Lifestyle and cardiovascular risk factors in a Swedish primary care population with self-reported psychiatric symptoms.

Objective: Individuals with psychiatric illness suffer from poorer physical health compared with the general population and have a higher risk of developing cardiovascular and metabolic diseases. This cross-sectional study aims to describe the prevalence of lifestyle and cardiovascular risk factors and the association with self-reported psychiatric symptoms in a population of 40-year-old individuals screened with targeted Health Dialogues in southern Sweden. Methods: All 40-year-old individuals registered at 99 primary healthcare centers in southern Sweden were invited to participate. Self-reported lifestyle habits on a web questionnaire, anthropometric measurements, blood pressure, and blood tests were collected. The Health Dialogue resulted in a risk level assessment for different lifestyle habits and a meeting with a trained coach. Results: A total of 1831 individuals completed a Health Dialogue between 1st January 2021 and 30th June 2022. There were more individuals with high-risk levels for several lifestyle habits in the group with self-reported psychiatric illness compared with the rest of the study population. The analysis showed that physical inactivity, unhealthy diet, high-risk alcohol intake, tobacco use, psychosocial strain, higher BMI, and waist-hip ratio were associated with increased levels of psychiatric symptoms after adjustment for sex and socioeconomic factors. Conclusion: Unhealthy lifestyle habits were associated with self-reported psychiatric symptoms in 40-year-old individuals assessed with targeted Health Dialogues in a primary care context. Organized screening might contribute to early detection of modifiable risk factors for cardiovascular disease. Individuals with psychiatric symptoms should be prioritized for screening of unhealthy lifestyle behaviors.

Familial Segregation of Venous Thromboembolism in Sweden: A Nationwide Family Study of Heritability and Complex Segregation Analysis.

Background This is the first nationwide segregation analysis that aimed to determine whether familial venous thromboembolism (VTE) is attributable to inheritance and/or shared environment, and the possible mode of inheritance. Methods and Results The Swedish Multi-Generation Register was linked to the Swedish patient register for the period 1964 to 2015. Three generational families of Swedish-born individuals were identified. Heritability was examined using Falconer regression. Complex segregation analysis was conducted using the Statistical Analysis for Genetic Epidemiology software (version 6.4, 64-bit Linux). Among the 4 301 174 relatives from 450 558 pedigrees, 177 865 (52% women) individuals were affected with VTE. VTE occurred in 2 or more affected relatives in 61 217 (13.6%) of the pedigrees. Heritability showed age and sex dependence with higher heritability for men and young individuals. In 18 933 pedigrees, VTE occurred only in the first generation and was not inherited. Segregation analysis was performed in the remaining 42 284 pedigrees with inherited VTE and included 939 192 individuals. Prevalence constraints were imposed in the models to allow for the selection of the pedigrees analyzed. The sporadic nongenetic model could be discarded. The major-type-only model, with a correlation structure compatible with some polygenic effects, was the preferred model. Among the Mendelian models, the mixed codominant (plus polygenic) model was preferred. Conclusions This nationwide segregation analysis of VTE supports a genetic cause of the familial aggregation of VTE. Heritability was higher for men and younger individuals, suggesting a Carter effect, in agreement with a multifactorial threshold inheritance.

Diagnostic center for primary care patients with nonspecific symptoms and suspected cancer: compliance to workflow and accuracy of tests and examinations.

OBJECTIVE: To evaluate compliance to workflow and accuracy of tests in Sweden's first fast-track referral pathway for patients with nonspecific symptoms and suspected cancer (SCAN). DESIGN: Prospective cohort study with consecutive inclusion of patients referred to the diagnostic center (DC). SETTING: Patients with nonspecific symptoms were examined in primary care according to a protocol including two test packages and diagnostic imaging. If symptoms were not explained, patients were referred to the DC and a DC-test package was taken. At the DC, further investigations resulted in diagnosis/no diagnosis. SUBJECTS: A total of 290 patients, median age 69 years (interquartile range [IQR] 59-76), 48% men, participated. A total of 64 (22%) were diagnosed with cancer, 186 (64%) with non-malignant disease and 40 (14%) had no new disease. MAIN OUTCOME MEASURE: Compliance was estimated by percentage of compulsory tests taken. Test accuracy was assessed by likelihood ratios (LRs) regarding cancer. RESULTS: A total of 23 (8%) patients had taken both primary care packages, whereas 150 (52%) patients went through entire diagnostic imaging. Abnormal pulmonary X-ray, peak expiratory flow (PEF) and calcium had the highest LRs in primary care (3.5; 3.2; 2.7). A total of 105 (36%) took the complete DC-package, of which bilirubin and cytomegalovirus had the highest LRs (11.5; 10.9). The median number (IQR) of abnormal primary care tests was 5 (3-6) for cancer, 3 (2-6) for other diagnoses and 1 (0-3) for no diagnosis. CONCLUSIONS: Compliance to test packages in primary care was low, which warrants review of the workflow. Few single tests had high accuracy regarding cancer, but the number of abnormal tests can provide guidance in complicated investigations of suspected malignancies.KEY POINTSFast-track referral pathways for patients with nonspecific serious symptoms have been implemented in several countries and are part of the national cancer strategy in all of Scandinavia.Compliance with compulsory tests in primary care was modest in this study; 8% of the patients had taken the entire compulsory test packages.Few single compulsory tests had high accuracy regarding subsequent cancer, which warrants a review of tests and examinations. However, patients diagnosed with cancer had a higher number of abnormal test results compared to the other groups.

Effect of mindfulness on physical activity in primary healthcare patients: a randomised controlled trial pilot study.

Increased physical activity can have health benefits among inactive individuals. In Sweden, the healthcare system uses physical activity on prescription (PAP) to motivate patients to increase their physical activity level. Mindfulness may further heighten the internal motivation to engage in physical activity. However, previous research has not demonstrated clear evidence of such an association. AIM: Examine the feasibility of the study design as a preparation for a full-scale study, and examine the differences, between three interventions, in change over time in physical activity levels and in related variables. METHOD: Comparison between three different interventions in an ordinary primary health care setting: PAP, mindfulness, and a combination of PAP and mindfulness. Physical activity was measured with self-report and ACTi Graph GT1X activity monitor. Statistical analysis was performed with a mixed-effect model to account for repeated observations and estimate differences both within groups and between groups at 3- and 6-months follow-up. RESULTS: Between September 2016 and December 2018, a total of 88 participants were randomised into three groups. The total dropout rate was 20.4%, the attendance rate to the mindfulness courses (52% > 6 times) and the web-based mindfulness training (8% > 800 min) was low according to the stated feasibility criteria. Eleven participants were excluded from analysis due to low activity monitor wear time. Neither the activity monitor data nor self-reported physical activity showed any significant differences between the groups. CONCLUSION: The study design needs adjustment for the mindfulness intervention design before a fully scaled study can be conducted. A combination of PAP and mindfulness may increase physical activity and self-rated health more than PAP or mindfulness alone. TRIAL REGISTRATION: ClinicalTrials.gov, registration number NCT02869854 . Regional Ethical Review Board in Lund registration number 2016/404.

Time Intervals Under the Lens at Sweden's First Diagnostic Center for Primary Care Patients With Nonspecific Symptoms of Cancer. A Comparison With Matched Control Patients.

INTRODUCTION: Fast-track referral pathways for patients with nonspecific, serious symptoms have been implemented in several countries. Our objective was to analyze time intervals in the diagnostic routes of patients diagnosed with cancer at Sweden's first Diagnostic Center (DC) for nonspecific symptoms and compare with time intervals of matched control patients. METHODS: Adult patients with nonspecific symptoms that could not be explained by an initial investigation in primary care were eligible for referral to the DC. Patients diagnosed with cancer were matched with patients at another hospital within the same healthcare organization. We aimed for two control patients per DC-patient and matched on tumor type, age and sex. Five time intervals were compared: 1) patient interval (first symptom-primary care contact), 2) primary care interval (first visit-referral to the DC/secondary care), 3) diagnostic interval (first visit-cancer diagnosis), 4) information interval (cancer diagnosis-patient informed) and 5) treatment interval (cancer diagnosis-treatment start). Comparisons between groups and matched cohort analyses were made. RESULTS: Sixty-four patients (22.1%) were diagnosed with cancer at the DC, of which eight were not matchable. Forty-two patients were matched with two controls and 14 were matched with one control. There were no significant differences in patient-, primary care-, or diagnostic intervals between the groups. The information interval was shorter at the DC compared to the control group (difference between matched pairs 7 days, p = 0.001) and the treatment interval was also shorter at the DC with significant differences in the matched analysis (difference between matched pairs 13 days, p = 0.049). The findings remained the same in four sensitivity analyses, made to compensate for differences between the groups. CONCLUSIONS: Up to diagnosis, we could not detect significant differences in time intervals between the DC and the control group. However, the shorter information and treatment intervals at the DC should be advantageous for these patients who will get timely access to treatment or palliative care. Due to limitations regarding comparability between the groups, the results must be interpreted with caution and further research is warranted. TRIAL REGISTRATION: ClinicalTrials.gov-ID: NCT01709539. Registration-date: October 18, 2012.

Self-rated health and venous thromboembolism among middle-aged women: a population-based cohort study.

Venous thromboembolism (VTE) is one of the most common types of cardiovascular diseases (CVDs) and is associated with increased mortality-risk. Poor-self rated health (SHR) has been associated with elevated inflammatory markers and CVDs. However, little is known about as a predictor of incident VTE. To examine the association between self-rated health, lifestyle and incident VTE among middle-aged women. 6917 women aged 50-64 years, followed for 20 years in the Women's Health In the Lund Area (WHILA) study. After exclusion of those who medicated with anticoagulants, were living in nursing homes or suffered from cancer, stroke, VTE or CHD before baseline, a cohort of 5626 women remained. Cox regression was used to analyse the relationship between self-rated health and time to VTE, censored for any of the previous mentioned diseases during follow-up. Data were collected by questionnaires, physical examinations and Swedish registers. In total, 220 women were affected by VTE corresponding to an incidence rate of 3.9 per 1000 person-years. Adjustment for self-rated health did not significantly predict incident VTE, and neither did any of the lifestyle-related habits (e.g. physical activity and dietary habits including alcohol consumption), besides smoking. This study supports previous results with varicose veins and waist circumference as strong predictors of VTE. Poor self-rated health does not seem to be a valid predictor of VTE. Among lifestyle-related parameters, smoking was significantly associated with risk of VTE. We could also confirm the effect of the other already known risk factors.

Diagnostic spectrum and time intervals in Sweden's first diagnostic center for patients with nonspecific symptoms of cancer.

BACKGROUND: Fast-track referral is an increasingly used method for diagnostic evaluation of patients suspected of having cancer. This approach is challenging and not used as often for patients with only nonspecific symptoms. In order to expedite the diagnostics for these patients, we established Sweden's first Diagnostic Center (DC) focusing on outcomes related to diagnoses and diagnostic time intervals. MATERIAL AND METHODS: The study was designed as a prospective cohort study. Patients aged ≥18 years who presented in primary care with nonspecific symptoms of a serious disease were eligible for referral to the DC after having completed an initial investigation. Acceptable diagnostic time intervals were defined to be a maximum of 15 days in primary care and 22 days at the DC. Diagnostic outcome, length of diagnostic time intervals and patient satisfaction were evaluated. RESULTS: A total of 290 patients were included in the study. Cancer was diagnosed in 22.1%, other diseases in 64.1%, and no diagnosis was identified in 13.8% of these patients. Patients diagnosed with cancer were older, had shorter patient interval (time from first symptom to help-seeking), shorter DC-interval (time from referral decision in primary care to diagnosis) and showed a greater number of symptoms compared to patients with no diagnosis. The median primary care interval was 21 days and the median DC interval was 11 days. Few symptoms, no diagnosis, female sex, longer patient interval, and incomplete investigations were associated with prolonged diagnostic time intervals. Patient satisfaction was high; 86% of patients reported a positive degree of satisfaction with the diagnostic procedures. CONCLUSIONS: We demonstrated that the DC concept is feasible with a diagnosis reached in 86.2% of the patients in addition to favorable diagnostic time intervals at the DC and a high degree of patient satisfaction.

Pilot study on increased adherence to physical activity on prescription (PAP) through mindfulness: study protocol.

BACKGROUND: In the Swedish population aged between 50 and 64 years only 7.1% reach the recommended level of physical activity. Physical activity on prescription (PAP) has been used in Sweden since the beginning of the twenty-first century with moderate adherence of approximately 50%. Mindfulness seems to affect motivation to and satisfaction with physical activity. The aim is to test the feasibility of a study in routine care; i.e. to test if mindfulness can improve adherence to PAP, measured by changes in physical activity. METHODS/DESIGN: We will include 90 sedentary individuals, aged 40-65 years, from primary health care centres in Sweden. Individuals will be randomised to only PAP, mindfulness and PAP or mindfulness only. The PAP group will be based on patients' preferences. The mindfulness groups will meet once a week for 8 weeks and practise 20 min of individual training per day. There will not be any motivational interview or physical activity on prescription in the group assigned to only mindfulness. The participants will complete the Five Facet Mindfulness Questionnaire, the Insomnia Severity Index and also answer questions concerning their lifestyle. Physical activity will be measured by ACTi Graph GT1X activity monitor at baseline and after 3 and 6 months. Patients with a severe psychological disease, unstable angina or a recent myocardial infarction will be excluded. The main outcome will be adherence to PAP in an ordinary primary health care setting. In this pilot study, we will also evaluate measures such as the recruitment rate, number of dropouts and adherence to mindfulness practice. DISCUSSION: This study is the first to explore the effect of mindfulness on adherence to PAP and test the feasibility of the study design. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02869854 . Registered on 26 August 2016.

Quantification of mitochondrial DNA copy number in suspected cancer patients by a well optimized ddPCR method.

Changes in mitochondrial DNA (mtDNA) content is a useful clinical biomarker for various diseases, however results are controversial as several analytical factors can affect measurement of mtDNA. MtDNA is often quantified by taking ratio between a target mitochondrial gene and a reference nuclear gene (mtDNA/nDNA) using quantitative real time PCR often on two separate experiments. It measures relative levels by using external calibrator which may not be comparable across laboratories. We have developed and optimized a droplet digital PCR (ddPCR) based method for quantification of absolute copy number of both mtDNA and nDNA gene in whole blood. Finally, the role of mtDNA in suspected cancer patients referred to a cancer diagnostic center was investigated. Analytical factors which can result in false quantification of mtDNA have been optimized and both target and reference have been quantified simultaneously with intra- and inter-assay coefficient variances as 3.1% and 4.2% respectively. Quantification of mtDNA show that compared to controls, solid tumors (but not hematologic malignancies) and other diseases had significantly lower copy number of mtDNA. Higher mtDNA (highest quartile) was associated with a significantly lower risk of both solid tumors and other diseases, independent of age and sex. Receiver operating curve demonstrated that mtDNA levels could differentiate controls from patients with solid tumors and other diseases. Quantification of mtDNA by a well optimized ddPCR method showed that its depletion may be a hallmark of general illness and can be used to stratify healthy individuals from patients diagnosed with cancer and other chronic diseases.

Increased monoaminergic neurotransmission improves compliance with physical activity recommendations in depressed patients with fatigue.

Clinical studies have shown that moderately intense physical activity effectively treats various types of depression. Beneficial effects have been reported in the acute phase of the disease as well as in a long-term perspective. In addition, epidemiological studies have shown that inactivity increases the risk of depression and that exercise prevents relapse. Depressed patients are often prescribed antidepressants, with or without psychotherapy. Some studies have, however, suggested that the most frequently used antidepressants, selective serotonin reuptake inhibitors (SSRIs), contribute to fatigue, which is a common residual symptom associated with depression and the target of the proposed study. Profound fatigue may in turn decrease the ability and motivation to perform the beneficial physical activity, e.g. via executive dysfunction. Fatigue and impaired executive function are commonly linked to disturbed cerebral dopaminergic and noradrenergic neurotransmission. This kind of dysfunction is hard to overcome, even when the major symptoms of depression are alleviated. Interestingly, physical activity has been suggested to improve the dopamine and norepinephrine neurotransmission. Furthermore, the favorable effects may be reciprocal; improved dopamine and norepinephrine transmission in the brain may hypothetically increase the ability and motivation to exercise, since some parts of the brain (e.g. the prefrontal cortex, striatum and cerebellum) that control movement and initiative receive dopaminergic and noradrenergic projections. Based on these findings and assumptions, our hypothesis is that increased dopaminergic and noradrenergic neurotransmission, via intake of a dopamine- and norepinephrine-enhancing agent, improves the compliance with prescribed physical activity in patients with depression and residual fatigue. We also believe that the increased physical activity can prevent relapse into depression, even after interruption of medication. Since increased physical activity also has been shown to improve executive cognitive function, we suggest that executive function should be examined as a secondary outcome together with other possibly related variables such as quality of life, sick leave and BMI.

Study protocol: a multi-professional team intervention of physical activity referrals in primary care patients with cardiovascular risk factors--the Dalby lifestyle intervention cohort (DALICO) study.

BACKGROUND: The present study protocol describes the trial design of a primary care intervention cohort study, which examines whether an extended, multi-professional physical activity referral (PAR) intervention is more effective in enhancing and maintaining self-reported physical activity than physical activity prescription in usual care. The study targets patients with newly diagnosed hypertension and/or type 2 diabetes. Secondary outcomes include: need of pharmacological therapy; blood pressure/plasma glucose; physical fitness and anthropometric variables; mental health; health related quality of life; and cost-effectiveness. METHODS/DESIGN: The study is designed as a long-term intervention. Three primary care centres are involved in the study, each constituting one of three treatment groups: 1) Intervention group (IG): multi-professional team intervention with PAR, 2) Control group A (CA): physical activity prescription in usual care and 3) Control group B: treatment as usual (retrospective data collection). The intervention is based on self-determination theory and follows the principles of motivational interviewing. The primary outcome, physical activity, is measured with the International Physical Activity Questionnaire (IPAQ) and expressed as metabolic equivalent of task (MET)-minutes per week. Physical fitness is estimated with the 6-minute walk test in IG only. Variables such as health behaviours; health-related quality of life; motivation to change; mental health; demographics and socioeconomic characteristics are assessed with an electronic study questionnaire that submits all data to a patient database, which automatically provides feed-back to the health-care providers on the patients' health status. Cost-effectiveness of the intervention is evaluated continuously and the intermediate outcomes of the intervention are extrapolated by economic modelling. DISCUSSIONS: By helping patients to overcome practical, social and cultural obstacles and increase their internal motivation for physical activity we aim to improve their physical health in a long-term perspective. The targeted patients belong to a patient category that is supposed to benefit from increased physical activity in terms of improved physiological values, mental status and quality of life, decreased risk of complications and maybe a decreased need of medication.

Cerebral ischemia induces transcription of inflammatory and extracellular-matrix-related genes in rat cerebral arteries.

Cerebral ischemia results in a local inflammatory response that contributes to the size of the lesion, however, the involvement of the cerebral vasculature is unknown. We hypothesise that the expression of inflammatory genes (Il6, iNOS, cxcl2, TNF-alpha and Il-1beta) and extracellular-matrix-related genes (MMP9, MMP13) is induced in cerebral arteries following cerebral ischemia via activation of mitogen activated kinases (MAPKs). This hypothesis was tested in vivo by experimental subarachnoid haemorrhage (SAH) and temporal middle cerebral artery occlusion (MCAO), and by organ culture of isolated cerebral arteries with quantitative real time PCR (mRNA expression) and immunohistochemistry (localization of protein expression). The gene promoters were investigated in silica with computer analysis. The mRNA analysis revealed that the ischemic models, SAH and MCAO, as well as organ culture of isolated cerebral arteries resulted in transcriptional upregulation of the abovementioned genes. The protein expression involved phosphorylation of three different MAPKs signalling pathways (p38, ERK 1/2 and SAPK/JNK) and the downstream transcription factors (ATF-2, Elk-1, c-Jun) shown by immunohistochemistry and quantified by image analysis. All three models revealed the same pattern of activation in the cerebrovascular smooth muscle cells. The in silica analysis demonstrated binding sites for said transcription factors. The results suggest that cerebral ischemia and organ culture induce activation of p38, ERK 1/2 and SAPK/JNK in cerebral arteries which in turn activate the transcription factors ATF-2, Elk-1 and c-Jun and the expression of inflammatory and extracellular-matrix-related genes in the wall of cerebral arteries.

Cooperative effect of angiotensin AT(1) and endothelin ET(A) receptor antagonism limits the brain damage after ischemic stroke in rat.

Cerebral ischemia results in enhanced expression of smooth muscle cell endothelin and angiotensin receptors in cerebral arteries. We hypothesise that this phenomenon may be detrimental and that acute treatment with a combined non-hypotensive dose of the angiotensin AT(1) receptor inhibitor candesartan and the endothelin ET(A) receptor antagonist ZD1611 reduces the infarct in experimental ischemic stroke. Transient middle cerebral artery occlusion was induced in male Wistar rats by the intraluminal filament technique for 2 h followed by recirculation. The animals received systemic candesartan (0.05 mg/kg/day), ZD1611 (0.15 mg/kg/day), both combined or vehicle with start immediately after the occlusion. After 48 h the rats were sacrificed, the brains sliced and stained with 1% 2, 3, 5-triphenyltetrazolium chloride (TTC) and the volume of ischemic damage determined. The middle cerebral arteries were harvested for immunocytochemical studies of angiotensin AT(1) and endothelin ET(A) receptor expression. Candesartan or ZD1611 did alone not significantly decrease the brain damage or improve neurological scores as compared to vehicle controls. The combined inhibition of angiotensin AT(1) and endothelin ET(A) receptors however decreased the brain damage and improved the neurological scores (both P<0.05). The treatment did not change resting mean arterial blood pressure. In addition, there was an upregulation of angiotensin AT(1) receptors in the ischemic middle cerebral artery smooth muscle cells, which was normalised by the combined treatment. In conclusion, the present study shows that combined inhibition of angiotensin AT(1) and endothelin ET(A) receptors reduces the brain damage and improves the neurological outcome after ischemic stroke in rat.

Protein kinase C inhibition attenuates vascular ETB receptor upregulation and decreases brain damage after cerebral ischemia in rat.

BACKGROUND: Protein kinase C (PKC) is known to be involved in the pathophysiology of experimental cerebral ischemia. We have previously shown that after transient middle cerebral artery occlusion, there is an upregulation of endothelin receptors in the ipsilateral middle cerebral artery. The present study aimed to examine the effect of the PKC inhibitor Ro-32-0432 on endothelin receptor upregulation, infarct volume and neurology outcome after middle cerebral artery occlusion in rat. RESULTS: At 24 hours after transient middle cerebral artery occlusion (MCAO), the contractile endothelin B receptor mediated response and the endothelin B receptor protein expression were upregulated in the ipsilateral but not the contralateral middle cerebral artery. In Ro-32-0432 treated rats, the upregulated endothelin receptor response was attenuated. Furthermore, Ro-32-0432 treatment decreased the ischemic brain damage significantly and improved neurological scores. Immunohistochemistry showed fainter staining of endothelin B receptor protein in the smooth muscle cells of the ipsilateral middle cerebral artery of Ro-32-0432 treated rats compared to control. CONCLUSION: The results suggest that treatment with Ro-32-0432 in ischemic stroke decreases the ischemic infarction area, neurological symptoms and associated endothelin B receptor upregulation. This provides a new perspective on possible mechanisms of actions of PKC inhibition in cerebral ischemia.

MEK1/2 inhibition attenuates vascular ETA and ETB receptor alterations after cerebral ischaemia.

Cerebral ischaemia is associated with elevated levels of endothelin B (ETB) receptors in the ipsilateral middle cerebral artery (MCA). This up-regulation of ET receptors occurs via de novo transcription involving mitogen-activated protein kinases (MAPK). The aim of this study was to examine the effect of inhibition of the MAP kinase/ERK kinase (MEK)1/2 on ET receptor alteration, brain damage, and neurology in experimental cerebral ischaemia. Transient middle cerebral artery occlusion (MCAO) was induced in male Wistar rats by the intraluminal filament technique. The animals received 100 mg/kg intraperitoneally of the MEK1/2 inhibitor U0126 or vehicle in conjunction with the occlusion. After 24 h, the rats were decapitated and the brains removed. The middle cerebral arteries were dissected out and examined with myographs or immunohistochemistry. The ischaemic areas of the brains were compared. After the MCAO, the contractile responses of the ETA and ETB receptors were augmented in the ipsilateral MCA. U0126 decreased this alteration in ET receptor response. Furthermore, treatment with U0126 significantly decreased the brain damage and improved neurological scores. Immunohistochemistry showed that there were lower protein levels of phosphorylated extracellular signal-regulated kinases (ERK)1/2 and phosphorylated transcription factor Elk-1 in the U0126-treated rats compared to control. The results show that treatment with the MEK1/2 inhibitor U0126 in ischaemic stroke decreases brain damage, neurological symptoms, and ET receptor alteration. The vascular effects of U0126 provide new perspective on possible mechanisms of actions of MAPK inhibition in cerebral ischaemia.

Inhibition of PKC activity blocks the increase of ETB receptor expression in cerebral arteries.

BACKGROUND: Previous studies have shown that there is a time-dependent upregulation of contractile endothelin B (ETB) receptors in middle cerebral arteries (MCA) after organ culture. This upregulation is dependent on mitogen-activated protein kinases and possibly protein kinase C (PKC). The aim of this study was to examine the effect of PKC inhibitors with different profiles on the upregulation of contractile ETB receptors in rat MCA. Artery segments were incubated for 24 hours at 37 degrees C. To investigate involvement of PKC, inhibitors were added to the medium before incubation. The contractile endothelin-mediated responses were measured and real-time PCR was used to detect endothelin receptor mRNA levels. Furthermore, immunohistochemistry was used to demonstrate the ETB receptor protein distribution in the MCA and Western blot to measure which of the PKC subtypes that were affected by the inhibitors. RESULTS: The PKC inhibitors bisindolylmaleimide I, Ro-32-0432 and PKC inhibitor 20-28 attenuated the ETB receptor mediated contractions. Furthermore, Ro-32-0432 and bisindolylmaleimide I decreased ETB receptor mRNA levels while PKC inhibitor 20-28 reduced the amount of receptor protein on smooth muscle cells. PKC inhibitor 20-28 also decreased the protein levels of the five PKC subtypes studied (alpha, betaI, gamma, delta and epsilon). CONCLUSION: The results show that PKC inhibitors are able to decrease the ETB receptor contraction and expression in MCA smooth muscle cells following organ culture. The PKC inhibitor 20-28 affects the protein levels, while Ro-32-0432 and bisindolylmaleimide I affect the mRNA levels, suggesting differences in activity profile. Since ETB receptor upregulation is seen in cerebral ischemia, the results of the present study provide a way to interfere with the vascular involvement in cerebral ischemia.

Cerebral ischemia enhances vascular angiotensin AT1 receptor-mediated contraction in rats.

BACKGROUND AND PURPOSE: The aim of the study was to examine how focal cerebral ischemia affects the expression and function of vascular angiotensin II receptors. MATERIALS AND METHODS: We used an intraluminal filament occlusion technique to occlude the right middle cerebral artery (MCA) of the rat. Myographs were used for functional studies of the MCA and real-time polymerase chain reaction, for determination of relative mRNA levels. RESULTS: The contractile responses to angiotensin II were stronger in the right occluded MCA compared with the left MCA and the MCA from sham-operated rats 48 hours after MCA occlusion (P<0.05). The angiotensin II type 1 (AT1) receptor antagonists candesartan and losartan abolished the enhanced responses to angiotensin II (P<0.05), whereas the AT2 receptor antagonist PD123319 had no effect. The amount of AT1 receptor mRNA was lower in the occluded MCAs compared with nonoccluded MCAs 48 hours after occlusion (P<0.05), whereas the mRNA levels of angiotensin converting enzyme (ACE) were higher in the occluded arteries. The mRNA levels of the AT2 receptor and nuclear factor-kappaB were unchanged. CONCLUSIONS: Focal cerebral ischemia in the rat upregulated the contractile responses to angiotensin II in the ipsilateral MCA, and this contraction was mediated by AT1 receptors. Real-time polymerase chain reaction revealed decreased AT1 receptor mRNA levels in the occluded MCA, whereas the amount of ACE mRNA was increased, suggesting locally enhanced angiotensin II production. These results support a role for AT1 receptors in cerebral ischemia, and we think that AT1 receptors might be a future therapeutic target in ischemic stroke.

Effects of tramadol on rat detrusor overactivity induced by experimental cerebral infarction.

OBJECTIVE: Cerebrovascular disease, such as stroke, frequently results in incontinence by reducing suprapontine micturition control. Intraluminal occlusion of the middle cerebral artery (MCA), which produces detrusor overactivity, has been introduced as a useful model of stroke-induced lower urinary tract dysfunction. Recently, the effective analgesic tramadol, was found to possess inhibitory actions on normal rat micturition. The current study aimed to examine the potential effect of tramadol on rat detrusor overactivity due to cerebral infarction. METHODS: In female Sprague-Dawley rats, cerebral ischemia was induced by occlusion of the MCA and the urinary bladder was catheterised. Three days later, continuous cystometry was performed in awake animals and the effects of tramadol given intravenously were studied. RESULTS: In cerebral infarcted rats, bladder capacity was lower (48+/-9%) and micturition pressure higher (76+/-21%) than in control rats. Tramadol 5 mg x kg(-1) given i.v., increased bladder capacity (59+/-29%) and threshold pressure (47+/-32%) to values similar to those in control rats. However, micturition pressure was not significantly altered. Tramadol induced diuresis in some, but not all, cerebral infarcted rats. CONCLUSION: Tramadol normalised detrusor overactivity in MCA-occluded rats. The drug might have a treatment potential in patients with detrusor overactivity after stroke.

Intracellular pathways involved in upregulation of vascular endothelin type B receptors in cerebral arteries of the rat.

BACKGROUND AND PURPOSE: Previous studies have shown that contractile endothelin type B (ETB) receptors are upregulated in cerebral arteries after experimental focal cerebral ischemia. The aim of this study was to examine the upregulation of contractile ETB receptors in cerebral arteries after organ culture and to elucidate the intracellular pathways involved. METHODS: Rat middle cerebral arteries (MCAs) were incubated with or without inhibitors. The vessels were mounted in myographs, and the contractile responses to endothelin-1 (ET-1) (ETA and ETB receptor agonist) and sarafotoxin 6c (ETB receptor agonist) were measured. Levels of ETB receptor mRNA were measured with real-time polymerase chain reaction. RESULTS: In fresh MCA, sarafotoxin 6c had no contractile effect. However, after organ culture, a strong concentration-dependent contraction was induced. ET-1 produced a strong contraction, in which the Emax was unaffected by organ culture but the EC50 was decreased with time. The sarafotoxin 6c-induced contraction after 24 hours of organ culture was attenuated by the transcriptional inhibitor actinomycin D and the translational inhibitor cycloheximide as well as the protein kinase C inhibitor Ro-31-8220. Real-time polymerase chain reaction revealed that the mRNA levels of the ETB receptor were increased after organ culture compared with fresh vessels. Actinomycin D and Ro-31-8220 diminished the enhanced mRNA levels considerably. CONCLUSIONS: The results suggest that, in fresh MCA, the ETA receptor is the most prominent subtype, while after organ culture ETB receptors also contribute to the contraction. This upregulation is due to de novo transcription of receptors. Protein kinase C is involved in the upregulation as Ro-31-8220 attenuates the contraction and the mRNA increase.

Comparison of the antagonistic effects of different angiotensin II receptor blockers in human coronary arteries.

BACKGROUND: Angiotensin II (Ang II) is a potent vasoconstrictor and a deleterious factor in cardiovascular pathophysiology. Ang II receptor blockers (ARBs) have recently been introduced into clinical practice for treatment of hypertension and congestive heart failure. AIMS: This study was undertaken to evaluate the inhibitory effects of ARBs on vasoconstriction in humans. METHODS: Vasomotor tone was analyzed in endothelium denuded, human coronary artery (HCA) segments. Ang II type 1 (AT(1)) and type 2 (AT(2)) receptor mRNA expression was examined by reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: Ang II was a potent vasoconstrictor (pEC(50) = 7.7). At 1 nM of the AT(1) receptor antagonists, candesartan and valsartan, the maximum contraction was depressed to 57 and 50% of Ang II, respectively, indicating insurmountability. Although generally considered surmountable, the presence of 100 nM losartan elicited a depression of the Ang II response to 32%. Its active metabolite, EXP 3174 (1 nM), abolished the Ang II contraction. The AT(1) receptor antagonists had the following order of blocking effect; EXP 3174 > candesartan = valsartan > losartan. The AT(2) receptor antagonist, PD 123319 (100 nM) significantly attenuated the Ang II contraction (E(max) = 62% of Ang II). RT-PCR of HCA smooth muscle cells demonstrated expression of both AT(1) and AT(2) receptor mRNA. CONCLUSIONS: Ang II contraction in HCA is mediated mainly by AT(1) but also involves AT(2) receptors. The active metabolite of losartan, EXP 3174, is the most efficacious AT(1) receptor antagonist in HCA.