Changes in plasma atrial natriuretic peptide after angiocardiography

BACKGROUND:

Angiocardiography is an important diagnostic modality for evaluation of heart disease. It is well known that the concentration of plasma atrial natriuretic peptide (ANP) increases after injection of contrast medium. On the other hand, some patients with hypertension, heart failure or cardiac hypertrophy have an increased plasma ANP concentration at baseline; however, whether ANP increases after angiography in these patients is unknown.

OBJECTIVES:

To investigate changes in plasma ANP concentrations after angiocardiography in patients with high ANP concentrations at baseline.

PATIENTS AND METHODS:

Plasma ANP concentrations of 32 patients with angina pectoris were measured before and after angiocardiography. They were then classified into two groups according to their ANP concentration before examination.

RESULTS:

ANP concentration after the injection of contrast medium increased significantly in patients with normal ANP concentrations before angiography but did not change in patients with high ANP concentrations at rest.

CONCLUSIONS:

These results suggest that the absence of an increase in ANP after angiography may in part be due to reduced sensitivity to the angiography stimulus or to an already maximal activation of ANP secretion at baseline.     

Serum concentration of hyaluronic acid in healthy populations and patients with rheumatoid arthritis--relationship to clinical disease activity of RA

With the sandwich binding protein assay utilizing hyaluronic acid binding protein, we measured serum concentration of hyaluronic acid in 458 healthy persons, 71 patients with rheumatoid arthritis (RA) and 51 patients with various rheumatic diseases such as osteoarthritis (OA), progressive systemic sclerosis (PSS), systemic lupus erythematosus (SLE) and gout. The mean concentration +/- standard deviation (SD) of healthy persons whose age ranged 2 to 92 years old was 38.5 +/- 35.7ng/ml, and those with over 50 years old had apparently higher concentrations (51.9 +/- 40.5ng/ml) than those with below 50 of age (20.6 +/- 14.8ng/ml). When the upper limit of normal range was set up at 130 ng/ml, abnormal percentages were 62.0% (44/71) in RA, 0% (0/18) in OA, 6.3% (1/16) in PSS, 18.2% (2/11) in SLE and 0% (0/6) in gout. Patients who apparently had arthritis but not RA revealed normal or near to the upper limit in serum hyaluronic acid compared to RA patients having the mean +/- SD of 351.4 +/- 463.7ng/ml. When patients with RA were classified into stage I to IV with X ray of bone destruction, patients with more advanced X ray stage showed significantly higher serum concentrations of hyaluronic acid. Similarly, patients with lower activity of daily living revealed significantly higher serum concentrations of hyaluronic acid. In addition, serum hyaluronic acid level did correlate to concentration of serum CRP and sialic acid. Lansbury's index, strength of grip, joint score and erythrocyte sedimentation rate, but did not to duration of morning stiffness and titer of rheumatoid factor.(ABSTRACT TRUNCATED AT 250 WORDS)     

Alteration of the Intestinal Environment by Lubiprostone Is Associated with Amelioration of Adenine-Induced CKD

The accumulation of uremic toxins is involved in the progression of CKD. Various uremic toxins are derived from gut microbiota, and an imbalance of gut microbiota or dysbiosis is related to renal failure. However, the pathophysiologic mechanisms underlying the relationship between the gut microbiota and renal failure are still obscure. Using an adenine-induced renal failure mouse model, we evaluated the effects of the ClC-2 chloride channel activator lubiprostone (commonly used for the treatment of constipation) on CKD. Oral administration of lubiprostone (500 µg/kg per day) changed the fecal and intestinal properties in mice with renal failure. Additionally, lubiprostone treatment reduced the elevated BUN and protected against tubulointerstitial damage, renal fibrosis, and inflammation. Gut microbiome analysis of 16S rRNA genes in the renal failure mice showed that lubiprostone treatment altered their microbial composition, especially the recovery of the levels of the Lactobacillaceae family and Prevotella genus, which were significantly reduced in the renal failure mice. Furthermore, capillary electrophoresis–mass spectrometry-based metabolome analysis showed that lubiprostone treatment decreased the plasma level of uremic toxins, such as indoxyl sulfate and hippurate, which are derived from gut microbiota, and a more recently discovered uremic toxin, trans-aconitate. These results suggest that lubiprostone ameliorates the progression of CKD and the accumulation of uremic toxins by improving the gut microbiota and intestinal environment.     

Losartan modulates muscular capillary density and reverses thiazide diuretic-exacerbated insulin resistance in fructose-fed rats

The renin-angiotensin system (RAS) is involved in the pathogenesis of insulin sensitivity (IS). The role of RAS in insulin resistance and muscular circulation has yet to be elucidated. Therefore, this study sought to determine the mechanisms of angiotensin II receptor blockers (ARBs) and/or diuretics on IS and capillary density (CD) in fructose-fed rats (FFRs). Sprague-Dawley rats were fed either normal chow (control group) or fructose-rich chow for 8 weeks. For the last 4 weeks, FFRs were allocated to four groups: an FFR group and groups treated with the thiazide diuretic hydrochlorothiazide (HCTZ), with the ARB losartan, or both. IS was evaluated by the euglycemic hyperinsulinemic glucose clamp technique at week 8. In addition, CD in the extensor digitorum longus muscle was evaluated. Blood pressure was significantly higher in the FFRs than in the controls. HCTZ, losartan and their combination significantly lowered blood pressure. IS was significantly lower in the FFR group than in the controls and was even lower in the HCTZ group. Losartan alone or combined with HCTZ significantly increased IS. In all cases, IS was associated with muscular CD, but not with plasma adiponectin or lipids. These results indicate that losartan reverses HCTZ-exacerbated insulin resistance, which can be mediated through the modulation of muscular circulation in rats with impaired glucose metabolism.     

Effects of bidisomide (SC-40230), a new class I antiarrhythmic agent,on ventricular arrhythmias induced by coronary artery occlusion and reperfusion in anesthetized rats; comparison with mexiletine and disopyramide

Summary We investigated the antiarrhythmic effects of bidisomide (SC-40230), a new class I antiarrhythmic drug, in early-phase ventricular arrhythmias induced by coronary artery occlusion and reperfusion in anesthetized rats. The effects of bidisomide were compared with those of mexiletine (MXT) and disopyramide (DSP), established class I antiarrhythmic drugs. Drugs were administered intravenously, 5 min before induction of coronary occlusion. Bidisomide (5 mg/kg) reduced the number of premature ventricular complexes and the incidence of ventricular tachycardia and ventricular fibrillation similarly to MXT and DSP in rats with ventricular arrhythmias induced by coronary artery occlusion. In rats with ventricular arrhythmias induced by coronary artery reperfusion following a 5min coronary occlusion, the antiarrhythmic effects of 5 mg/kg of bidisomide were similar to those of the same doses of MXT and DSP. All three drugs significantly slowed the heart rate. Our results suggest that bidisomide may effectively reduce the severity of lifethreatening ventricular arrhythmias that occur during acute coronary syndrome.     

Association of hla-b39 with hla-b27-negative ankylosing spondylitis and pauciarticular juvenile rheumatoid arthritis in japanese patients

Objective. To investigate the characteristics of HLA-B27 that render susceptibility to seronegative spondylarthropathies. Methods. Serologic HLA class I typing of Japanese patients with ankylosing spondylitis (AS), juvenile rheumatoid arthritis (JRA), and healthy controls, was performed. HLA-B39 subtypes were determined by polymerase chain reaction-sequence-specific oligohy-bridization. Results. HLA-B27 was present in 40 of 48 patients with AS (83%), and in only 1 of 210 healthy controls (0.5%). Three of 8 patients (37.5%) who were negative for HLA-B27 were positive for HLA-B39, which was significantly higher compared with the HLA-B27-negative controls (6.2% P = 0.01). Significant association with HLA-B39 was also noted in the JRA patients (16.7%; P < 0.01), especially in those patients with pauciarticular-onset disease (33.3%; P < 0.01). Ten of 13 HLA-B39-positive patients had subtype B^*3901 and 3 had B^*3902. Conclusion. Because HLA-B27 and HLA-B39 share Glu at position 45 and Cys at position 67, both of which constitute components of the peptide-anchoring B pocket, and because they possess similar peptide-ligand motifs, our results may support either the role of the peptides presented by class I antigens or the importance of Cys at position 67, in the development of spondylarthropathies and pauciarticular-onset JRA.