Dairoku Shirai

Plasma lnterleukin-6 Levels in Continuous Ambulatory Peritoneal Dialysis and Hemodialysis Patients

Plasma levels of interleukin-6 (IL-6), a cytokine known to be involved in lymphocyte activation and in inflammation, were studied in 10 normal volunteers, 21 continuous ambulatory peritoneal dialysis

Niceritrol reduces plasma lipoprotein(a) levels in patients undergoing maintenance hemodialysis

Lp(a) is an LDL-like lipoprotein carrying the apoprotein(a) glycoprotein and has recently been recognized to be an independent risk factor for coronary heart disease. We studied plasma Lp(a) levels in 40 patients undergoing maintenance hemodialysis (24 male, 16 female; aged 16-83 years). Fasting plasma Lp(a) levels were measured by an enzyme-linked immunosorbent assay. The median value of plasma Lp(a) concentrations in hemodialysis patients was significantly higher than that of the normal volunteers (26.0 +/- 2.7 vs. 10.8 +/- 3.7 mg/dL, p < .05). Lp(a) levels did not correlate with age, duration of hemodialysis, total cholesterol, triglyceride, HDL cholesterol, or LDL cholesterol. The 11 patients whose plasma Lp(a) concentrations exceeded 20 mg/dL received niceritrol, a prodrug of nicotinic acid, at a dosage of 500 mg t.i.d. for 4 weeks. The plasma Lp(a) levels were significantly lower after 4 weeks of treatment (38.3 +/- 4.2 vs. 31.5 +/- 3.2 mg/dL, p < .01).

Changes of Plasma Atrial and Brain Natriuretic Peptide Levels During Hemodialysis

OBJECTIVES The purpose of this study was to evaluate the effect of hemodialysis on the plasma concentration of atrial and brain natriuretic peptides, and to determine the two-dimensional echocardiographic parameters affecting the changes of plasma atrial and brain natriuretic peptide levels in patients with chronic renal failure. BACKGROUND Brain natriuretic peptide has been found in human cardiac tissue and increases in patients with congestive heart failure. However, the factors that stimulate the secretion of plasma brain natriuretic peptide have not yet been fully clarified. METHODS In 15 patients with chronic renal failure, plasma atrial and brain natriuretic peptide levels and two-dimensional echocardiographic parameters were measured before and after each session of hemodialysis. RESULTS Plasma atrial natriuretic peptide levels significantly decreased from 367 +/- 537 pg/mL to 138 +/- 167 pg/mL after hemodialysis (p < 0.01). However, plasma brain natriuretic peptide levels did not significantly change after hemodialysis. Left atrial dimension significantly decreased (41.1 +/- 6.6 vs. 36.3 +/- 6.2 mm, p < 0.01) and left ventricular end-diastolic dimension slightly decreased after hemodialysis (57.0 +/- 10.3 vs. 55.7 +/- 9.9 mm, p < 0.05). The decrease of left atrial dimension was greater than that of left ventricular end-diastolic dimension (4.9 +/- 1.6 vs. 1.3 +/- 0.6 mm, p < 0.05). Plasma brain natriuretic peptide levels significantly correlated with fractional shortening both before and after hemodialysis (r = 0.65, p < 0.05). CONCLUSION Plasma atrial natriuretic peptide levels significantly decreased as the right and left atrial overloads decreased, and plasma brain natriuretic peptide levels did not significantly decrease after hemodialysis. Plasma brain natriuretic peptide levels were not significantly influenced by acute hemodynamic change, such as hemodialysis. However, plasma brain natriuretic peptide levels were significantly correlated with basic cardiac function.

Effect of colchicine on the osmotic water flow across the toad urinary bladder

Osmotic water movement across the toad urinary bladder in response to both vasopressin and cyclic AMP was inhibited by 10(-5) to 10(-4) M colchicine on the serosal but not on the mucosal side. This inhibitory effect was found to be time- and dose-dependent. Colchicine alone did not change basal osmotic flow and a baseline of the short-circuit current (Isc) and also did not affect a vasopressin-induced rise of the Isc. The inhibitory effect was not prevented by the addition of pyruvate. The osmotic water movement produced by 360 mM Urea (mucosal), 360 mM mannitol (serosal) or 2 mug/ml amphotericin B (mucosal), was not affected by 10(-4) M colchicine. These results suggest that colchicine inhibits some biological process subsequent to the formation of cyclic AMP except a directional cytoplasmic streaming process where microtubules may be involved.

Effect of different prostaglandins on the permeability of the toad urinary bladder

Abstract 1. PGE 1 alone induced no significant change in osmotic water flow, but stimulated the short-circuit current and inhibited vasopressin- and theophylline-induced osmotic flow across the urinary bladder of the toad, Bufo bufo japonicus . 2. The vasopressin-induced osmotic flow was also inhibited by PGE 2 , PGF 1 α , PGF 2 α , PGA 1 , PGA 2 , PGB 1 and PGB 2 . The potency of this effect was PGE ⩾ PGF > PGB > PGB, and 1 series > 2 series. 3. Among these prostaglandins PGE 1 exhibited the most striking stimulatory effect on the short-circuit current.

Elevated Serum Pepsinogens in Chronic Renal Failure Patients

Human pepsinogens, the precursors of pepsin, originating from the stomach mucosa, are classified into two biochemically distinct groups, namely pepsinogen I (PG I) and pepsinogen II (PG II). We studied the serum levels of PG I and II in 51 normal volunteers, 23 chronic glomerulonephritis patients, 21 continuous ambulatory peritoneal dialysis (CAPD) patients and 40 hemodialysis patients. Serum pepsinogen levels were measured with a competitive binding double antibody radioimmunoassay. In the group of chronic glomerulonephritis patients, a positive correlation between the serum creatinine and the pepsinogen levels were found. The serum pepsinogen levels were remarkably elevated in CAPD and hemodialysis patients. The median levels of post-hemodialysis PG I (265.4 +/- 165.2 ng/ml) and PG II (41.7 +/- 38.0 ng/ml) were significantly higher than prehemodialysis values (PG I 207.4 +/- 127.5 ng/ml, PG II 29.0 +/- 16.6 ng/ml). Pepsinogen release by isolated gastric glands of guinea pigs was suppressed by guanidinosuccinic acid and was facilitated by calcium. The data suggest that both removal of guanidinosuccinic acid and infusion of calcium during hemodialysis contribute to the raised serum levels of these pepsinogens after hemodialysis.

Comparative study of the effects of different diuretics on the permeability properties of the toad bladder.

Abstract 1. The effects of nine representative diuretics on the short-circuit current and the hydroosmotic response to vasopressin were studied under the same conditions using the toad bladder. 2. On the basis of these effects from either the serosal or the mucosal side, the diuretics examined were classified into five groups. 3. Differences and similarities between the present results and those reported with the toad bladder and amphibian skin were also discussed.

Evaluation of Hemodialysis Efficiency by an Edema Fluid Model

The concentrations of urea, creatinine, and uric acid were measured in edema fluid and plasma during hemodialysis and 18 h after hemodialysis. The concentrations of these solutes in plasma were 15-17% lower than in the edema fluid after hemodialysis. Eighteen hours after hemodialysis, however, the concentrations in plasma were almost the same as those in edema fluid. These data suggest that the removal of these solutes from the extracellular space is delayed during hemodialysis. The plasma concentrations obtained at 18 h after hemodialysis are better indicators of hemodialysis efficiency.

Pharmacokinetics of Denopamine in Hemodialysis Patients

The pharmacokinetics of denopamine on a hemodialysis day and on an interdialysis day was evaluated in 11 hemodialysis patients. Tmax was the only pharmacokinetical parameter that differed significantly between healthy volunteers and hemodialysis patients. It is suggested that denopamine can be administered to hemodialysis both on hemodialysis days and on interdialysis days without dosage adjustments.

Treatment of hemodialysis-induced hypotension with oral droxidopa.

血液透析 (HD) 中の低血圧発作 (HIH) は深刻な合併症である. ドロキシドパ (DOPS) は, 経口投与が可能なnorepinephrine (NE) 前駆アミノ酸で, Shy-Drager症候群などに見られる起立性低血圧に臨床応用されている. 我々はすでに, HD患者においてもDOPSが有効に吸収されNEに変換し, HIHに対して有効例の存在することを報告した. そこで今回, 多施設における初期第II相試験を行い, 用量設定に関しても検討した. 5施設において, 処置を要するHIHを呈した週3回の慢性HD患者34例 (男14例, 糖尿病性腎不全〔DM〕12例) を対象とした. DOPSはHD開始1時間前に200mgから服用させ, 効果に応じて1週毎に100mgずつ, 400mgまで増量し6週継続した. 本試験中透析条件は一定とし, 一定の透析経過記載表を用い, 観察項目, HIHに対する処置を統一した. 全症例の比較でも, 透析中の最低血圧時, 透析終了時, 終了後立位時の血圧がいずれも有意に上昇した. また, HIHに対する補液量, 処置回数も有意に減少した.個々の症例の検討でも, 67.6%に有用性が認められ, 透析中の自覚症状の改善が73.5%に, 透析終了後の改善が64.7%に得られた. 副作用は3例に見られたが, 減量後消失し, DOPSの継続は可能であった. 最終投与量は200mg13例, 300mg7例, 400mg14例で, 400mg群の有用性は200, 300mg群に比べ有意に低値であった. 年齢, 透析期間と有効性には関連はないが, HIHの軽症な患者, HD前収縮期血圧の低い患者に有用率が高い. また, DM患者の有用率は慢性糸球体腎炎患者に比べ有意に低値であったが, 補液量, 処置回数は, 両者とも有意に減少した. HD前NE濃度は有用性と関連が認められなかった. 以上, HIHを呈する慢性HD患者の約2/3の症例にDOPSの有用性を確認した.