Differences in the cardiovascular hemodynamic response between the Valsalva and Reverse Valsalva Maneuvers in healthy subjects.

BACKGROUND: The Valsalva Maneuver (VM) is the first-line treatment for paroxysmal supraventricular tachycardia, but a recent, novel, and efficient tool to restore sinus rhythm has been described, i.e., the Reverse Valsalva (RV). This study aims to compare changes in cardiovascular hemodynamics and autonomic system activity (ANS) based on heart rate variability (HRV) analysis during both maneuvers. METHODS: Fifteen healthy participants performed the VM and RV maneuvers three times in a sitting position for durations of 15 s and 10 s, respectively. Blood pressure (BP) and heart rate (HR) were continuously monitored before, during and after the tests. Autonomic system activity was evaluated using frequency-domain analysis of HRV. RESULTS: The decrease in HR from baseline to the lowest values, expressed as a ratio, was similar during both maneuvers (0.81 during the RV vs. 0.79 during the VM, p = 0.27). However, the final lowest HR in response to the RV was higher than that in response to the VM, 70/min vs. 59/min (p <0.001). The activation of the autonomic nervous system during the most bradycardic phase of the RV (phase II) and VM (phase IV) showed that the total power of HRV was less prominent during the RV than during the VM (p <0.012), with similar levels of parasympathetic activation. CONCLUSIONS: Our results showed less HR slowdown during the RV than during the VM. The changes in HRV parameters during both procedures in particular phases of the RV and VM suggest that the autonomic nervous system is activated alternately, so these tests can be used complementarily in a clinical setting with different results.

Microvascular angina (Cardiac Syndrome X) from a historical overview, epidemiology, pathophysiology to treatment recommendations - a minireview.

Microvascular angina (MVA) is a condition characterized by the presence of angina-like chest pain, a positive response to exercise stress tests, and no significant stenosis of coronary arteries in coronary angiography, with absence of any other specific cardiac diseases. The etiology of this syndrome is still not known and it is probably multifactorial. Coronary microvascular dysfunction is proposed as the main pathophysiological mechanism in the development of MVA. Altered somatic and visceral pain perception and autonomic imbalance, in addition to myocardial ischemia, has been observed in subjects with MVA, involving dynamic variations in the vasomotor tone of coronary microcirculation with consequent transient ischemic episodes. Other theories suggest that MVA may be a result of a chronic inflammatory state in the body that can negatively influence the endothelium or a local imbalance of factors regulating its function. This article presents the latest information about the epidemiology, diagnostics, etiopathogenesis, prognosis, and treatment of patients with MVA.

Past strong experiences determine acute cardiovascular autonomic responses to acoustic stress.

BACKGROUND: Stress is a major risk factor for cardiovascular (CV) disease. We hypothesized that past strong experiences might modulate acute CV autonomic responses to an unexpected acoustic stimulus. A i m: The study's aim was to compare acute CV autonomic responses to acoustic stress between students with and without a past strong experience associated with the acoustic stimulus. MATERIALS AND METHODS: Twenty five healthy young volunteers - medical and non-medical students - were included in the study. CV hemodynamic parameters, heart rate (HR), and blood pressure (BP) variability were assessed for 10 min at rest and for 10 min after two different acoustic stimuli: a standard sound signal and a specific sound signal used during a practical anatomy exam (so-called "pins"). RESULTS: Both sounds stimulated the autonomic nervous system. The "pins" signal caused a stronger increase in HR in medical students (69 ± 10 vs. 73 ± 13 bpm, p = 0.004) when compared to non-medical students (69 ± 6 vs. 70 ± 10, p = 0.695). Rises in diastolic BP, observed 15 seconds after sound stressors, were more pronounced after the "pins" sound than after the standard sound signal only in medical students (3.1% and 1.4% vs. 3% and 4.4%), which was also reflected by low-frequency diastolic BP variability (medical students: 6.2 ± 1.6 vs. 4.1 ± 0.8 ms2, p = 0.04; non-medical students: 6.0 ± 4.3 vs. 4.1 ± 2.6 ms2, p = 0.06). CONCLUSIONS: The "pins" sound, which medical students remembered from their anatomy practical exam, provoked greater sympathetic activity in the medical student group than in their non-medical peers. Thus, past strong experiences modulate CV autonomic responses to acute acoustic stress.

Cardiovascular response to different types of acute stress stimulations.

INTRODUCTION: Stress is an ubiquitous phenomenon in the modern world and one of the major risk factors for cardiovascular disease. e aim of our study was to evaluate the effect of various acute stress stimuli on autonomic nervous system (ANS) activity, assessed on the basis of heart rate (HRV) and blood pressure (BPV) variability analysis. MATERIALS AND METHODS: the study included 15 healthy volunteers: 9 women, 6 men aged 20-30 years (23.3 ± 1.8). ANS activity was assessed by HRV and BPV measurement using Task Force Monitor 3040 (CNSystems, Austria). ECG registration and Blood Pressure (BP) measurement was done 10 minutes at rest, 10 minutes a er the stress stimulus (sound signal, acoustic startle, frequency 1100 Hz, duration 0.5 sec, at the intensity 95 dB) and 10 minutes after the cold pressor test. The cold pressor test (CPT) was done by placing the person's hand by wrist in ice water (0-4°C) for 120 s. RESULTS: Every kind of stress stimulation (acoustic startle; the CPT) caused changes of HRV indicator values. The time domain HRV analysis parameters (pNN50, RMSSD) decreased after acoustic stress and the CPT, but were significantly lower after the CPT. In frequency domain HRV analysis, significant differences were observed only after the CPT: (LF-RRI 921.23 ms2 vs. 700.09 ms2; p = 0.009 and HF-RRI 820.75 ms2 vs. 659.52 ms2; p = 0.002). The decrease of LF-RRI and HF-RRI value after the CPT was significantly higher than after the acoustic startle (LF-RRI 34% vs. 0.4%, p = 0.022; HF-RRI 19.7% vs. 7% ms2, p = 0.011). The decreased value of the LF and HF components of HRV analysis are indicative of sympathetic activation. Nonlinear analysis of HRV indicated a significant decrease in the Poincare plot SD1 (p = 0.039) and an increase of DFAα2 (p = 0.001) in response to the CPT stress stimulation. The systolic BPV parameter LF/HF-sBP increased significantly after the CPT (2.84 vs. 3.31; p = 0.019) and was higher than after the acoustic startle (3.31 vs. 3.06; p = 0.035). Significantly higher values of diastolic BP (67.17 ± 8.10 vs. 69.65 ± 9.94 mmHg, p = 0.038) and median BP (83.39 ± 8.65 vs. 85.30 ± 10.20 mmHg, p = 0.039) were observed in the CPT group than in the acoustic startle group. CONCLUSIONS: the Cold Pressor Test has a greater stimulatory effect on the sympathetic autonomic system in comparison to the unexpected acoustic startle stress. Regardless of whether the stimulation originates from the central nervous system (acoustic startle) or the peripheral nervous system (CPT), the final response is demonstrated by an increase in the low frequency components of blood pressure variability and a decrease in the low and high frequency components of heart rate variability.

Autonomic dysregulation in colon cancer patients.

To the best of our knowledge, only two studies analyzed the relationship between HRV and carcinoembryonic antigen (CEA) in colon cancer patients. The aim of this study was to analyze changes in the autonomic activity of colon cancer patients using heart rate variability (HRV) and blood pressure variability (BPV) measures, and to verify if HRV and BPV parameters correlate with hemodynamic indices in this group and the plasma levels of CEA. Presence of colon cancer is associated with changes in autonomic activity, namely parasympathetic-sympathetic imbalance in form of sympathetic overdrive. Cancer-related autonomic dysfunction may contribute to impairment of gastrointestinal motility.

Nutritional parameters and carbohydrate and fat metabolism after prolonged salsolinol administration in rats fed normal or high-fat diets.

OBJECTIVES: Previous studies have reported that exogenous salsolinol might contribute to myenteric cell death and altered gastrointestinal motility. Because the entire gut mucosal, entero-endocrine and motor functions are integrated by the enteric nervous system, the aim of the present study was to investigate if prolonged intraperitoneal salsolinol administration alters basic metabolism and nutritional parameters in adult Wistar rats fed normal or high-fat diets. METHODS: Male Wistar rats were subjected to continuous intraperitoneal low dosing of salsolinol with ALZET osmotic mini-pumps for 2 or 4 weeks and fed either a normal or high-fat diet. Appropriate groups served as the controls. Nutritional status (food intake, body weight, and epididymal fat pads weight), residual solid food in the stomach and biochemical parameters (GIP, GLP-1, CRF, glucose, TG, LDL, HDL) were assessed. RESULTS: Prolonged salsolinol treatment significantly reduced total body mass and adipose tissue accumulation. The effects were more pronounced in the salsolinol-treated rats fed a high-fat diet. In salsolinol-treated rats, serum postprandial GIP levels were elevated, and serum postprandial GLP-1 levels were lower compared with the appropriate controls. CONCLUSIONS: Salsolinol might influence the regulatory mechanisms of body weight and epididymal fat pad accumulation through neurohormonal pathways.

The dynamics of autonomic nervous system activity and hemodynamic changes in pregnant women.

OBJECTIVE: The purpose of this research was to assess the dynamics of autonomic nervous system(ANS) and hemodynamic activity changes during uncomplicated pregnancy. METHODS: We enrolled 36 pregnant women (mean age 29 ± 4.8 years) and a control group of 10 non-pregnant women (mean age 25.9 ± 0.88 years). The examination was performed in the 1st, 2nd, and 3rd trimester. Continuous registration of BP, ECG, and cardioimpedance was performed with Task Force Monitor 3040i. ANS activity was measured using the following parameters: HRV, BPV, BRS at rest, and in response to autonomic tests. RESULTS: Compared to the 1st trimester, an increase in HR (73 vs. 92 bpm; p < 0.001) and mean BP (80 vs. 85 mmHg, p < 0.01) was observed in the 3rd trimester. In the 1st trimester, the BRS of pregnant women was insignificantly higher than in the controls (24.8 vs. 22.3 ms/mmHg); subsequently, it decreased significantly, to 13.4 ms/mmHg in the 3rd trimester (p = 0.0004). An increase in nLF (39.57 ± 13.75 vs. 58.73 ± 15.55; p = 0.001) and LF/HF ratio (1.03 ± 0.76 vs. 1.85 ± 0.8; p < 0.00002) was revealed in HRV analysis conducted in the 3rd trimester, as compared to the 1st tri- mester, along with a decrease in nHF (60.43 ± 13.71 vs. 41.26 ± 15.55; p < 0.001). An increase in LF/HF-sBPV (1.05 ± 0.48 vs. 1.58 ± 0.44; p = 0.01) was recorded in BPV analysis at rest in the 3rd trimester as compared to the respective 1st trimester value. CONCLUSION: Our findings suggest that pregnancy is associated with dynamic changes in autonomic balance, namely doubled dominance of the sympathetic component. Hypervolemia seems the major factor responsible for autonomic and hemodynamic changes observed during pregnancy, as it causes an increase in BP and simultaneous decrease in BRS.

Ghrelin, pancreatic polypeptide plasma concentrations and gastric myoelectric activity in celiac disease.

BACKGROUND/AIMS: The aim of the study was to analyze the effect of celiac disease(CED) on the upper-gut motility and release of enteral hormones (ghrelin and pancreatic peptide (PP)). MATERIALS AND METHODS: the study included 25 patients diagnosed with CED and 30 healthy controls. Gastric myoelectric activities (EGG) in a fasted and fed state were recorded. The plasma concentrations of ghrelin and PP were determined. R e s u l t s: CED patients presented in a fasted state a decreased percentage of normogastria 54.8 ± 24.5 vs. 86 ± 12.3%, p = 0.02 and slow wave coupling (SWC) 52.7 ± 13.4 vs. 77.4 ± 11.9%; p = 0.00001 with increased dominant power (DP) 11.6 ± 1.5 vs. 11.1 ± 1.1. Contrary to the controls, they did not show an improvement in the percentage of normogastria, DP and SWC when examined in a fed state (p 〈0.05). Furthermore, CED patients presented with significantly lower fasting plasma concentrations of ghrelin 156.8 ± 86.7 vs. 260.2 ± 87.6 pg/ml, p = 0.0002 and significantly higher fasting PP levels than did the controls 265.2 ± 306.3 vs. 54.1 ± 54.6 pg/ml, p = 0.0005. C o n c l u s i o n: CED affects gastric myoelectric activity (decreasing normogastria and coupling) and causes changes in fasting concentrations of enteral hormones (decrease in ghrelin and an increase in PP). Gastric myoelectric response to food is abolished in CED patients, probably due to the neurohormonal changes induced by primary inflammation associated with this disease.

[Evaluation of heart rate and blood pressure variability in Parkinson's disease patients after bilateral subthalamic deep brain stimulation]. / Ocena zmiennosci rytmu serca i cisnienia tetniczego u osób z choroba Parkinsona po obustronnej glebokiej stymulacji jadra niskowzgórzowego.

INTRODUCTION: Autonomic dysfunctions are the most common non-motor symptoms of Parkinson's disease (PD) and often precede the motor symptoms of the disease. Autonomic dysfunction may be a dominant symptom of the advanced stages of PD as well as a major cause of patient disability. Despite the wide use of neurostimulation in clinical practice, the effect of deep brain stimulation of subthalamic nucleus (STN DBS) on autonomic symptoms of PD still remains only partially understood. The aim of the study is evaluation of heart rate variability (HRV) and blood pressure variability (BPV) in patients with PD before STN DBS and following bilateral STN DBS. MATERIAL AND METHODS: The study included 25 subjects aged between 31 and 71 years, diagnosed with the idiopathic PD and selected for treatment with STN DBS. All the patients were in advanced stages of PD, disease duration ranged from 5 to 22 years. The patients enrolled into this study underwent STN DBS. Neurological examination including assessment of the severity of parkinsonism according to UPDRS scale, a psychological examination and an electrophysiological examination of autonomic disturbances based on heart rate and blood pressure variability were conducted on all patients two weeks before and three months after STN DBS. RESULTS: After STN DBS an improvement in terms of the analyzed parts of the UPDRS has been shown. The improvement of motor disorders assessed by III part UPDRS during the "off" medication/stimulation "on" was 67.8%. Orthostatic hypotension before the STN DBS procedure was observed in 56% of patients and after STN DBS in 53% of them. Before STN DBS the imbalance of the sympathetic--parasympathetic components with the predominance of the sympathetic based on HRV parameters--the ratio LF/HF-RRI (2.5) and a higher rate of LFnu (61.3%) than HFnu (38.6%) has been shown. Three months post STN DBS an increase parameters of spectral analysis of HRV in the low frequency LF-RRI, and high-frequency HF-RRI and the total power spectrum PSD-RRI was observed. After STN DBS an increase of parameters of spectral analysis of systolic BPV, very low frequency VLF-sBP, low frequency LF-sBP and total power spectrum PSD-sBP was noted. CONCLUSIONS: Results of the study suggest that STN DBS is an effective treatment method of both motor symptoms and autonomic dysfunctions. The disturbances of HRV and BPV before and after STN DBS indicate the increase of autonomic system activity with sympathetic dominance.

The influence of prostaglandin PGE1 and PGF2alpha analogues on autonomic nervous system activity, estimated with heart rate variability, in cyclophosphamide-induced hemorrhagic cystitis in rats.

UNLABELLED: The cyclophosphamide-induced hemorrhagic cystitis (CP-HC) is a common consequence of cyclophosphamide treatment with complex pathophysiology involving several inflammatory mechanisms and autonomic nervous system dysregulation. THE AIM OF THIS STUDY: To determine effects of prostaglandin PGE1 and PGF2alpha analogues on the activity of the autonomic nervous system (ANS), estimatedindirectly on the basis of heart rate variability (HRV), in an experimental model of cyclophosphamide-induced hemorrhagic cystitis (CP-HC). Moreover we verified if potential changes in autonomic regulation can contribute to uroprotective role of prostaglandins. MATERIAL AND METHODS: The study included three groups of rats with experimentally induced CP-HC. The animals from group 2 and 3 were administered PGE1 and PGF2a analogues, respectively, and the rats from group 1 (controls) did not receive any treatment. The HRV of animals from all the groups was analyzed after seven days of the experiment. RESULTS: Administration of both PGF2alpha and PGE1 was associated with an increase in the power of VLF component and total power on frequency-domain analysis. Moreover, a significant increase in the power of non-normalized components, LH and HF, and two parameters of time-domain analysis, SDN-N and rMSSD, was documented in PGF2alpha-administered animals. Both prostaglandin-treated groups did not differ significantly from the controls in terms of the values of normalized parameters, nLF and nHF. CONCLUSIONS: The analyzed prostaglandin analogues increased total autonomic activity but did not induced preferential changes in sympathetic or parasympathetic activity. Nevertheless, the VLF changes documented on HRV analysis may reflect a decrease in the level of certain pro-inflammatory mediators, thus pointing to, previously postulated in literature, potential beneficial uroprotective effect of prostaglandins in CP-HC.

Associations between gut microbiota characteristics and non-motor symptoms following pharmacological and surgical treatments in Parkinson's disease patients.

BACKGROUND: The gut microbiota has been implicated in Parkinson's disease (PD), with alterations observed in microbial composition and reduced microbial species richness, which may influence gastrointestinal symptoms in PD patients. It remains to be determined whether the severity of gastrointestinal symptoms correlates with microbiota variations in PD patients treated pharmacologically or with subthalamic nucleus deep brain stimulation (STN-DBS) therapy. This study aims to explore how these treatments affect gut microbiota and gastrointestinal symptoms in PD, identifying specific microbial differences associated with each treatment modality. METHODS: A total of 42 individuals diagnosed with PD, along with 38 age-matched household control participants, contributed stool samples for microbiota characterization. Differences in the gut microbiota across various groups of PD patients and their households were identified through comprehensive sequencing of the 16S rRNA gene amplicon sequencing. KEY RESULTS: Differences in microbial communities were observed between PD patients and controls, as well as between PD patients receiving pharmacological treatment and those with STN-DBS. Pharmacologically treated advanced PD patients have higher gastrointestinal dysfunctions. Gut microbiota profile linked to STN-DBS and reduced levodopa consumption, characterized by its anti-inflammatory properties, might play a role in diminishing gastrointestinal dysfunction relative to only pharmacological treatments. CONCLUSIONS & INFERENCES: Advanced PD patients on medication exhibit more gastrointestinal issues, despite relatively stable microbial diversity, indicating a complex interaction between gut microbiota, PD progression, and treatment effects. An imbalanced gut-brain axis, particularly due to reduced butyrate production, may lead to constipation by affecting the enteric nervous system, which emphasizes the need to incorporate gut microbiome insights into treatment strategies.

The changes of heart rate variability in response to deep breathing in professional swimmers.

INTRODUCTION: The analysis of heart rate variability (HRV) is a useful tool for the evaluation of adaptation processes of autonomic nervous system (ANS) to physical exercise. The deep breathing test (DB) induces the increased activity of the parasympathetic component of ANS. The aim of the study was to evaluate the influence of DB on ANS activity in professional swimmers and non-trained persons. METHODS: The study included 10 healthy swimmers (5 women and 5 men, mean age 21 ± 2 yrs) in the transitory phase of their training cycle, and a control group comprising 31 healthy volunteers. The evaluation of ANS activity was based on the time and frequency domain indices of HRV determined at rest and during DB. RESULTS: Compared to the controls, swimmers were characterized by significantly higher values of the following HRV indices determined at rest: mRR (902.9 ± 102.5 ms vs. 744 ± 67.5 ms, p <0.05), rMSSD (71.4 ± 46.9 ms vs. 41.3 ± 20.7 ms, p <0.05), pNN50 (28.3 ± 17.4% vs.14 ± 10.7%, p <0.05), LF (603.5 ± 208.2 ms2 vs. 445.2 ± 137 ms2, p <0.03). Also during DB test, the values of the following HRV indices of the swimmers were significantly higher than in the controls: mRR (899.2 ± 69.2 ms vs. 766.4 ± 63.6 ms, p <0.05), SDNN (114.1 ± 45.1 ms vs. 79 ± 27.7 ms, p <0.05), rMSDD (81.9 ± 38.2 ms vs. 50.7 ± 27 ms, p <0.05), pNN50 (32.9 ± 14.3 % vs. 20.6 ± 14.6%, p <0.05), TP (1972.7 ± 809.5 ms2 vs. 1329.7 ± 532 ms2, p <0.05), HF (657.1 ± 330.9 ms2 vs. 405.7 ± 217 ms2, p <0.05), LF (753.3 ± 294 ms2 vs. 533 ± 213.4 ms2, p <0.05). The analysis of value relative DB-induced changes in time and frequency domain HRV indices revealed significant intergroup differences in reaction to parasympathetic stimulation. CONCLUSIONS: Based on the results presented in this study, the swimmers' response to deep breathing seems stronger than in persons without professional training. The deep breathing test may be a useful tool to evaluate the dynamic changes in the parasympathetic activity of ANS of sportspersons.

Efficacy of deep brain stimulation of the subthalamic nucleus on autonomic dysfunction in patients with Parkinson's disease.

Subthalamic nucleus (STN) deep brain stimulation (DBS) is well established for the treatment of the motor symptoms of Parkinson's disease (PD). However, the effect of STN DBS on autonomic symptoms has not been well studied. We examined 19 patients undergoing STN DBS for PD. The patients were administered a questionnaire to evaluate the pre-operative and post-operative autonomic function. All patients reported a significant post DBS improvement of one or more symptoms of the autonomic dysfunction (urinary and gastrointestinal function). In particular, we have shown the most significant improvement in the urinary function after STN DBS. Further larger studies are required with respect to the effect of STN DBS on the autonomic function.

Postprandial effect of gastrointestinal hormones and gastric activity in patients with irritable bowel syndrome.

Altered gut regulation, including motor and secretory mechanisms, is characteristic of irritable bowel syndrome (IBS). The severity of postprandial symptoms in IBS patients is associated with discomfort and pain; gas-related symptoms such as bloating and abdominal distension; and abnormal colonic motility. The aim of this study was to assess the postprandial response, i.e., gut peptide secretion and gastric myoelectric activity, in patients with constipation-predominant IBS. The study was conducted on 42 IBS patients (14 males, 28 females, mean age 45.1 ± 15.3 years) and 42 healthy participants (16 males, 26 females, mean age 41.1 ± 8.7 years). The study assessed plasma gut peptide levels (gastrin, CCK-Cholecystokinin, VIP-Vasoactive Intestinal Peptide, ghrelin, insulin) and gastric myoelectric activity obtained from electrogastrography (EGG) in the preprandial and postprandial period (meal-oral nutritional supplement 300 kcal/300 ml). Mean preprandial gastrin and insulin levels were significantly elevated in IBS patients compared to the control group (gastrin: 72.27 ± 26.89 vs. 12.27 ± 4.91 pg/ml; p < 0.00001 and insulin: 15.31 ± 12.92 vs. 8.04 ± 3.21 IU/ml; p = 0.0001), while VIP and ghrelin levels were decreased in IBS patients (VIP: 6.69 ± 4.68 vs. 27.26 ± 21.51 ng/ml; p = 0.0001 and ghrelin: 176.01 ± 88.47 vs. 250.24 ± 84.55 pg/ml; p < 0.0001). A nonsignificant change in the CCK level was observed. IBS patients showed significant changes in postprandial hormone levels compared to the preprandial state-specifically, there were increases in gastrin (p = 0.000), CCK (p < 0.0001), VIP (p < 0.0001), ghrelin (p = 0.000) and insulin (p < 0.0001). Patients with IBS showed reduced preprandial and postprandial normogastria (59.8 ± 22.0 vs. 66.3 ± 20.2%) compared to control values (83.19 ± 16.7%; p < 0.0001 vs. 86.1 ± 9.4%; p < 0.0001). In response to the meal, we did not observe an increase in the percentage of normogastria or the average percentage slow-wave coupling (APSWC) in IBS patients. The postprandial to preprandial power ratio (PR) indicates alterations in gastric contractions; in controls, PR = 2.7, whereas in IBS patients, PR = 1.7, which was significantly lower (p = 0.00009). This ratio reflects a decrease in gastric contractility. Disturbances in the postprandial concentration of gut peptides (gastrin, insulin and ghrelin) in plasma may contribute to abnormal gastric function and consequently intestinal motility, which are manifested in the intensification of clinical symptoms, such as visceral hypersensitivity or irregular bowel movements in IBS patients.

Autonomic nervous system activity in constipation-predominant irritable bowel syndrome patients.

BACKGROUND: The main mechanism underlying irritable bowel syndrome is currently believed to be a dysfunction of the brain-gut axis. Autonomic nervous system dysfunction can contribute to development of irritable bowel syndrome symptoms by disturbing visceral sensations. MATERIAL/METHODS: Thirty patients with a diagnosis of constipation-predominant irritable bowel syndrome and 30 healthy volunteers were included in the study. Resting and functional autonomic nervous system tests and percutaneous electrogastrography were performed. Plasma adrenalin, noradrenalin, insulin, ghrelin and cholecystokinin activity was analyzed. RESULTS: Increased sympathetic activation with disturbed parasympathetic function was demonstrated. Patients had substantially higher plasma catecholamine concentration, which confirms sympathetic overbalance. Hyperinsulinemia may explain sympathetic predominance followed by gastric and intestinal motility deceleration. Abnormal, reduced ghrelin and cholecystokinin titre may disturb brain-gut axis functioning and may be responsible for gastric motility deceleration. In electrogastrography, distinctly lower values of fasting normogastria percentage and dominant power were observed. Patients had substantially lower slow wave coupling percentage both in fasting and postprandial periods, which negatively correlated with plasma catecholamines level. Gastric myoelectrical activity disturbances may result from lack of sympatho-parasympathetic equilibrium. CONCLUSIONS: Central sympathetic influence within the brain-gut axis is most probably responsible for myoelectrical activity disturbances in irritable bowel syndrome patients.

Gastric dysfunction in dialysed patients with chronic renal failure.

BACKGROUND: Gastric motor functions are disturbed in patients with chronic renal failure (CRF). The aim of this study was to find the relationship between GI symptoms, gastric myoelectrical activity and regulatory peptides (gastrin, motilin, VIP, CCK) in patients with CRF treated with hemodialyses (HD) and peritoneal dialyses (CAPD). METHODS: Gastric myoelectric activity was evaluated with cutaneously recorded electrogastrographs (EGGs) measurement in: group A: 23 pts with CRF treated with CAPD, group B: 21 pts treated with HD and group C: 48 matched healthy controls. GI symptoms severity was quantified with specially designed questionnaire. The laboratory evaluation of plasma parameters, such as: gastrin, motilin, VIP and CCK was performed. RESULTS: The patients with CRF treated with CAPD and HD showed a significantly lower percentage of normal 2-4 cpm wave's rhythm in both fasting (65.3 +/- 29.3% vs 43.5 +/- 35.9% vs 86.4 +/- 10.2%) and fed conditions (72.7 +/- 34.2% vs 69.5 +/- 22.1% vs 89.3 +/- 9.5%) in comparison to controls. In the fasting state, none of the healthy controls had an abnormal EGG, whereas the 27 patients with CRF (61.3%) had an abnormal EGG. In the fed state the 18 patients with CRF (40.9%). No significant increase of the dominant power (PDP) after meal in CRF patients was observed. The plasma concentrations of gastrin, CCK were increased in fasted and fed CRF patients, whereas VIP and motilin only in fed state. CONCLUSIONS: The patients with CRF showed impaired gastric myoelectrical activity in response to food and high levels of GI hormones. Gastric dysmotility and high peptides appears to be partially responsible for GI symptoms.

Terlipressin facilitates gastric and autonomic system dysfunctions in liver cirrhosis.

BACKGROUND/AIMS: The aim of this study was to evaluate gastric myoelectric activity and autonomic activity in patients with esophageal varices treated by an analogue of vasopressin. METHODOLOGY: Included in this study are 20 patients divided into two groups: Group A: 10 patients treated with terlipressin (the bleeding from oesophageal varices) and Group B: 10 healthy persons matched with age and gender. The studies were performed before and after intravenous administration of vasopressin (VP) analogue. In both groups the fasting plasma levels of vasopressin, adrenaline and noradrenaline were measured by immunochemistry. RESULTS: In group A disturbances of gastric myoelectric activity with high timing of dysrhythmic pattern were observed before VP. VP administration further increased the timing of gastric dysrhythmia from 35 ± 16 to 41 ± 13%, and decreased PDF from 1.4 ± 0.6cpm to 1.19 ± 0.6cpm, PDP from 1891 ± 851µV2 to 718 ± 678µV2. VP induced an increase in SDANN, lnLF, nLF (p<0.05) as well as a decrease in SDNN, pNN50, lnHF (p<0.05). Although there was no retching or vomiting, 80% of patients presented with nausea and exhibited a significant increase in plasma levels of VP, adrenaline and noradrenaline after administration of VP analogue. CONCLUSIONS: VPinduced gastroparesis is characterized by suppressed slow wave amplitude and with increase of their frequency. The existing parasympathetic impairment and increased sympathetic drive of the autonomic system is responsible for vasopressin-induced gastric dysrrhythmia and its clinical consequences.

The ameliorating effect of exogenous melatonin on urinary bladder function in hyperosmolar bladder overactivity and its influence on the autonomic nervous system activity.

This study was designed to investigate the effects of melatonin on the bladder hyperactivity in hyperosmolar-induced overactive bladder (OAB) rats. Additionally, the influence of melatonin on the autonomic nervous system (ANS) using heart rate variability (HRV) analysis was assessed. 40 rats were divided into four groups: I--control (n = 12), II--rats with hyperosmolar OAB (n = 6), III--rats with melatonin pretreatment and hyperosmolar OAB (n = 6) and IV--control with melatonin pretreatment (n = 6). In group III and IV melatonin in dose of 100 mg/kg was given. HRV measurements in 10 rats, as follow: control (n = 2), control after melatonin treatment (n = 2), rats with hyperosmolar OAB without (n = 3), and after (n = 3) melatonin treatment were conducted. This study demonstrates marked influence of melatonin on urinary bladder activity in hyperosmolar-induced OAB rats. These rats showed significantly reduced the detrusor motor overactivity resulting in the improvement of cystometric parameters after melatonin treatment when compared to the control, as follow: a significant increase of intercontraction interval (70%) and functional bladder capacity (67%), as well as a decrease of the basal pressure, detrusor overactivity index and motility index of 96%, 439% and 40%, respectively. ANS activity analysis revealed sympathetic overactivity in OAB rats, and parasympathetic superiority in melatonin treated OAB rats. Melatonin treatment in rats with hyperosmolar OAB (group III) caused significant increase of nuHF parameter (from 51.00 +/- 25.29 to 76.97 +/- 17.43), as well as a decrease of nuLF parameter (from 49.01 +/- 25.26 to 23.03 +/- 17.43) and LF/HF ratio (from 1.280 +/- 0.980 to 0.350 +/- 0.330). In conclusion, melatonin suppresses hyperosmolar OAB, and modulates ANS activity by inhibition of the sympathetic drive. Therefore, melatonin may become a useful agent for OAB management.

Assessments of plasma acyl-ghrelin levels in Parkinson's disease patients treated with deep brain stimulation.

Gastrointestinal dysfunction is the most common non-motor symptom in Parkinson's disease (PD) with rates rising as the disease progresses. Deep brain stimulation of subthalamic nucleus (STN DBS) improves motor functions in advanced PD. However, the effect of STN DBS on ghrelin concentration and consequently on motility disturbances as well as body weight is unclear. The objective of this study was to assess acyl-ghrelin levels in comparison to weight in advanced PD patients treated with STN DBS. Plasma concentrations of acyl-ghrelin was measured in 29 PD patients in the fasting state and at 30, 60, 120, and 180 min after a standard meal preoperatively and 3 months after surgery. The level of acyl-ghrelin in PD patients were compared with 30 age and sex-matched healthy controls. We reported that mean plasma acyl-ghrelin levels were decreased in PD patients before STN DBS in fasting (p = 0.0003) and in 30 min postprandial phase (p = 0.04) compared with healthy controls. The plasma acyl-ghrelin levels after STN DBS increased in pre-prandial and postprandial phase in PD patients at the investigated time points. Body weight gained on average 2.33 kg during the first 3 months after surgery. There was no correlation between the acyl-ghrelin plasma levels and BMI. After STN DBS in fasting and postprandial phase plasma acyl-ghrelin levels were increased. The results showed that STN DBS therapy elicited a modification of ghrelin levels, increasing its concentration in pre- and postprandial state. In addition, body weight was increased during 3 months after surgery.

Comparison of cardiac and gastric responses to vagal stimulation in hypertensive women.

BACKGROUND: The aim was to evaluate the interactions between the effects of vagal stimulation by sham feeding (nonbaroreflex) and deep breathing (baroreflex) on heart rate variability (HRV) and gastric myoelectrical activity (GMA) in pre- and postmenopausal women with essential hypertension. MATERIAL/METHODS: One hundred five post- and premenopausal women with hypertension and 60 premenopausal normotensive women were observed. The study protocol consisted of 5 min of resting HRV followed by 5 min of deep breathing (DB), then 6 min of sham feeding (SF) with 30-min electrogastrography (EGG) before and after SF. The fasting plasma level of noradrenalin was measured. RESULTS: The HRV parameter values at rest in the hypertensive group were half those in the control group (p<0.05). There were notably higher HRV parameter values in the premenopausal women. Plasma noradrenalin level was higher in the postmenopausal women (p=0.0009). The effect of DB was similar before and after menopause; however, HRV parameters in response to DB were lower in the hypertensive women than in the controls (p<0.05). In the controls there was a marked increase in the main HRV parameters in response to DB. In fasting electrogastrography the lowest normogastria percentage was observed in the postmenopausal women. EGG showed that only SF significantly affected the period dominant power (PDP) in all groups and the bradygastria percentage in the postmenopausal women. CONCLUSIONS: This study suggests that the interactions that occur between the effects of non-baroreflex and baroreflex vagal stimulation in hypertensive women may contribute to gastric motility disorders and dyspeptic symptoms.