Comparison of eicosapentaenoic acid concentrations in plasma between patients with ischemic stroke and control subjects.

Objective: ω-3 fatty acids, including eicosapentaenoic acid (EPA), prevent ischemic stroke. However, the clinical importance of EPA for ischemic stroke and its subtype has not been fully elucidated.

Methods: In a cross-sectional study, we determined whether ω-3 fatty acids were predictive factors for ischemic stroke.

Expression and localization of the water channels in human autosomal dominant polycystic kidney disease.

To characterize the cyst-lining cells in human autosomal dominant polycystic kidney disease (ADPKD), we performed immunohistological studies with specific antibodies against human aquaporin-2 (AQP-2, the vasopressin-regulated water channel) and aquaporin-3 (AQP-3), which are expressed only in collecting duct cells in the normal kidney. The polycystic kidney samples were obtained from 2 hemodialysis patient at uninephrectomy. Immunohistochemical studies revealed two types of staining of cyst-lining cells.

Role of vasopressin V2 receptor in acute regulation of aquaporin-2.

Aquaporin-2 (AQP-2) has been shown to be a vasopressin-sensitive water channel in collecting duct (CD) cells of the kidney. To prove the role of the vasopressin V2 receptor (V2R) in the regulation of intracellular AQP-2 shuttling, we examined the acute effects of vasopressin and V2R antagonist on the distribution of AQP-2 in the cells. Normal Wistar rats were given continuous infusions of vasopressin, vasopressin V2R antagonist (OPC31260), or both.

Expression and distribution of aquaporin of collecting duct are regulated by vasopressin V2 receptor in rat kidney.

To examine whether expression and distribution of aquaporin of collecting duct (AQP-CD) are regulated by vasopressin V2 receptor (V2R), we performed immunohistochemical studies with specific antibody against AQP-CD. Normal Wistar rats were divided into four groups and treated for 3 d; control, dehydration, vasopressin V1 receptor (V1R) antagonist (OPC-21268 120 mg/kg), V2R antagonist (OPC-31260 30 mg/kg). At time of death, urine osmolality (Uosm) in the dehydration group (1884 +/- 245 mOsm/kg) was significantly higher than that in the control (938 +/- 91).

Chronic DOC treatment enhances Na(+)-H+ exchanger activity of beta-intercalated cells in rabbit CCD.

Chronic deoxycorticosterone (DOC) treatment is known to increase HCO3- secretion in rabbit cortical collecting ducts (CCD). In this study, we examined whether changes in number or function of intercalated cells (ICC) are induced by DOC treatment. The number of total ICC [acetoxymethyl ester of 2',7'-bis(2-carboxyethyl)-5(6)-carboxyfluorescein (BCECF/AM)-positive cells after its luminal loading], and beta-ICC (peanut agglutinin-positive cells) was not different between DOC and control groups in either initial CCD or terminal CCD.

Pharmacokinetics and efficacy of carvedilol in hypertensive patients with chronic renal failure and hemodialysis patients.

The efficacy, safety, and pharmacokinetics of carvedilol were investigated in an open trial performed on 13 hypertensive patients with chronic renal failure and six additional patients requiring hemodialysis. In hypertensive renal failure patients, treatment with carvedilol (5 mg/day) for 1 week produced a significant decrease in blood pressure (from 172/101 to 146/84 mm Hg) but did not change the heart rate. The pharmacokinetics of carvedilol did not change with repeated administration, and there was no accumulation of this drug.

Effects of high salt intake on dopamine production in rat kidney.

To examine the origin of increased urinary dopamine excretion (UDAV) during high salt intake, we measured UDAV from the innervated (INN) or the chronically denervated (DEN) kidney in rats fed either a high-salt (HS) or low-salt (LS) diet. UDAV of DEN [3.50 +/- 0.

Effect of isoproterenol on intracellular pH of the intercalated cells in the rabbit cortical collecting ducts.

To examine the mechanisms which regulate the functions of the intercalated cells (ICs) in the cortical collecting duct (CCD), the effect of isoproterenol on intracellular pH (pHi) of ICs was studied with the in vitro microperfused rabbit CCD, using the single cell pHi determination technique with fluorescent dye, 2',7'-bis-(2-carboxyethyl)-5(and-6)carboxyfluorescein. The pHi of beta-IC was significantly decreased with the addition of basolateral 10(-6) M isoproterenol (7.21 +/- 0.

Aromatic L-amino acid decarboxylase activity along the rat nephron.

Extraneural dopamine is thought to be synthesized by an aromatic L-amino acid decarboxylase (L-AADC) activity in tubular cells. However, the previous histochemical studies of this enzyme's localization in the nephron were not consistent. To determine the localization of L-AADC and whether changes in Na intake regulate this enzyme, L-AADC was measured in microdissected nephron segments from rat kidneys.

[A case of localized amyloidosis of the bladder manifesting post-renal failure].

We report a case of primary localized amyloidosis of the bladder which manifested post-renal failure. A 79-year-old woman with diabetes mellitus complained of anorexia and oliguria. Computed tomographic (CT) scan showed bilateral hydronephrosis.

Aldosterone responses to angiotensin II, adrenocorticotropin, and potassium in chronic experimental diabetes mellitus in rats.

To investigate alterations in aldosterone secretion in diabetes mellitus, the effects of angiotensin II, ACTH, and potassium on aldosterone secretion were examined in conscious unrestrained streptozotocin-induced diabetic rats (60 mg/kg, 12 weeks before study). In chronic experimental diabetic rats where PRA, plasma aldosterone concentration, and urinary excretion of prostaglandin E2 were significantly decreased, a significant attenuated response of aldosterone secretion was demonstrated after infusion of angiotensin II, ACTH, or potassium. Yet the plasma fluorogenic corticosteroids response to ACTH in diabetic rats was not significantly different from that in control rats.

Potassium homeostasis in chronic experimental diabetes mellitus in rats.

To examine potassium homeostasis in diabetes mellitus, we observed the effect of dietary potassium loading on the renin-angiotensin-aldosterone system and potassium balance in streptozotocin-induced diabetic rats. In diabetic rats with 26.51 +/- 1.

Effect of aging on single nephron renin content in rats.

To investigate the relation between renin content in each juxtaglomerular apparatus and reduction of plasma renin activity (PRA) with aging, the PRA and microdissected superficial or juxtamedullary single nephron renin content (SNRC) were determined in 5 young (3-6 months) and 5 aged (13-18 months) rats fed on a normal salt diet. The mean value of the PRA in the aged group was significantly lower than that of the young group. A highly significant correlation was found between the RPA and mean values of the superficial SNRC.

Renin and aldosterone in hypothyroidism: relation to excretion of sodium and potassium.

Changes in plasma renin activity (PRA) and plasma aldosterone (PA) were studied together with the urinary excretion of sodium and potassium in patients with hypothyroidism. The basal levels of PRA and PA were significantly less than those in normal subjects. However, there was no significant relationship between PRA and PA.

Hypertension induced by adrenocortical dysfunction--hypertension in 17 alpha-hydroxylase deficiency and metopirone-induced hypertension.

Hypertension in 17 alpha-hydroxylase deficiency was studied by comparing it with hypertension in Cushing syndrome or that in primary aldosteronism. Furthermore, the role of endogenous increases of ACTH, deoxycorticosterone, and 18 alpha-hydroxy-deoxycorticosterone upon blood pressure was studied in rats by administerating metopirone. Hypertension in 17 alpha-hydroxylase deficiency was considered to be more similar to that in primary aldosteronism from the studies on renin components, pressor responses to angiotensin II and norepinephrine, and renin responses to stimulations.

A case of secondary aldosteronism induced by pheochromocytoma.

A case of secondary aldosteronism caused by a pheochromocytoma containing a large amount of norepinephrine is described. The increased level of angiotensin induced by norepinephrine seems to play an important role in the development of secondary aldosteronism.