Kiyofumi Hirata

Effects of an oral protein load on glomerular filtration rate in healthy controls and nephrotic patients.

Glomerular filtration rate (GFR), effective renal plasma flow (ERPF) and humoral factors were simultaneously examined before and after a 50-gram oral protein load in 12 healthy controls and 12 nephrotic patients. The protein load led to rises in GFR with unchanged filtration fraction in both groups although the rate of increase in GFR was greater in the former. The levels of blood urea nitrogen, serum osmotic pressure, plasma glucagon and serum insulin, but not plasma angiotensin II, were significantly elevated following the protein load. The increase in GFR after the protein load appears to be mainly caused by increased ERPF and afferent arteriolar vasodilation.

Characteristic Changes of the Juxtaglomerular Cells before and after Treatment of Pseudo-Bartter’s Syndrome due to Furosemide Abuse

Histological and ultrastructural studies of juxtaglomerular cells (JGC) were performed in a patient with pseudo-Bartters syndrome due to furosemide abuse. The biopsy done before the treatment revealed a large number of secretory granules and mitochondria, dilated rough endoplasmic reticulum and a well-developed Golgi apparatus in JGC. The JGC granules, some of which contained crystalloid structures showed various shapes and sizes. In the biopsy carried out after the cessation of furosemide intake, these morphological changes were markedly improved with a reduced activity of the renin-angiotensin system. The characteristic changes of JGC may be valuable in determing the functional and morphological interrelations of this disorder.

Immunocytochemical Study of Glutathione Peroxidase in Normal Rat Kidney

In the normal rat kidney, immunohistochemical localization of glutathione peroxidase (GSH-Po) was mainly in the proximal tubules (PTs), where the proximal portions (S1 + S2) were more intensely stained than the distal portion (S3). Immunocytochemically, GSH-Po was localized in cytosol including the core of microvilli and lysosomes of the epithelial cells in the PTs. Since albumin and IgG were not found in cytosol, it is suggested that cytosolic GSH-Po may be generated in situ, but is not derived from the serum.

Immunocytochemical Localization of Glutathione Peroxidase in Uremic Rat Kidney

Lipid peroxidation is the oxidative deterioration of polyunsaturated lipid (1). Glutathione peroxidase (GSH-Po) is the enzlme which catalyzes the reduction of lipid peroxides with the concomitant oxidation of glutathione (2). Previously we reproted that the immunohistochemical localization of GSH-Po was mainly in the proximal tubules, there the proximal portions (S1+S2) were more intensely stained than the distal portion (S3), and the immunocytochemical localization of GSH-Po swas in cytosol, including the core of microvilli and lysosomes of the epithelial cells in proximai tubules (PT) in normal rat kidney (3). This study was designed to investigate the immunocytochemical localization of GSH-Po in the uremic rat kidney in order to clarify the pathophysiological significance of the enzyme.

Peripheral neuropathy and myopathy in long-term hemodialysis patients

25例の長期透析患者において尿毒症性末梢性ニューロパチーおよび尿毒症性ミオパチーを臨床的, 血液生化学的, 電気生理学的および病理学的に検討し, その結果を保存療法患者におけるそれと対比した. 平均透析期間は3年3カ月であり, 保存療法群のCcrは4.1±0.4 (mean±SE) ml/minであった. 透析患者25例中, 神経原性変化は全例(100%), 筋原性変化は6例 (24%) に認められた. 保存療法患者30例中, 神経原性変化は19例 (64%), 筋原性変化は13例 (43%) に認められ, 4例 (13%) には異常が認められなかった.混合性変化は両群で認められた. 末梢運動神経最大伝導速度は透析群において保存群に比し高頻度に低下しており, 有意 (P<0.001～P<0.02) の低値を示した. 結局ミオパチーについては両群間に差異は認められなかったが, 末梢性ニューロパチーは透析群でより高頻度で重篤であった.したがって通常の透析療法による末梢性ニューロパチーの消失は期待し得ないと考えられる.