Effects of ovarian ischemia-reperfusion on luteal function in pregnant rats

An involvement of reactive oxygen species in CL regression has been reported. We have shown that a decrease in serum progesterone concentrations coincides with a decrease in superoxide dismutase (SOD) activities and an increase in lipid peroxide levels in the CL after Day 15 of pregnancy. Recently it has been found that ischemia-reperfusion stimulates reactive oxygen species production and causes tissue damage in various organs. We therefore tested the effect of ischemia-reperfusion in the ovary on CL function in pregnant rats. On Day 15 of pregnancy, after clamping of the bilateral ovarian vessels for 30 min, the ovaries were reperfused for 90 min by declamping. The ischemia-reperfusion decreased serum progesterone concentration and SOD activity in the CL and increased lipid peroxide in the CL 90 min after reperfusion. The effects of ischemia-reperfusion, including the decrease in serum progesterone concentrations, were completely blocked by simultaneous injection of SOD and catalase, but not by indomethacin administration. The present study shows that CL function was inhibited by reactive oxygen species produced by ischemia-reperfusion in the ovary and that the effect was not mediated through prostaglandins.

[Nutritional assessment of patients on continuous ambulatory peritoneal dialysis]

Nutritional status was assessed in 214 CAPD patients from eight centers in Japan. All patients were receiving adequate dialysis, as indicated by KT/Vurea and Karnofsky's activity scale. Subjective global assessment indicated that 25% of 83 female patients and 27% of 131 male patients were, at least, moderately malnourished. Mid-arm muscle circumference was lower in malnourished male patients than in well-nourished patients, however, in female patients none of the anthropometric variables reflected nutritional status. Lower serum albumin level was observed in malnourished male patients, but not in female patients. Daily protein intake, estimated from protein catabolic rate (PCR) was approximately 0.8 g/Kg BW in both males and females. This value is similar to those reported in literatures for CAPD patients. In our well-rehabilitated patients, PCR did not reflect the nutritional status as indicated by subjective global assessment. The data suggest that low protein intake was not always the major cause of malnutrition in these patients and that other factors, such as endocrine disorder, may also have contributed to malnutrition.

A clinical trial of FK506 in refractory uveitis

We performed a clinical open trial to evaluate the efficacy and the adverse side effects of a single therapy with FK506 in refractory uveitis as a multicenter study in Japan. Fifty-three patients (41 patients with Bechçet's disease, five with Vogt-Koyanagi-Harada disease, four with idiopathic retinal vasculitis, and three with other forms of uveitis) were enrolled in the study. FK506 was given orally for 12 weeks. Treatment with FK506 exhibited therapeutic effects in a dosage-dependent manner: the effectiveness was 38% in patients treated with an initial dosage of 0.05 mg/kg of body weight per day, 60% with 0.10 mg/kg of body weight per day, 83% with 0.15 mg/kg of body weight per day, and 79% with 0.20 mg/kg of body weight per day. Overall efficacy with dosage adjustment when needed was 76.5% at the conclusion of the study at the end of the 12th week. The FK506 therapy induced a variety of adverse side effects, the incidence of which depended on the dosage. The major side effects were renal impairment (28.3%, 15 of 53 patients), neurologic symptoms (20.8%, 11 of 53 patients), gastrointestinal symptoms (18.9%, ten of 53 patients), and hyperglycemia (13.2%, seven of 53 patients). The trough level of FK506 in the whole blood correlated with both the efficacy of the therapy and with the incidence of adverse effects. It is recommended to maintain the trough level between 15 and 25 ng/ml. On the basis of these results, a daily dosage of 0.10 to 0.15 mg/kg of body weight per day was suggested as an appropriate therapeutic dosage for refractory uveitis.

[Success of cyclosporine therapy in two patients with PSS]

Two PSS patients, unresponsive to D-penicillamine, steroid, cyclophosphamide and plasma exchange therapy, were treated with cyclosporine. One patient complained scleroderma, dysphagia and dyspnea during movement after treatment with steroid, plasma exchange and cyclophosphamide. He showed a increased Leu3a/2a ratio (6.72). About 3 months after treatment with cyclosporine, these complain decreased with normalization of elevated Leu 3 a/2 a ratio. 1 year after treatment, %DLco increased 86% from 50% and pneumonitis findings of chest X-ray and chest CT were also improved. Another patient who complained Raynaud's phenomenon and scleroderma which had extended over his abdomen despite treatment with steroid and cyclophosphamide. 1 month after treatment with cyclosporine, improvement of these phenomenon were recognized. It is concluded that cyclosporine can be an effective agent in the treatment of PSS.

Changes in activities of superoxide dismutase and lipid peroxide in corpus luteum during pregnancy in rats

Activities of superoxide dismutase (SOD) and lipid peroxide (LPO) were studied in corpora lutea of pregnant rats. SOD activities, both Mn-SOD and Cu,Zn-SOD, gradually increased in the corpora lutea until day 15 of pregnancy and decreased thereafter until day 21 of pregnancy, in a similar manner to serum progesterone concentration. LPO activities remained low until day 15 of pregnancy, but increased rapidly after day 15 to day 21 of pregnancy. Incubation of the dispersed luteal cells from day 15 of pregnancy in vitro showed that FeSO4 and ascorbic acid, which induce lipid peroxidation, significantly inhibited progesterone secretion. The inhibitory effects of FeSO4 and ascorbic acid were blocked by the simultaneous addition of alpha-tocopherol. These results suggest important roles for SOD and LPO in regulating luteal function during pregnancy.

Hereditary serum cholinesterase deficiency associated with severe lipid deposition in the kidney

A 47-year-old woman who was homozygous for a silent cholinesterase gene (hereditary serum cholinesterase deficiency) presented with nephrotic syndrome and hyperlipidemia. Renal biopsy performed in 1986 demonstrated mesangial proliferative glomerulonephritis. Four years later, a second biopsy revealed progression with mesangial interpositions and severe lipid deposition in the glomeruli, tubules and interstitium. This is the first case of hereditary serum cholinesterase deficiency accompanied by renal disease. Serum cholinesterase deficiency may be related to hyperlipidemia and abnormal lipid deposition in the kidney, which promotes the progression of renal disease.

Endothelin-specific antibodies decrease blood pressure and increase glomerular filtration rate and renal plasma flow in spontaneously hypertensive rats

OBJECTIVE

Studies were undertaken to clarify the pathophysiologic significance of endogenous endothelin in the control of blood pressure and renal hemodynamics in spontaneously hypertensive rats (SHR).

DESIGN

The technique of passive immunization was used to neutralize endogenous endothelin in order to estimate the contribution of endothelin to the in vivo control of blood pressure and renal hemodynamics.

METHODS

Endothelin-specific antibodies were administered intravenously into anesthetized SHR and Wistar-Kyoto (WKY) rats, and the effects upon blood pressure and renal function (renal plasma flow and glomerular filtration rate) assessed. Using the same antibodies, baseline plasma levels of endothelin in both strains of rats were determined by radioimmunoassay.

RESULTS

Infusion of endothelin-specific antibodies into SHR decreased mean arterial pressure by approximately 10% and renal vascular resistance and renal vascular resistance by approximately 35%. Glomerular filtration rate and renal plasma flow both increased by approximately 50% over control. In contrast, infusion of normal rabbit serum into SHR or of endothelin-specific antibodies into WKY rats did not result in any significant change in renal hemodynamics or arterial blood pressure. Baseline plasma levels of immunoreactive endothelin in SHR were significantly lower than those in WKY rats.

CONCLUSION

These results suggest that endothelin plays an important role in the modulation of systemic blood pressure and renal function in SHR.

[Increased serum levels of human cardiac myosin light chain 1 in patients with renal failure]

In this study, we measured cMLC1 concentration in serum and urine from patients with acute myocardial infarction (AMI), chronic renal failure (CRF), and various grades of renal dysfunction (RD) in comparison with normal controls, by using enzyme immunoassay (EIA) with monoclonal antibody, and attempted to elucidate the mechanism of increased serum level of cMLC1 in patients with renal failure. The serum level of cMLC1 of CRF patients under maintenance hemodialysis (HD) was 20.3 +/- 19.6 ng/ml, markedly higher than normal controls (0.54 +/- 0.55 ng/ml). The patients with RD and CRF under conservative therapy had higher serum cMLC1 level than normal controls especially in advanced CRF, while each value not correlating with their creatine clearance (Ccr). cMLC1 in urine was detectable in only two cases with AMI accompanied with CRF or RD. In addition, immunohistological studies of renal biopsy specimens from RD patients did not show cMLC1 deposits in glomerulus. These results suggest that cMLC1 is assumably filtered through the glomerulus, and then absorbed in the renal tubule.

Comparison of converting enzyme inhibitor and calcium channel blocker in SHR with nephrotoxic serum nephritis

In order to compare the protective effects of angiotensin converting enzyme inhibitors (ACEI) and calcium channel blockers (CCB) on the renal function in experimental nephritis, nephrotoxic serum nephritis was induced in male spontaneously hypertensive rats (SHR). The above drugs were then chronically administered to different groups, as follows: the ACEI-treated group (n = 7) received captopril (150 mg/kg/day), and the CCB-treated group (n = 6) was given both nifedipine (40 mg/kg/day) and nisoldipine (20 mg/kg/day). The control group (n = 8) received a placebo. Although the control group developed marked hypertension and proteinuria, the rats treated with either ACEI or CCB demonstrated a significant and equivalent decrease in mean arterial pressure and urinary protein excretion. At 15 weeks after the injection of nephrotoxic serum, all rats were anesthetized with Inactin, and the glomerular filtration rate (GFR) and renal plasma flow (RPF) were measured. In the control group, GFR and RPF were markedly attenuated. However, both were preserved at much higher levels in the ACEI-treated group, and GFR was also maintained to a similar degree in the CCB-treated group. Histological studies were carried out after the clearance studies. As a result, it was found that the ACEI treatment significantly limited the development of glomerulosclerosis, whereas CCB modestly ameliorated the glomerular structural lesions. Moreover, ACEI significantly reduced the serum cholesterol, while CCB did not exert such an effect. These results suggest that both ACEI and CCB have a therapeutic effect in experimental glomerulonephritis models which are accompanied by hypertension.(ABSTRACT TRUNCATED AT 250 WORDS)

[Improvement of malnutrition indices in adult patients with end stage renal disease by recombinant human growth hormone]

Recombinant human growth hormone (r-hGH), 1 U/kg body weight/week, was administered subcutaneously for 2-4 weeks to two end stage renal disease patients with severe malnutrition. Following r-hGH, there were significant increase in hematocrit level and serum concentration of albumin, IGF-1 and GH, and decrease of urea nitrogen. It was concluded that r-hGH exerts a therapeutic effect to nutritional status in renal failure patients by improving severe hypoalbuminemia, susceptibility to infectious disease, intractable ascites and so on.

Effect of dietary chloride on spontaneously hypertensive rat

The anionic component of sodium salt has been reported to contribute to hypertension in some animal models and hypertensive patients. In the present study, the anionic effects on exacerbation of hypertension in spontaneously hypertensive rat (SHR) were investigated by chronic loading tests with two sources of sodium, viz. sodium chloride (NaCl; 0.9% solution) and sodium bicarbonate (NaHCO3; 1.28% solution), using SHRs with normal renal function (NRF) and with chronic renal failure (CRF; produced by cryosurgery). In addition, extracellular fluid volume (ECFV: inulin space) was measured in SHRs with NRF and CRF. In the NRF groups, systolic blood pressure (SBP) reached 230 mmHg at Week 13, and there was no significant difference in SBP between the NaCl and NaHCO3 groups. In the CRF groups, SBP of the NaCl group was significantly higher (p less than 0.01) than that of the NaHCO3 group (280 mmHg vs. 230 mmHg at Week 15). ECFV was also greater in the NaCl group than in the NaHCO3 group (ECFV: NaCl vs. NaHCO3, 15.9 +/- 1.7 vs. 14.0 +/- 0.9 at Week 13; and 16.2 +/- 1.1 vs. 14.2 +/- 1.2 at Week 15, respectively). These results indicate that chloride ion plays an important role in the pathogenesis of hypertension in SHR with CRF. Expansion of ECFV is considered to be one of the mechanisms whereby the hypertension is exacerbated.

Tubuloglomerular feedback resetting in different models of acute volume expansion

Our results revealed that renal blood flow (RBF) increased during both isooncotic and hypooncotic plasma expansion by 4% of body weight (BW). Tubuloglomerular feedback (TGF) sensitivity assessed by the measurement of proximal stop-flow pressure at loop perfusion rates of 0 to 40 nl/min and RBF autoregulation were not substantially affected by this degree of volume expansion, provided plasma oncotic pressure did not change. This upward shift of the TGF response curve together with maintenance of an RBF autoregulation during plasma expansion lead to the conclusion that the TGF mechanism apparently plays a significant role in the control of glomerular hemodynamics, despite the marked vasodilation occurring during acute volume expansion.

Different mechanisms for the inhibition of progesterone secretion by ACTH and corticosterone in pregnant rats

The present study investigated possible sites through which ACTH or corticosterone inhibit progesterone secretion in pregnant rats, and the role of placental factors in blocking the inhibitory effect. The number of conceptuses was adjusted to one (IC group) or more than ten (FC group) on day 7 of pregnancy by aspirating the desired number. Serum concentrations of progesterone, testosterone and oestradiol were significantly (P less than 0.01) lower on day 15 in the 1C group than in the FC group. Corpora lutea (CL) obtained on day 15 were incubated for 6 h with corticosterone or ACTH. Corticosterone (1 mumol/l) significantly (P less than 0.05) inhibited progesterone secretion in the 1C group but not in the FC group. The inhibitory effect of corticosterone in the 1C group was completely blocked by co-addition of 1 mumol testosterone/l or 1 mumol oestradiol/l but not by 1 mumol dihydrotestosterone/l. ACTH (1 microgram/l-1 mg/l) had no direct effect on progesterone secretion in either the 1C or the FC groups, although ACTH apparently decreases progesterone secretion in vivo. Placentae obtained from rats of the FC group on day 15 were incubated for 24 h with or without ACTH (1 mg/l). The supernatant after placental incubation without ACTH significantly (P less than 0.01) increased progesterone secretion by the CL in both the 1C and FC groups, and also eliminated the inhibitory effect of corticosterone in the 1C group. The supernatant after placental incubation with ACTH also increased progesterone secretion in the FC group as effectively as the supernatant from the control incubation, but it had no effect in the 1C group.(ABSTRACT TRUNCATED AT 250 WORDS)

Molecular form of immunoreactive endothelin in plasma and urine of normal subjects and patients with various disease states

To elucidate the pathophysiologic significance of the family of endothelin (ET) peptides, we have investigated plasma and urinary immunoreactive (ir-) ET levels and its molecular forms in normal and pathological conditions. Plasma and urine ET were extracted with an Amprep C2 column. The molecular form of ET was determined by a combination of radioimmunoassay and reverse-phase high-performance liquid chromatography. Although plasma ir-ET was composed mainly of big ET and endothelin-1 (ET-1) in normal subjects, that in acute myocardial infarction, chronic renal failure (CRF), essential hypertension, and vasospastic angina pectoris was characterized by an increase of high molecular ir-ET in addition to increases in big ET and ET-1. Urinary ir-ET in both normal subjects and patients with CRF was composed mainly of a high molecular form in addition to big ET and ET-1. These results suggest that the biosynthetic and/or degradation process of ET under pathological conditions appears to be different from that under normal conditions.