Rhythmical contractions in pulmonary arteries of monocrotaline-induced pulmonary hypertensive rats

Rhythmical contractions accompanied by an increase in cytosolic Ca2+ concentrations were produced in ring preparations of endothelium-denuded pulmonary arteries from monocrotaline-treated rats, but not in those from vehicle-treated rats, 2-3 h after a resting tension of 15 mN (150-180% of the initial wall length of the artery) was applied. The rhythmical contractions were abolished by nicardipine and ryanodine. Cyclopiazonic acid reduced the relaxation phase of the rhythmical contractions, finally leading to a sustained contraction. Similarly, apamin caused a sustained contraction, whereas charybdotoxin increased the amplitude of the rhythmical contractions. Glibenclamide had no apparent effects on them. Indomethacin and the prostaglandin H2/thromboxane A2 receptor antagonist SQ29548 abolished the rhythmical contractions and reduced the tension, but the thromboxane synthase inhibitor ozagrel had no effect. These results suggest that optimal stretch induces rhythmical contractions in the pulmonary arteries of monocrotaline-induced pulmonary hypertensive rats, to which both Ca2+ influx through voltage-operated Ca2+ channels and Ca2+ release from the endoplasmic reticulum seem to contribute. It is also suggested that small-conductance Ca(2+)-activated K+ channels participate in the relaxation phase of rhythmical contractions. Furthermore, prostaglandin H2 released from nonendothelial cells is likely to play a pivotal role in the induction of rhythmical contractions.     

Protodioscin isolated from fenugreek (Trigonella foenumgraecum L.) induces cell death and morphological change indicative of apoptosis in leukemic cell line H-60, but not in gastric cancer cell line KATO III

Protodioscin (PD) was purified from fenugreek (Trigonella foenumgraecum L.) and identified by Mass, and 1H- and 13C-NMR. The effects of PD on cell viability in human leukemia HL-60 and human stomach cancer KATO III cells were investigated. PD displayed strong growth inhibitory effect against HL-60 cells, but weak growth inhibitory effect on KATO III cells. Morphological change showing apoptotic bodies was observed in the HL-60 cells treated with PD, but not in KATO III cells treated with PD. Flow cytometric analysis showed that the hypodiploid nuclei of HL-60 cells were increased to 75.2, 96.3, and 100% after a 3-day treatment with 2.5, 5, and 10 microM PD, respectively. The fragmentation by PD of DNA to oligonucleosomal-sized fragments, that is a characteristic of apoptosis, was observed to be both concentration- and time-dependent in the HL-60 cells. These findings suggest that growth inhibition by PD of HL-60 cells results from the induction of apoptosis by this compound in HL-60 cells.     

A stereomicroscopic study of the mastopathic human breast

Summary The stereomicroscopic study of cystic disease of the breast revealed the presence of abnormal ductules near the terminal sites of the original lactiferous ducts. This alteration was the key feature of cystic disease since the involution of abnormal ductules possibly may have induced the stricture of the original duct by increasing fibrosis around the site of duct evolution. The phenomenon could contribute to the creation of cystic dilatation of distal ducts and acini. Multiple large cysts characterizing the morphology of cystic disease may represent the end stage of distended ducts and acini. Prolonged and repeated unbalanced stimulation of hormones could produce progressive and regressive alternations in the same breast. This modifies the original alteration into more pleomorphic and complicated types.

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Stereomikroskopische Studie der durch Mastopathie veränderten menschlichen MammaII. Die peripherische Form der Milchgangsevolution und ihre Beziehung zur Cystenmamma

Zusammenfassung Die stereomikroskopische Untersuchung sog. Cystenmmamen zeigt, daß die Cysten durch Ektasie der sog. Kanälchen-Endäste entstehen. Dagegen werden die Stamm-Milchgänge einer Involution zugeführt. An der Cystenbildung beteiligen sich auch die Acini. Als morphogenetische Reize kommen hormonelle Dysregulatonen in Frage. Durch die unterschiedliche Ausbildung der Kanälchen proliferation einerseits, die Involution sowie Cystenbildung andererseits resultiert ein buntes, wenig einheitliches Bild.

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Clinical Investigator, Veterans Administration Hospital, San Francisco, California, U.S.A., Former Postgraduate Student, Faculty of Medicine, Tokyo Medical and Dental University, Japan.

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This investigation was carried out at the Department of Pathology, Faculty of Medicine, Tokyo Medical and Dental University from 1958 to 1960 and was partially supported by a special research grant of the Japanese Ministry of Education.     

A toxic substance from the sea urchinToxopneustes pileolus induces histamine release from rat peritoneal mast cells

A toxic substance (P-II fraction), fractionated from the pedicellariae of the sea urchinToxopneustes pileulus, dose-dependently caused the histamine release from rat peritoneal mast cells. The histamine release induced by P-II fraction increased with time, while compound 48/80 caused a more rapid histamine release. The dose-response curve for P-II fraction was studied with concentration 0.03–2.0 mg/ml. This reaction was dependent on Ca²⁺ and temperature. When glucose (5.5. mM) was omitted during the incubation step, the histamine release induced by P-II fraction was significantly reduced as compared to that of compound 48/80. Pyruvate reversed this reduction. On the other hand, the histamine release induced by P-II fraction was effectively potentiated by the addition of glucose (11.0 mM), but not that by compound 48/80. These results suggest that P-II fraction-induced histamine release differs from that of compound 48/80 disregards to the effects of glucose, because this histamine release appears to be more sensitive to the glycolytic pathway than compound 48/80-induced histamine release.     

Human cytomegalovirus infection in foci of Langerhans cell histiocytosis

 Langerhans cell histiocytosis (LCH) has been thought to be a disorder of immune regulation, and increasingly, evidence showing that the tissue damage in LCH involves lymphokines and pro-inflammatory cytokines is reported. We detected human cytomegalovirus (HCMV)-DNA in LCH cells in the foci of LCH lesions by immunohistochemistry, in situ hybridization and PCR. HCMV was detected in the nuclei and/or cytoplasm of LCH cells in 9 of 27 LCH cases by immunostaining. HCMV was probably an early antigen. In situ hybridization revealed signals for HCMV-DNA only in the nuclei of LCH cells in 10 of the 27 LCH cases. PCR analysis was performed in 20 of the LCH cases, and HCMV-DNA was detected in 7 of these. All 7 positive cases were also positive for HCMV by ISH and IHC. These findings suggested that early phase infection or reactivation of HCMV occurred in the LCH lesions. HCMV infection may be accompanied by impaired cytokine production. Our study also suggested a relationship between HCMV infection and expression of TNFα. In tissues affected by LCH, dermatopathic lymphadenopathy or malignant fibrous histiocytoma and in normal tissues no signals for Epstein-Barr virus-RNA were detected. These findings suggest that in some cases LCH is associated with HCMV infection. Received: 24 November 1998 / Accepted: 24 April 1998     

Abnormal distribution of cathepsin proteinases and endogenous inhibitors (cystatins) in the hippocampus of patients with Alzheimer's disease,parkinsonism-dementia complex on Guam,and senile dementia and in the aged

The immunolocalization of cathepsins B(CB), H and L and cystatins(C) and(C) were examined in the hippocampus of cases of sporadic Alzheimer's disease (12 cases), parkinsonism-dementia complex on Guam (eight cases), senile dementia of Alzheimer type (two cases), aged subjects with marked senile change (one case) and controls (12 cases, including six normal subjects). CB was lower in most nerve cells in patients than in controls, but markedly increased at the sites of intracellular neurofibrillary tangles (NFTs) and degenerative neurites and/or dendrites in and outside senile plaques (SPs), indicating its close involvement in the metabolisms of various proteins in NFT and SPs. Abundant C and C were demonstrated in SP amyloid, suggesting that they are amyloid constituents or co-exist with amyloid. The present study indicated that CB, C and C are closely involved in abnormal protein metabolism in NFTs and SP amyloid and suggested that degeneration or denaturation of intracellular proteins, including substrates for proteases and lysosomes, from some acquired cause, results in absolute and/or relative overload for these proteolytic systems, including their inhibitors. This results in incomplete and/or abnormal proteolysis related to NFT and/or amyloid formation.     

Relationship between core temperature and skin blood flux in lower limbs during prolonged arm exercise in persons with spinal cord injury

The purposes of the present study were to examine the response of the skin blood flux (SBF) in the paralyzed lower limbs of persons with spinal cord injury (PSCI) and to clarify the relationship between the SBF and core temperature during prolonged arm exercise. Eight male PSCI with lesions from T6 to L5 and six male control subjects (CS) participated in this study. The subjects rested for 60 min and then performed arm-cranking exercise at 20 W for 30 min at 25 °C. The tympanic membrane temperature (T _ty) and SBF in the anterior thigh (SBFT) and in the posterior calf (SBFC) were continuously measured throughout the experiment. The SBFC did not change in either PSCI or CS during the experiment. The SBFT in four PSCI with high lesions (T6 to T12), remained unchanged during exercise. The SBFT in the other four PSCI with low lesions (T12 to L5, SBFT+) began to elevate markedly when the T t, exceeded a threshold temperature of 36.69 °C. The pattern of increase of SBFT in SBFT+ was similar to that in CS, although onset of the increase in SBFT was delayed and the peak of SBFT during exercise was significantly lower in comparison with the CS. We consider that these differences between the SBFT+ and CS were largely attributable to the lowerT _ty in the former group, which took a prolonged time to reach the threshold of 36.69 °C.     

Effects of hypoxia and tumor necrosis factor-alpha on production of plasminogen activator inhibitor-1 in human proximal renal tubular cells

Chronic hypoxia has been newly proposed as a common mechanism of tubulointerstitial fibrosis in the progression of various chronic inflammatory renal diseases, where PAI-1 plays an important role in the accumulation of extracellular matrix (ECM) through inhibition of plasmin-dependent ECM degradation. In the present study, we investigated the presence of PAI-1 in renal tubular cells by immunostaining renal biopsy samples. We also closely examined the effects of hypoxia and TNF-alpha on PAI-1 expression in cultured human proximal renal tubular cells (HRCs). Confluent cells growth-arrested in DMEM for 24h were exposed to hypoxia (1% O2) and/or TNF-alpha at 10 ng/ml for 24 hours. Amounts of PAI-1 protein and mRNA after stimulation were measured by ELISA and TaqMan quantitative PCR, respectively and compared to those in cells incubated under control conditions (18% O2 without TNF-alpha). HIF-1alpha was demonstrated by immunoblot analysis. In crescentic glomerulonephritis, clusters of proximal tubules were specifically stained for PAI-1. Treatment of 24 hours with hypoxia, TNF-alpha and their combination induced a 2.7-fold, a 1.8-fold, and a 4.6-fold increase in PAI-1 protein secretion, and produced a 3.6-fold, a 3.3-fold, and a 12.1-fold increase at the PAI-1 mRNA level, respectively. Immunoblot analysis revealed that hypoxia-inducible factor-1alpha (HIF-1alpha) was markedly accumulated in the nuclear fraction after 16-hours exposure of HPTECs to hypoxia but not to TNF-alpha. In conclusion, hypoxia induces PAI-1 expression via remarkable nuclear accumulation of HIF-1alpha in HRCs. TNF-alpha can enhance this hypoxia-induced PAI-1 expression.     

Rat strain differences in the early stage of porcine-serum-induced hepatic fibrosis.

Rat strain differences in the early development of porcine serum (PS)-induced hepatic fibrosis were histologically and immunohistochemically examined using Brown Norway (BN), Sprague Dawley (SD) and Wistar rats. They were injected i.p. with 0.5 ml sterile PS twice a week for 4 and 8 weeks. In addition, rats treated with physiological saline in the same way served as controls. At 4 weeks, hepatic fibrosis accompanying fibrous septa mainly composed of type III collagens developed in BN and SD rats but not in Wistar rats. In addition, the numbers of eosinophils, CD3-positive cells and ED-1-positive cells significantly increased in BN and SD rats, that of CD45RA-positive cells in BN rats, and that of alpha-smooth muscle actin (SMA)-positive cells in SD rats, respectively. Such differences in the number of inflammatory cells may be related with the absence of hepatic fibrosis in Wistar rats at 4 weeks. At 8 weeks, hepatic fibrosis with formation of many small-sized pseudolobules was observed in all strains at almost similar degree, and the numbers of infiltrating cells increased in all strains of rats with some exception. In addition, the main location of inflammatory cells was different, suggesting a different role of each inflammatory cell in the process of hepatic fibrosis.