertheless, no cells exhibiting p53 expression were found in the tissue samples of the control group.

CONCLUSION

Apoptosis is a closed box and it might make it possible to stop the many disease processes or accelerate the healing. If the principal effective mechanism in the liver under a certain stress factor is apoptosis, it is definite that it will make a difference in the treatment approach. Consequently, we can say that both apoptotic index and p53 expression increase in the rats' liver with biliary obstruction (Fig. 4, Ref. 51).

Clinical analysis of emergency peripartum hysterectomies in a tertiary center

OBJECTIVE

To investigate the incidence, indications, complications, and risk factors associated with increased mortality and morbidity of emergency peripartum hysterectomy (EPH).

MATERIALS AND METHODS

The authors retrospectively analyzed 48 cases of EPH performed within six-year interval at Ondokuz Mayis University Hospital. EPH was defined as the operation performed for life-threatening hemorrhage which could not be controlled with conservative treatment modalities within 24 hours of a delivery.

RESULTS

The incidence of EPH was 5.03 per 1,000 deliveries. The most common indication for EPH was abnormal placental adherence (n = 22, 45.8%), followed by uter- ine atony (n = 19, 39.6%). All the patients with placenta accreta had a history of repeat cesarian section (CS) and placenta previa.Total hysterectomy was performed in almost all of the patients (n = 47, 97.9%). All women required blood transfusions. Maternal morbidity was significant, with bladder injury (31.3%) and disseminated intravascular coagulation (18.7%) among the most common complications. There were one maternal (2.1%) and five neonatal deaths (10.4%).

CONCLUSION

Since most of the EPH cases are associated with prior cesarean delivery, decision of the first CS should be made for true obstetrical indications.If conservative treatments fail to control massive obstetrical bleeding, blood products and an experienced obstetrician should be ready to perform EPH to decrease the maternal mor- bidity and mortality.

Detecting the translocation of DNA through a nanopore using graphene nanoribbons

Solid-state nanopores can act as single-molecule sensors and could potentially be used to rapidly sequence DNA molecules. However, nanopores are typically fabricated in insulating membranes that are as thick as 15 bases, which makes it difficult for the devices to read individual bases. Graphene is only 0.335 nm thick (equivalent to the spacing between two bases in a DNA chain) and could therefore provide a suitable membrane for sequencing applications. Here, we show that a solid-state nanopore can be integrated with a graphene nanoribbon transistor to create a sensor for DNA translocation. As DNA molecules move through the pore, the device can simultaneously measure drops in ionic current and changes in local voltage in the transistor, which can both be used to detect the molecules. We examine the correlation between these two signals and use the ionic current measurements as a real-time control of the graphene-based sensing device.

Protective effect of montelukast, a cysteinyl leukotriene receptor-1 antagonist, against intestinal ischemia-reperfusion injury in the rat

OBJECTIVE

Ischemia-reperfusion (I-R) injury of the intestine is a significant problem because the initial damage caused by ischemia is exacerbated by reperfusion. In this study, we examined the protective effect of montelukast against I-R-induced intestinal tissue damage.

MATERIALS AND METHODS

Eight-week-old male Sprague-Dawley rats were randomly divided into three treatment groups : a sham-operated group, a group receiving I-R, and a group receiving I-R plus montelukast (I-R/M). Tissue samples were evaluated and scored histologically. The blood levels of malondialdehyde (MDA), myeloperoxidase (MPO), glutathione (GSH), and cardiotrophin-1 (CT-1) were measured.

RESULTS

In the I-R group, the histological score and the levels of serum MDA and MPO were increased compared with those in the control group. In the I-R/M group, the histological score and serum MDA and MPO levels were significantly decreased compared with those in the I-R group. Additionally, compared with the IR group, the I-R/M group had increased serum GSH and CT-1 levels and a decreased intestinal injury score. Ileal sections from the I-R/M group showed minimal alterations, characterized by moderate lifting of the epithelial layer from the lamina propria, and few apoptotic enterocytes were observed compare with the number in the I-R group.

CONCLUSION

The findings of the present study demonstrated that montelukast can protect I-R-induced intestinal damage in rats.

Platelet function in euthyroid patients undergoing thyroidectomy in women

BACKGROUND

Several studies have reported several platelet abnormalities in patients with sub-clinical or overt thyroid dysfunctions. The primary mechanism that affects the hemostatic balance is excess or deficiency of thyroid hormones. The different ways of thyroid gland to the platelet function are not yet clearly understood. The relationship between in the thyroid gland and platelet activation without thyroid hormones has not been studied yet.

AIM

The aim of our study is to determine the platelet function in euthyroid patients undergoing thyroidectomy in females.

PATIENTS AND METHODS

The study group includes 52 female euthyroid patients undergoing thyroidectomy. The control group consisted with 21 healthy euthyroid female. Platelet count (PC), platelet mass (PM), mean platelet volume (MPV), and platelet distribution width (PDW) were measured. PM was calculated by multiplying MPV and PLT.

RESULTS

MPV (8.4 ± 1.3 versus 7.9 ± 0.8) and PDW (17.8 ± 1 versus 17.6 ± 0.8) values were similar between the two groups.

CONCLUSIONS

Thyroid gland does not directly affect platelet activation. Accordingly, platelet abnormalities of thyroid disease can be considered to be independent of the underlying thyroid tissue. This finding suggests that association between thyroid diseases and platelet function is dependent on the status of thyroid hormones.

Lung tissue apoptosis in abdominal hypertension : Apoptosis and necrosis of lung tissue in abdominal hypertension

OBJECTIVES

The aim of this study was to evaluate lung tissue histopathologic changes and the number of apoptosis with the increase of abdominal pressure.

METHODS

The study rats were randomly assigned into the following five groups: a sham operated group and groups 1, 2, 3 and 4, in which the intra-abdominal pressure was increased to 11, 15, 18 and 22 mmHg for 60 min, respectively. Lungs were harvested for histopathologic changes and the tissue apoptotic analysis were carried out in a blinded manner.

RESULTS

All of the data showed that the number of apoptotic cells and necrosis were increased in accordance with the pressure level. However, this increase was statistically significant, especially in groups 3 and 4 (18 and 22 mmHg, respectively; p < 0.05) when compared to the sham operated rats. There were no differences observed between groups 1 and 2 (11 and 15 mmHg, respectively) and the sham operated rats. There was also no difference between groups 1 and 2. There were findings of coagulation necrosis and the number of apoptotic cells linearly increased when the abdominal pressure was increased. The cut-off value was 15 mmHg.

CONCLUSION

The available findings suggest that intra-abdominal pressure greater than 15 mmHg could irreversibly damage pulmonary cells and both coagulation necrosis parameters and the number of apoptosis increase in accordance with the pressure level.

Primary carcinoma of the neovagina: a case report

We present a case of squamous cell carcinoma arising in the neovagina of a woman in whom we performed vaginoplasty 20 years before. To the best of our knowledge, this is the 23rd case of total carcinoma arising in the neovagina constructed because of vaginal agenesis, and the 3nd case of carcinoma arising in the neovagina performed without using a graft.

Clinical and molecular studies in two families with Fraser syndrome: a new FRAS1 gene mutation, prenatal ultrasound findings and implications for genetic counselling

Fraser syndrome is a rare autosomal recessive genetic disorder characterized by cryptophthalmus, variable expression of cutaneous syndactyly of fingers and toes, genital ambiguity and renal agenesis/dysgenesis. We present here molecular and clinical findings of four fetuses with FS from two families. Molecular genetic studies in the two families revealed mutations in FRAS1 gene allowing better genetic counselling and subsequent prenatal diagnosis in one of the two families. In family one, a nonsense mutation (c.3730C>T, p.R1244X) previously described in a Polish patient was found. In family two a novel nonsense mutation previously not known was detected (c.370C>T, p.R124X). PGD is planned for family 1.

Characterization of red raspberry (Rubus idaeus L.) genotypes for their physicochemical properties

The worldwide tendency for growing more small fruits, including raspberries, shows permanent increase because this group of fruits has a relatively higher content of bioactive nutrients. To study the health benefits of red raspberry fruits, 11 preselected wild-grown and 1 well-known cultivar, Heritage, were evaluated for some of their physicochemical properties such as fruit weight, total antioxidant capacity (measured by beta-carotene bleaching and FRAP assays), total phenolics, ascorbic acid, soluble solid content (SSC), and acidity. Fruit weight, SSC, and ascorbic acid contents were between 1.47 and 2.32 g, 10.87% and 13.60%, and 21 and 36 mg/100 g, respectively. Antioxidant activity and total phenolic content varied among genotypes and the ERZ5 genotype had the highest antioxidant capacity as ascertained by both methods. This genotype also had the highest total phenolic (2031 microg GAE/g FW) content. There are linear relationships between antioxidant capacities and total phenols. The present study demonstrates the potential of certain wild genotypes, notably ERZ5, for improving the nutritional value through germplasm enhancement programs.

Age-related diseases; degenerative aortic valve disease and osteoarthritis

OBJECTIVE

To examine the relationship between degenerative aortic valve disease and osteoarthritis Background: Degenerative aortic valve disease (DAVD) and osteoarthritis (OA) are age-related degenerative diseases whose pathogenesis involves mechanical stress and local inflammation.

METHODS

Forty-four patients with DAVD (Group 1) and 21 controls (Group 2) were included in this study, which was intended to investigate the similarity between the two conditions. The two groups were similar in terms of age, sex, body mass index, a history of hypertension, cholesterol levels, diabetes mellitus and cigarette consumption.

RESULTS

The average age + standard deviation of the DAVD patients were 71.3 +/- 7.5, compared to 67.5 +/- 10.6 in the control group. In radiological OA analysis, the Lane scale was employed in the lumbar region and the Kellgren-Lawrence scale in the knee joint. Comparison of Groups 1 and 2 revealed no difference in radiological OA in the lumbar region and knee joint.

CONCLUSION

Our study has shown that there is no relationship between these diseases that increased with age. However, extensive studies examining pathogenic mechanisms are needed (Tab. 2, Ref. 11).

Protective effects of doxycycline in ischemia/reperfusion injury on kidney

Renal ischemia and reperfusion injury is the major cause of acute renal failure and may also be involved in the development and progression of some forms of chronic kidney disease. The aim of this study was to evaluate whether doxycycline, a member of the tetracycline family of antibiotics, protects kidney tissue or not. 36 Sprague-Dawley rats (200-250 g) were used. The animals were divided into three groups: control, ischemia/reperfusion and ischemia/reperfusion+doxycycline group. Rats were subjected to renal ischemia by clamping the left pedicle for 1 h, and then reperfused for 1 h. The ischemia/reperfusion+doxycycline group were pretreated intraperitoneally with doxycycline suspension (10 mg/kg) 2 h before the induction of ischemia. Our results indicate that malondialdehyde, matrix-metalloproteinase-2, interleukin-2, interleukin-6, interleukin-10, interleukin 1-beta and tumor necrosis factor-alpha levels were significantly higher in the ischemia/reperfusion group than those in the control group. Doxycycline administration significantly decreased these parameters. Tissue inhibitor of metalloproteinases-1 levels also increased after ischemia/reperfusion and decreased with doxycycline pretreatment, but these changes were not significantly different. Glutathione levels significantly decreased after ischemia/reperfusion injury when compared with the control group and doxycycline pretreatment significantly increased glutathione levels when compared with the ischemia/reperfusion group. Apoptotic cells and p53 positive cells were significantly decreased in doxycycline treated group. These results suggest that doxycycline reduces renal oxidative injury and facilitates repair. Doxycycline may play a role in a renoprotective therapeutic regimen.

Efficacy of levamisole on experimental endometriosis

OBJECTIVE

To investigate the efficacy of levamisole on experimental endometriosis.

METHODS

After the implantation of endometrial tissue on abdominal peritoneum, 40 rats were randomized to 1 of 4 equal intervention groups. Levamisole (2 mg/rat) was applied subcutaneously to group "L" once a week. Depot medroxyprogesterone acetate (3 mg/kg) was applied intramuscularly to group "M" twice at 4-week intervals. Leuprolide (0.075 mg/kg) was applied subcutaneously to group "G" twice at 4-week intervals. Saline (0.1 cm(3)/rat) was applied subcutaneously to group "C" once a week for 8 weeks. The efficacy of levamisole was determined by volume measurement and characterizing the histological structure of the implants.

RESULT

Volume increase of the implants in group C (P<0.05), and volume decrease in groups M, G, and L was found (P<0.05, P<0.01, and P<0.01, respectively.) Stromal tissue and glandular activity were not different between groups L and G.

CONCLUSION

Levamisole was found to be as effective as leuprolide in regression of the volume of endometriotic implants.

Sarcoplasmic-endoplasmic reticulum Ca2+-ATPase inhibition prevents endothelin A receptor antagonism in rat aorta

This study tested whether sarcoplasmic-endoplasmic reticulum Ca(2+)-ATPase regulates the ability of endothelin receptor antagonist to inhibit the endothelin-1 constriction. The endothelin A receptor antagonist BQ-123 (1 microM) completely relaxed constriction to 10 nM endothelin-1 in endothelium-denuded rat aorta. Challenge with cyclopiazonic acid (10 microM), a sarcoplasmic-endoplasmic reticulum Ca(2+)-ATPase inhibitor, during the plateau of endothelin-1 constriction enhanced the constriction by approximately 30%. BQ-123 relaxed the endothelin-1 plus cyclopiazonic acid constriction by only approximately 10%. In contrast, prazosin (1 microM), an alpha-adrenergic receptor antagonist, still completely relaxed the 0.3 muM phenylephrine constriction in the presence of cyclopiazonic acid. Verapamil relaxed the endothelin-1 plus cyclopiazonic acid constriction by approximately 30%, whereas Ni(2+) and 2-aminoethoxydiphenyl borate, nonselective cation channel and store-operated channel blockers, respectively, completely relaxed the constriction. These results suggest that lowered sarcoplasmic-endoplasmic reticulum Ca(2+)-ATPase activity selectively decreases the ability of endothelin receptor antagonist to inhibit the endothelin A receptor. The decreased antagonism may be related to the opening of store-operated channels and subsequent greater internalization of endothelin A receptor.

Isokinetic muscle performance in major depressive disorder: alterations by antidepressant therapy

The aims of this study were (i) to examine whether patients with major depressive disorder (MDD) differ from healthy control subjects with respect to isokinetic muscle performance (IMP) as measured by a dynamometer; (ii) to investigate the effect of subchronic treatment on the IMP in depressed patients. Thirty-eight patients with MDD, and 41 sex- and age-matched healthy controls participated in this study. The severity of depression and anxiety levels were evaluated by the Hamilton Depression and Anxiety Scales. Quadriceps and hamstring IMPs were determined by using an isokinetic dynamometer before and after subchronic antidepressant treatment. The patients had lower IMP levels than healthy controls. After treatment for three months with selective serotonin reuptake inhibitors, the IMP levels increased significantly. These findings suggest that (i) MDD may be characterized by reduced IMP levels; and (ii) treatment with antidepressants may increase the IMP levels, as a state marker for depression. It was concluded that (i) isokinetic muscle performance may be used as a state marker for monitoring antidepressant drug effects on MDD; (ii) isokinetic exercise increasing IMP may be used in the treatment of depression.

Isokinetic muscle performance in major depressive disorder: alterations by antidepressant therapy

The aims of this study were (i) to examine whether patients with major depressive disorder (MDD) differ from healthy control subjects with respect to isokinetic muscle performance (IMP) as measured by a dynamometer; (ii) to investigate the effect of subchronic treatment on the IMP in depressed patients. Thirty-eight patients with MDD, and 41 sex- and age-matched healthy controls participated in this study. The severity of depression and anxiety levels was evaluated by the Hamilton Depression and Anxiety Scales. Quadriceps and hamstring IMPs were determined by using an isokinetic dynamometer before and after subchronic antidepressant treatment. The patients had lower IMP levels than healthy controls. After treatment for three months with selective serotonin reuptake inhibitors, the IMP levels increased significantly. These findings suggest that (i) MDD may be characterized by reduced IMP levels; and (ii) treatment with antidepressants may increase the IMP levels, being a state marker for depression. It was concluded that (i) isokinetic muscle performance may be used as a state marker for monitoring antidepressant drug effects on MDD; (ii) isokinetic exercise increasing IMP may be used in the treatment of depression.

Effects of nicardipine on collar-induced intimal thickening and vascular reactivity in the rabbit

The effects of nicardipine treatment on collar-induced intimal thickening and on accompanying reactivity changes in rabbit carotid artery have been investigated. Treatment for three weeks with subcutaneous nicardipine (20 mgkg(-1) per day) significantly inhibited the intimal thickening caused by perivascular application of a silicone rubber collar. Potassium chloride (KCl), phenylephrine and 5-hydroxytryptamine (5-HT) induced concentration-dependent contractions in both sham-operated and collared arteries. Collar-induced attenuation of maximum KCl-, phenylephrine- and 5-HT-induced contraction was not affected by nicardipine. Collaring caused the means of pD2 values (the negative logarithm of EC50 values, 50% effective concentration) of 5-HT and phenylephrine to increase and decrease, respectively. Nicardipine did not affect the altered sensitivity to these agonists. Neither collar implantation nor nicardipine treatment altered the pD2 values for acetylcholine- and nitroglycerine-induced relaxations. These results demonstrate that nicardipine inhibits collar-induced intimal thickening in rabbit carotid artery without affecting the accompanying changes in vascular reactivity, indicating a possible lack of association between the development of intimal thickening and altered reactivity.

Coupling of store-operated Ca++ entry to contraction in rat aorta

The purpose of this study was to test whether the elevated intracellular Ca++ level ([Ca++]i) resulting from store-operated Ca++ entry was associated with vascular smooth muscle contraction. Cyclopiazonic acid (CPA), a selective inhibitor of sarcoplasmic reticulum Ca(++)-ATPase, concentration-dependently (1-10 microM) elevated [Ca++]i in rat aorta, as indicated by an increase in the fura-2 340/380 ratio. Simultaneous measurement of contraction demonstrated that 1 and 10 microM CPA induced insignificant and variable amounts of contraction, respectively. Verapamil (10 microM) had relatively little effect on the 1 and 10 microM CPA-elevated [Ca++]i. In contrast, Ni++ (0.1 mM), in the presence of verapamil, abolished the 1 microM CPA-elevated [Ca++]i. Ni++ (0.1 mM) also partially decreased the 10 microM CPA-elevated [Ca++]i and, furthermore, abolished the associated contraction. A higher Ni++ concentration (1 mM) abolished the 10 microM CPA-elevated [Ca++]i that remained after verapamil and 0.1 mM Ni++. Phorbol dibutyrate (10 nM), a protein kinase C activator, potentiated contractions to 1 and 10 microM CPA in the presence of verapamil. Ni++ (0.1 mM) abolished the enhanced contractions, and decreased the elevated [Ca++]i. These results suggest that 1) elevated [Ca++]i due to store-operated Ca++ entry is dissociated from contraction; 2) the elevated [Ca++]i is restricted to at least two noncontractile compartments that can be differentiated by their relative sensitivities to blockade by low (0.1 mM) and higher (1 mM) Ni++ concentrations, and 3) [Ca++]i elevation within the compartment sensitive to blockade by 0.1 mM Ni++ can be coupled to contraction via protein kinase C activation.

Role of extracellular Ca++ influx via L-type and non-L-type Ca++ channels in thromboxane A2 receptor-mediated contraction in rat aorta

The purpose of this study was to investigate the role of extracellular Ca++ influx via L-type and non-L-type Ca++ channels in thromboxane A2 receptor-mediated contraction. In intact rat aorta, U46619, a selective thromboxane A2 receptor agonist, induced concentration-dependent increases in intracellular Ca++ ([Ca++]i) and contraction (EC50 values of 5.5 and 6.1 nM, respectively). U46619 (10 nM) induced approximately 60 to 70% of maximal [Ca++]i elevation and contraction. Treatment with verapamil, an L-type Ca++ channel blocker, before 10 nM U46619 challenge, or during the plateau [Ca++]i elevation and contraction, decreased these parameters by approximately 50%. Ni++, a nonselective blocker of cation channels, or SKF96365, a purported blocker of receptor-operated Ca++ channels, further decreased the contraction and abolished the [Ca++]i elevation that remained after verapamil treatment of 10 nM U46619-challenged vessels. Pretreatment with verapamil and Ni++ to prevent Ca++ influx and with cyclopiazonic acid to deplete [Ca++]i stores also partially prevented U46619-induced contraction, whereas [Ca++]i elevation was abolished. These results suggest that thromboxane A2 receptor-mediated contraction of vascular smooth muscle partly depends on the influx of extracellular Ca++ via both L-type and non-L-type Ca++ channels, as well as a mechanism independent of [Ca++]i elevation.

Intracellular Ca2+ elevation and contraction due to prostaglandin F2alpha in rat aorta

Prostaglandin F2alpha was tested to determine (a) whether its effect on intracellular Ca2+ levels ([Ca2+]i) and force in vascular smooth muscle was mediated through activation of the thromboxane A2 and/or prostaglandin receptor, and (b) the relative roles of Ca2+ influx via L-type and non-L-type Ca2+ channels in prostaglandin receptor-mediated contraction. [Ca2+]i and force were measured simultaneously in fura-2-loaded rat aortic strips. The thromboxane A2 receptor antagonist, SQ29548 ([1S]-1a,2b(5Z),3b,4a-7-(3-[2-[(phenylamino)carbonyl] hydrazinomethyl)-7-oxobicyclo-[2.2.1]hept-2-yl-5-heptenoic acid), prevented the prostaglandin F2alpha-induced plateau [Ca2+]i elevation and force by 80-90%, while abolishing these responses due to the thromboxane A2 receptor agonist, U46619 (9,11-dideoxy-9alpha,11alpha-methanoepoxy prostaglandin F2alpha). Prostaglandin F2alpha (+ SQ29548)-induced plateau [Ca2+]i elevation and force were not inhibited by verapamil. Ni2+, a non-selective cation channel blocker, in the presence of verapamil, abolished the prostaglandin F2alpha (+ SQ29548)-elevated [Ca2+]i, while the contraction was only partially inhibited. These results suggest that, in rat aorta, (1) elevated [Ca2+]i and force due to high prostaglandin F2alpha concentrations largely results from thromboxane A2 receptor activation, and (2) the prostaglandin component of the prostaglandin F2alpha-induced contraction is dependent on Ca2+ influx via non-L-type channels.

Plasma endothelin-1 levels in Behçet's disease

Plasma concentrations of endothelin-1 (ET-1), a vasoconstrictor peptide released from vascular endothelial and synovial cells, were measured by radioimmunoassay in 27 patients with Behçet's disease (BD) and 18 healthy controls. The plasma ET-1 concentrations were found to be significantly increased in patients with BD (121.15 +/- 11.6 fmol/dl) compared with the healthy subjects (89.37 +/- 8.03 fmol/dl p < 0.05). The elevation of ET-1 did not correlate with the disease duration, gender, ocular or articular involvement. Whether the elevated ET-1 level is a direct result of its increased synthesis from injured vascular endothelial cells or whether its presence in high concentrations may be responsible, together with other factors for both vascular and articular complications in patients with BD is uncertain.

Role of extracellular Ca2+ in subarachnoid hemorrhage-induced spasm of the rabbit basilar artery

BACKGROUND AND PURPOSE

The role of extracellular Ca2+ in the maintenance of chronic vasospasm after subarachnoid hemorrhage (SAH) is largely unknown. Indeed, studies thus far have been limited to demonstrations that L-type Ca(2+)-channel antagonists were unable to reverse the spasm. This study tested whether SAH-induced vasospasm is maintained, at least in part. through the influx of extracellular Ca2+ and whether the influx of extracellular Ca2+ occurs through L-type Ca2+ channels and possibly, in addition, through store operated channels (SOCs). Furthermore, as there is considerable evidence in the literature to suggest that the spasm is mediated through endothelin-1 (ET-1) release, we tested whether the Ca2+ dependency of the spasm was consistent with the mediation of the spasm by ET-1.

METHODS

Chronic spasm of the basilar artery was induced in a double SAH rabbit model. Relaxation of SAH-, ET-1-, serotonin-, and KC1-constricted basilar artery in response to Ca(2+)-free solution, verapamil, and Ni2+ was measured in situ with the use of a cranial window.

RESULTS

SAH induced 23% constriction of the basilar artery. Ca(2+)-free solution and 1 mumol/L verapamil reversed the constriction of SAH vessels by 60% and 17%, respectively. In contrast, control vessels challenged with 40 to 50 mmol/L KCl, which induced 34% constriction, relaxed in response to Ca(2+)-free solution and verapamil by 98% and 89%, respectively. In SAH vessels, verapamil followed by 0.1 mmol/L Ni2+, which is known to block SOCs, induced a combined relaxation of 67%. Control vessels challenged with 3 nmol/L ET-1, which induced a magnitude of constriction similar to that of SAH (29%), relaxed in response to Ca(2+)-free solution, verapamil, and verapamil plus Ni2+ by 69%, 20%, and 50%, respectively (P > .05) versus respective values in SAH vessels). In contrast, control vessels challenged with 2 to 8 mumol/L serotonin, which induced a magnitude of constriction similar to those of SAH and ET-1 (22%), completely relaxed in response to Ca(2+)-free solution and verapamil.

CONCLUSIONS

These results demonstrate that the maintenance of chronic spasm in the two-hemorrhage rabbit model after SAH is due to smooth muscle cell contractile mechanisms partly dependent on the influx of extracellular Ca2+. The influx of extracellular Ca2+ results from the opening of L-type Ca2+ channels and an additional channel or channels. We speculate that the L-type Ca2+ channel-independent influx of extracellular Ca2+ results from the opening of SOCs. The Ca(2+)-dependent characteristics of the spasm likely reflect the mediation of the spasm by ET-1.

Doppler evaluation of left ventricular diastolic filling in Behçet's disease

Although cardiac involvement such as pericarditis, myocarditis, coronary arteritis and valvular disease in Behçet's disease occurs, few studies have assessed left ventricular diastolic function. This study assesses the prevalence of both systolic and diastolic left ventricular dysfunction in patients with Behçet's disease who have no clinical cardiac manifestations. Twenty-two patients (12 women and 10 men, mean age 34 +/- 2.4 years) underwent full clinical examination, electrocardiography, M-mode, two-dimensional, and Doppler echocardiography. The mean disease duration was 5 +/- 4.7 years (range, 1 month-16 years). As age and sex-matched control group of 20 healthy subjects was also studied. Prolonged isovolumic relaxation time, prolonged deceleration time, reversal of the early and late peak transmitral diastolic flow velocities, late peak transmitral diastolic flow velocities (E/A ratio) and increased atrial filling fraction were noted in five patients. It is concluded that left ventricular dysfunction occurs frequently in patients with Behçet's disease and Doppler echocardiography may be valuable in detecting diastolic filling abnormalities as an early sign of cardiac involvement.