Concomitant expression of receptor subtype and isopeptide of endothelin by human adrenal gland.

We studied whether specific receptors for endothelin (ET) isopeptide exist in human aldosterone-producing adenoma and normal adrenal cortex, and whether ET isopeptides are produced by human adrenal gland. Competitive binding studies using [125I]ET-1 as a radioligand revealed the presence of a single class of high-affinity binding sites for ET-1 with the apparent KD of 70 +/- 31 pM and Bmax of 226 +/- 139 fmol/mg protein in adenoma membranes almost comparable to those in adjacent normal cortex. The apparent Ki for ET-2 and ET-3 were 89 +/- 33 pM and 82 +/- 16 pM, respectively.

Regulation of endothelin-1 production in cultured rat mesangial cells.

We investigated the regulatory mechanisms of endothelin (ET)-1 production in cultured rat mesangial cells (MC), with a special focus on the roles of protein kinase A (PKA)- and protein kinase C (PKC)-mediated signaling systems. Vasoactive agents and growth promoting factors, including platelet-derived growth factor, vasopressin and thrombin, which act through receptors coupled to the phospholipase C-mediated signaling system, as well as phorbol ester and fetal calf serum stimulated ET-1 production. This effect was attenuated in PKC-depleted or H-7 (a PKC inhibitor) treated MC.

Hepatocyte growth factor is a paracrine factor for renal epithelial cells: stimulation of DNA synthesis and NA,K-ATPase activity.

The expressions of mRNAs of hepatocyte growth factor (HGF) and its receptor (c-met) and its effects were examined in cultured renal epithelial cell lines (OK, LLCPK1, and MDCK cells) and rat mesangial cells in primary culture. Northern blot analysis revealed the presence of HGF mRNA in mesangial cells, but not in epithelial cells. c-met mRNA was detected in epithelial cells, but not in mesangial cells.

Effects of three distinct natriuretic peptides on receptor binding and guanylate cyclase activities in rat glioma cells.

Receptor binding and cyclic GMP generation by three distinct natriuretic peptides (ANP, BNP, CNP) were studied in a cultured rat glioma cell line (C6). Binding studies revealed the presence of high-affinity binding sites for three natriuretic peptides with almost comparable affinities. In contrast, CNP and BNP were almost equipotent in stimulating intracellular cyclic GMP generation over the low concentration range, but CNP caused further elevation in the high concentration range, whereas ANP was minimally effective.

Significance of plasma glutathione determination in patients with alcoholic and non-alcoholic liver disease.

Plasma glutathione levels were determined in 79 patients with various types of liver disease and 18 healthy controls in order to study their significance in the course of liver disease. Plasma was taken at the time of needle liver biopsy. A positive linear correlation was found between plasma and hepatic glutathione concentrations, as has been suggested in experimental animals.

A partial defect in technetium-99m pyrophosphate image suggesting cardiac rupture following acute myocardial infarction.

We present the case of a 70-year-old woman with acute myocardial infarction who died of cardiac rupture on the 2nd hospital day. Dual isotope single photon emission computed tomography (SPECT) using thallium-201 chloride and technetium-99m pyrophosphate (PYP) performed on the 2nd hospital day showed a large perfusion defect in the anteroseptal wall on 201Tl image and a increased accumulation on 99mTc-PYP image in the anterior area consistent with a partial defect. Autopsy performed 1 h after death revealed a tear in the left ventricular anterior wall consistent with the defect on the 99mTc-PYP image.

Degradation and distribution of brain natriuretic peptide in porcine tissues.

Brain natriuretic peptide (BNP) is a novel peptide that has actions similar to atrial natriuretic peptide (ANP). The present study investigated BNP localization in the heart, ANP and BNP contents in several organs, and ANP and BNP clearance through these organs. In the morphological study, it was shown that porcine BNP-like immunoreactivity was mainly distributed in the granules of the atrium.

Changes of circulating atrial natriuretic peptide and antidiuretic hormone in obstructive sleep apnea syndrome.

Patients with obstructive sleep apnea (OSA) syndrome are known to exhibit nocturnal natriuresis/diuresis. We studied plasma and urinary levels of atrial natriuretic peptide (ANP), a potent natriuretic hormone released from the heart, and plasma antidiuretic hormone (ADH) levels in patients with OSA during awake and sleeping periods, to compare with those of normal subjects. Seven patients with OSA and 6 normal subjects were studied.

Effect of long-term carvedilol therapy on renal function in essential hypertension.

We assessed the long-term effects of carvedilol on renal function in 10 patients with mild-to-moderate essential hypertension. After a 2- to 4-week placebo run-in period, all patients received 5 mg carvedilol once daily. If the effect was insufficient, the dosage was successively increased to 10 or 20 mg once daily.

Possible involvement of protein kinase C and calcium in GSH efflux from Hep G2 cells.

We investigated the effects of protein kinase C modulations and calcium mobilization on GSH efflux in Hep G2 cells. GSH efflux from Hep G2 cells was increased by a phorbol ester. Staurosporine, an inhibitor of protein kinase C, diminished phorbol ester-stimulated GSH efflux from the cells.

V1-receptor mediated GSH efflux by vasopressin from rat hepatocytes.

Vasopression increases sinusoidal efflux of GSH in the perfused rat liver. The mechanism of this effect was studied in the perfused rat liver and in isolated rat hepatocytes. Vasopressin stimulated GSH efflux in both systems and a V1-receptor antagonist (OPC-21268) significantly inhibited the effect of vasopressin suggesting that vasopressin stimulates GSH efflux from rat hepatocytes via V1-receptor.

Structure of the bovine endothelin-B receptor gene and its tissue-specific expression revealed by northern analysis.

We have isolated and characterized the gene encoding the bovine endothelin (ET) receptor ETB with seven putative membrane-spanning domains. The gene exists as a single copy of the bovine genome and extends over 36 kilobases. The coding region is divided into seven exons separated by six introns; the first exon encodes the first and second transmembrane domains and each of the following transmembrane domains is encoded by a separate exon.

[The assessment of cortical and spongy bone mineral content with quantitative computed tomography. A comparison of measurement sites in relation to certain diseases with metabolic bone disorder].

The CT numbers of cortex at the level of 20 cm (CT20) and spongiosa in the lateral condyle at the level of 2 cm (CT20) proximal from the distal end of the femur, and the bone mineral density of spongiosa in the L3 body (BMD), were obtained by QCT. The study included 43 female patients with rheumatoid arthritis (RA), 71 female patients with primary osteoporosis (OP), 20 female nondialyzed patients with chronic renal failure (CRF:nonHD), 37 hemodialyzed patients (CRF:HD), including 13 parathyroidectomized patients (CRF:HD, PTX), and 10 healthy volunteers. CT20 correlated closely with age in RA.

Endothelin-1 inhibits AVP-stimulated osmotic water permeability in rat inner medullary collecting duct.

Endothelin causes diuresis despite an accompanying decrease in glomerular filtration rate and renal plasma flow. Binding sites for endothelin are located not only in glomeruli but also in the inner medulla, possibly in inner medullary collecting ducts (IMCD). To determine whether endothelin has a direct tubular effect, effects of endothelin on water and urea transport were investigated using isolated microperfusion of rat IMCD segments in vitro.

[Postoperative changes in immunoreactive plasma endothelin concentrations].

We investigated postoperative changes in immunoreactive plasma endothelin (ET-1) concentrations using a highly specific and sensitive radioimmunoassay developed for this purpose. The patients were divided into two groups: 10 patients underwent subtotal-esophagectomy by combined right thoracotomy and celiotomy (EC-group), and an other 10 underwent total gastrectomy via celiotomy only (GC-group). Before operation, plasma ET concentrations in both groups were within the normal range.

[Interleukin-2 (IL-2) in active pulmonary tuberculosis].

To clarify the precise of cellular immunity mechanism in pulmonary tuberculosis, we investigated the amount of IL-2 in patients with untreated active pulmonary tuberculosis. When serum adenosine deaminase (ADA) activity was examined using enzyme assay, an abnormally high level was observed in all patients (29.0 + 11.