Generation of new intercellular junctions between cardiocytes. A possible mechanism compensating for mechanical overload in the hypertrophied human adult myocardium

Intercellular dehiscence is a common cardiocytic response to pathological conditions. However, little consideration has been given to the possibility of new intercellular junctions developing between cardiocytes within developed myocardium. To examine this possibility as it may relate to useful compensation for hemodynamic overloads, changes in cardiocytic connection were evaluated by scanning electron microscopy in hypertrophied myocardium of adult human hearts. Transmural myocardium of left ventricle was obtained at autopsy from five hearts with concentric hypertrophy, five hearts with eccentric hypertrophy, and five control hearts (noncardiac death). After formalin fixation, the number of cardiocytes connected to an individual cardiocyte was counted in tissues from the middle portion of the transmural samples by scanning electron microscopy. Cardiocytic diameter and connective tissue volume fraction were measured on the transmural sections by light microscopy. In concentrically hypertrophied hearts present both increased cardiocytic diameter and connective tissue volume fraction, the number of other cardiocytes connected to an individual cardiocyte (4.60 +/- 0.10 [mean +/- SE] was significantly increased (P < .05) compared with control hearts (4.19 +/- 0.12) or eccentrically hypertrophied hearts (4.11 +/- 0.10). The increase in junctions per cardiocyte in concentrically hypertrophied hearts suggests that new connections had been generated. More junctions developing during hypertrophy could add another structural advantage to those of cardiocytic hypertrophy and connective tissue proliferation as compensatory adjustments to hemodynamic overload in concentrically hypertrophied hearts.

Immunological, genetic, and microbiological study of family members manifesting early-onset periodontitis

From the standpoint of host-parasite interactions, family studies help us understand the host defensive factors and the molecular mechanisms involved in the periodontal immune response. In this study, we report the immunological profile of host-defensive functions, human leukocyte antigen (HLA) phenotypes, and the microflora of a mother (rapidly progressive periodontitis), an older son (periodontally healthy), a younger son (localized juvenile periodontitis), and a daughter (localized juvenile periodontitis). We examined the peripheral neutrophil functions, phenotypic and functional analysis of peripheral lymphocytes, serum immunoglobulin G (IgG) antibody titers against periodontopathic bacteria, serological type of HLA class II antigens, and bacterial flora in all periodontal pockets. The results showed that Actinobacillus actinomycetemcomitans was dominant in the pockets of all subjects. The mother and two sons showed a depressed neutrophil chemotaxis to N-formyl-methionyl-leucyl-phenylalanine. All subjects except the older son exhibited low T4/T8 ratios. The mother and daughter had raised levels of IgG titers to Porphyromonas gingivalis. All subjects had HLA phenotypes of DRw52 and DQ1 in common. We found that the family members had similar disorders in certain defensive functions. This family has been a model for our understanding of the host defensive factors in the development of early-onset periodontitis.

Reconstitution of the F1-ATPase activity from purified alpha, beta, gamma and delta or epsilon subunits with glutathione S-transferase fused at their amino termini

Systems for overexpression and purification of active alpha, beta and gamma subunits of Escherichia coli H(+)-ATPase were established. The alpha and beta subunits recovered as soluble form were purified by hydroxyapatite column chromatography. Since the gamma subunit was overexpressed as the insoluble form, this subunit was purified by polyacrylamide gel-electrophoresis containing sodium dodecyl sulfate. By subsequent denaturation of this subunit with guanidine hydrochloride and renaturation, the active gamma subunit for reconstitution of the F1-ATPase activity with the purified alpha and beta subunit was obtained. The delta and epsilon subunits which were fused to the carboxy terminus of glutathione S-transferase (GST) were overproduced and purified by affinity chromatography. These fused proteins (delta-GST and epsilon-GST) were incubated with the purified alpha, beta and gamma subunits and applied to affinity chromatography. The alpha beta gamma delta-GST and alpha beta gamma epsilon-GST complex were eluted specifically by addition of glutathione and exhibited high and low ATPase activity, respectively, with a subunit stoichiometry similar to that in the native F1-ATPase, indicating that active complexes could be reconstituted with the fused proteins. These results suggested that the amino-terminal ends of the delta and epsilon subunits are not involved in formation of the active complex. The fused epsilon-GST bound the gamma subunit strongly, and the alpha subunit weakly. The delta-GST bound the gamma subunit significantly, and the alpha and beta subunits very weakly.

Preclinical Cushing's syndrome: report of four cases and analysis of steroid contents in adenomas

We report 4 cases of preclinical Cushing's syndrome (PCS) that were discovered incidentally by computed tomography (CT) as adrenal incidentalomas. Routine endocrine examinations revealed a suppressed plasma ACTH level. A final diagnosis was made by means of precise endocrine assessments and adrenal scintigraphy with radiolabelled iodocholesterol. Although endocrine data varied, the positive accumulation of radioisotope in the adrenal tumor, with nonvisualization of the contralateral side, was observed in all cases. Endocrine studies and analyses of steroid contents in tumors by HPLC suggested that subtypes or heterogeneous forms of this disease entity may exist. One type shows small tumors with relatively elevated cortisol production, and a disturbed diurnal rhythm and suppression of plasma cortisol with dexamethasone (DXM). The other type showed large tumors with weak-to-average cortisol production, and the diurnal rhythm of cortisol was preserved.

[A case of virus-associated hemophagocytic syndrome (VAHS) complicated by rhabdomyolysis which were associated with herpes-simplex virus infection]

A 60-year-old male was admitted to our hospital complaining abdominal pain and fatigue. Complete blood count showed as follows; WBC 3,900/microliters (48% of monocytes), Hb 11.5 g/dl, Plt 0.9 x 10(4)/microliters. Marrow smears showed the presence of phagocytic histiocytes that consist 22.4% of total nuclear cells. Laboratory findings showed as follows; BUN 109.5 mg/dl, Creatinine 7.4 mg/dl, CPK 1,259 IU/l, Aldolase 195 IU/l, Myoglobin 4,200 mg/dl. Serological studies showed a 16-fold increase in herpes-simplex virus (HSV) antibody titers 4 weeks after admission. So we diagnosed his illness as virus-associated hemophagocytic syndrome (VAHS) and rhabdomyolysis that were associated with HSV. We performed three times of hemodialysis for acute renal failure and used prednisolone for VAHS. These treatments were successful, and he made a complete recovery from illness. VAHS complicated by rhabdomyolysis is very rare, and we think this case is full of suggestions.

Regional differences in transient outward current density and inhomogeneities of repolarization in rabbit right atrium

BACKGROUND

Recent experimental and clinical studies on atrial flutter have demonstrated that the crista terminalis (CT) plays an important role in the genesis of atrial reentry. To elucidate the underlying mechanism of its role, we characterized the electrophysiological repolarization properties of CT cells by comparing them with those of the pectinate muscles (PM).

METHODS AND RESULTS

After action potential properties of both regions were compared by conventional microelectrode technique in multicellular atrial tissues, the whole-cell clamp experiments were applied in atrial cells isolated from both regions. Action potential duration (APD) was more prolonged in CT than in PM in multicellular preparations (APD90 77 +/- 5 ms versus 52 +/- 8 ms at 1 Hz, P < .01), though the other properties did not differ significantly. Similarly, in isolated atrial cells, APD was more prolonged in CT cells than in PM cells (APD90 63 +/- 7 ms versus 41 +/- 6 ms at 0.1 Hz, P < .01). Isolated single cells were larger in CT than in PM. The whole-cell clamp recordings showed no definite distinctions in the density of the voltage-dependent L-type Ca2+ current and the inwardly rectifying K+ current between these cells but revealed a significant reduction of the density of the 4-aminopyridine-sensitive transient outward current (Ito) in CT cells compared with that in PM cells (6.3 +/- 0.7 pA/pF versus 10.3 +/- 0.8 pA/pF at +20 mV, P < .05). However, no differences in the kinetics or the voltage dependence of Ito were observed between the cells. The time course of recovery from inactivation of Ito was also similar in both types of cells.

CONCLUSIONS

These results suggest that the preferential reduction in the density of Ito in the CT cells could contribute to prolong their APD, which may be related to the genesis of atrial reentry.

Leukocytapheresis therapy with leukocyte removal filter for inflammatory bowel disease

Leukocytapheresis (LCAP) with a leukocyte removal filter was administered to 44 patients with inflammatory bowel disease (IBD), diagnosed as ulcerative colitis (UC) in 25 and Crohn's disease (CD) in 19. Clinical and blood examinations showed no side effects in any of the patients. During intensive therapy, clinical improvement was recognized in 21 of the 25 UC patients (84%), 8 of whom had an excellent response, and in 16 of the 19 CD patients (84.2%), 4 of whom had an excellent response. The clinical improvement continued throughout the maintenance therapy in 19 of the UC patients (76%) and in 12 of the CD patients (63.2%). In both the UC and the CD patients, flow cytometry study showed that those who had improved generally had high values for the percentages of HLADR+, HLADR+CD3+, HLADR+CD8+, and CD11a+CD8+ cells before the first LCAP, and that these values decreased to near the normal range after both intensive and maintenance therapy. In the patients who showed poor response, in contrast, the values had been at or near normal before the initial LCAP administration. The clinical improvement and the findings on flow cytometry suggest that LCAP exerts an immuno-modulatory effect and is an effective therapy for patients with IBD in whom conventional drug treatments have failed.

Interferon-alpha-induced apoptosis in human erythroid progenitors

Recombinant human interferon-alpha (rIFN-alpha) inhibits erythropoiesis, in vivo and in vitro. In an attempt to clarify mechanisms related to this inhibition, effects of rIFN-alpha on highly purified human peripheral blood burst-forming units-erythroid (BFU-E) (20-60% purity) were compared with effects on erythroid progenitors in various stages of development. Day-1 and -7 cultured cells were equivalent to primitive BFU-E and colony-forming units-erythroid (CFU-E), respectively. Day-1 BFU-E supported by recombinant human erythropoietin (rEpo) and interleukin-3 (rIL-3) was inhibited by rIFN-alpha in a dose-dependent manner, and a significant inhibition occurred at 2000 U/mL rIFN-alpha. Limiting dilution analysis demonstrated that rIFN-alpha directly inhibits BFU-E rIFN-alpha inhibited the proliferative capacity or the colony expression of erythroid progenitors, with no relation to the stage of development, but inhibition of differentiation was not apparent. This evidence suggested that apoptosis of erythroid progenitors was induced by IFN-alpha. When day-7 cells were incubated with IFN-alpha in the presence of rEpo, there was an increased breakdown of total cellular DNA into DNA fragments of less than 5 kb; hence, the inhibitory effect of IFN-alpha on erythroid progenitors may mediate apoptosis.

Occurrence of Graves' disease during retreatment with interferon-alpha 2a for chronic hepatitis C

The present report describes a patient who developed Graves' disease 3 months after inception of retreatment with higher doses of interferon-alpha 2a for chronic hepatitis C, although the initial 6-month treatment caused no serious adverse reactions. Severe hyperthyroidism continued despite discontinuation of interferon-alpha 2a, and the patient was subsequently treated with 131I. This case suggests careful evaluation of the safety of retreatment to prevent manifestation of such a complication in the retreatment of chronic hepatitis C with interferon.

Ultrasonographic evaluation of the carpal tunnel syndrome in hemodialysis patients

The carpal tunnel syndrome (CTS) is the most frequent clinical symptom of dialysis-related amyloidosis. We examined CTS by ultrasound imaging and correlation between CTS and bone amyloidosis was sought. One hundred and forty-two wrists of 71 hemodialysis (HD) patients and 28 of 14 normal volunteers (group 1) were studied. Patients on HD were divided into 4 groups based on HD duration: Group 2, less than 5 years; group 3, 5-10 years; group 4, 10-15 years; and group 5, more than 15 years. The frequency of CTS increased gradually with HD duration: 0% in group 2, 35.3% in group 3, 36.4% in group 4 and 74.1% in group 5. The thickness of the palmar radiocarpal ligament (PRL), corresponding to the posterior wall of the carpal tunnel was significantly greater in groups 4 (p < 0.05), and 5 (p < 0.05) than in group 1 (2.25 +/- 1.30 and 3.11 +/- 1.02 in group 4 and 5 vs 1.15 +/- 0.34 mm in group 1); and the width of the carpal tunnel (CT) was significantly larger in group 5 than in group 1 (6.92 +/- 1.78 in group 5 vs 5.53 +/- 1.48 mm in group 1, p < 0.05). Wrists operated on for CTS had significantly increased PRL and CT compared to the control group and patients without CTS. Patients with CTS had wider PRL than the control and HD patients without CTS. Cystic radiolucent lesions (CRL) of carpal bones characteristic of bone amyloidosis were noted in 15 of 71 HD patients. The thickness of PRL and width of CT in HD patients with CRL exceeded those in patients without CRL. These data indicated that ultrasonographic findings of wrists were closely correlated with the degree of CTS and CRL. The usefulness of ultrasonographic evaluation of PRL thickness and CT width in the evaluation of dialysis-related amyloidosis should be evaluated.

Vasorelaxant effect of isocarbacyclin methyl ester incorporated into lipid microspheres on isolated canine arteries

TTC-909 is a preparation of isocarbacyclin methyl ester (CAS 88931-51-5, TEI-9090) incorporated into lipid microspheres. The characteristics of vasorelaxation induced by TTC-909 were investigated in isolated canine arteries. TTC-909 produced concentration-dependent relaxation of prostaglandin F2a(PGF2a)-induced and U-46619 (TXA2 receptor agonist)-induced contraction in basilar, coronary, renal, mesenteric, and femoral arteries. The vasorelaxant potency of TTC-909 was compared with the potencies of TEI-9090, TEI-7165 (CAS 88911-35-7, free acid of TEI-9090), prostaglandin I2 (PGI2), and prostaglandin E1 (PGE1) on PGF2a-induced contraction in basilar and femoral arteries. The relaxing potency of TTC-909 was similar to the values for TEI-9090, TEI-7165, and PGI2, and more potent than that of PGE1 in both of these arteries. An esterase inhibitor, diisopropyl fluorophosphate (DFP), reduced the vasorelaxant effect of TEI-9090, but not that of TEI-7165, on PGF2a-induced contraction in femoral arteries. These results suggest that TTC-909 has vasorelaxant potency similar to that of PGI2 and greater than that of PGE1. Further, it appears that TEI-9090 was converted to TEI-7165 by esterase and then produced its vasorelaxing effect.

Effect of isocarbacyclin methyl ester incorporated in lipid microspheres on experimental models of peripheral obstructive disease

The effect of TTC-909 (isocarbacyclin methyl ester (CAS 88931-51-5, TEI-9090) incorporated into lipid microspheres) on obstruction of the peripheral artery was studied in two different animal models. The first was a peripheral occlusion model induced by intra-arterial injection of sodium laurate in rats. The second was a tail gangrene model induced by subcutaneous injection of both ergotamine and epinephrine in rats. Intravenous bolus-administered TTC-909 at 1.0 microgram/kg resulted in the inhibition of both progression of lesions induced by sodium laurate and the extension of tail gangrene by ergotamine and epinephrine. Moreover, the inhibitory effect of TTC-909 was more potent than that of PGE1 (LM) (prostaglandin E1 incorporated into lipid microspheres). These findings suggested that TTC-909 may be clinically useful for the therapy of peripheral vascular disorders such as thromboangiitis obliterans (TAO) and atherosclerosis obliterans (ASO).

Effect of isocarbacyclin methyl ester incorporated into lipid microspheres on cutaneous blood flow in rat

A new stable prostacyclin analogue, isocarbacyclin methyl ester (CAS 88931-51-5, TEI-9090), incorporated into lipid microspheres (TTC-909), was examined for its effects on cutaneous blood flow and mean blood pressure in rats in comparison with PGE1 (LM) (prostaglandin E1 in lipid microspheres). TTC-909 at 0.3 micrograms/kg i.v. significantly increased the sole cutaneous blood flow without changing blood pressure. A significant decrease in mean blood pressure was observed with TTC-909 above 1 microgram/kg i.v. PGE1 (LM) also showed a decrease in the blood pressure from 1 microgram/kg i.v., whereas the sole cutaneous blood flow was not affected even at 10 micrograms/kg i.v. These results suggest that TTC-909 dilates the skin vessels preferentially to other blood vessels in the rat and that effect is more potent than that of PGE1 (LM). TTC-909 may thus prove to be an effective agent for the treatment of peripheral vascular disease.

Inhibition of GM-CSF production by recombinant human interleukin-4: negative regulator of hematopoiesis

Interleukin-4 (IL-4), also known as B-cell stimulatory factor-1 (BSF-1), was initially identified as a T-cell product that mediates anti-IgM-induced DNA synthesis in B-lymphocytes. Various aspects of this highly pleiotropic cytokine have been described, including those on hematopoietic progenitor cells. However, the role of IL-4 in the hematopoietic system has been given different interpretations. Normal human hematopoietic progenitor cells do not proliferate under control of the autocrine system and cytokines are needed for proliferation and differentiation. However, IL-4 in itself does not support proliferation of these cells and if this is the case, the effects of IL-4 on hematopoietic progenitor cells still need to be investigated from the point of view of synergism with other cytokines as well as the control of accessory cells in the production of cytokines. We describe here some properties of IL-4 in association with cytokine production, with special emphasis on granulocyte-macrophage colony-stimulating factor (GM-CSF) production.

Two types of calcium channels sensitive to omega-agatoxin- TK in cultured rat hippocampal neurones

We characterized the electrophysiological properties of calcium channels in cultured rat hippocampal neurones using omega-agatoxin-TK (omega-Aga-TK) and compared them with those of the P-type channel and the BI (alpha 1A) channel which resembles the Q-type channel. Two types of omega-Aga-TK-sensitive calcium channels were detected in hippocampal neurones. The first type showed slow inactivation, high sensitivity to omega-Aga-TK and low reversibility from omega-Aga-TK-induced block, resembling the P-type channel. The second type showed fast inactivation, low sensitivity to omega-Aga-TK and high reversibility from omega-Aga-TK-induced block. These results suggest that the second type of calcium channel (Q-type-like) plays a prominent role in the hippocampal synaptic transmission.

Spatial ventricular gradient in patients with Wolff-Parkinson-White syndrome in comparison with normal subjects: vectorcardiographic evidence for significant repolarization changes due to preexcitation

We investigated the use of the spatial ventricular gradient (VG) from vectorcardiogram (VCG) to determine whether significant repolarization differences were present in patients with WPW syndrome compared with normal subjects and also examined which VG parameter (i.e., elevation, azimuth, and magnitude) reflected the differences in repolarization properties during preexcitation. VG was calculated in 49 patients of Wolff-Parkinson-White (WPW) syndrome (group A: left-sided accessory pathway, n = 29; group B: right-sided, n = 20). Group N consisted of 607 normal subjects. In group A, the azimuth of VG was significantly (p < 0.01) greater than in groups B and N. In group B, the elevation of VG was significantly (p < 0.01) greater than in groups A and N. There were no significant differences in the magnitude of VG among groups. QRS duration was significantly (p < 0.01) related with the elevation of VG in group B. These findings suggested that VG is useful for spatial evaluation of repolarization abnormalities during preexcitation, which are related to the site of the accessory pathway.

The predicted structure of chick lens CP49 and a variant thereof, CP49ins, the first vertebrate cytoplasmic intermediate filament protein with a lamin-like insertion in helix 1B

The full length cDNA sequence for the lens-specific intermediate filament protein, CP49, from chicken is presented. The sequence contains features typical of the other intermediate filament proteins, including two major alpha-helical regions, helix I and II and appropriate linker regions. CP49 lacks a C-terminal non-alpha-helical domain and is only the second intermediate filament protein to be described missing this feature. Comparison to the bovine CP49 shows significant homology in all domains except the N-terminal non-alpha-helical domain. Besides bovine CP49, the other protein most homologous to chicken CP49 in the database was keratin 18, a type I keratin. A variant of CP49 is also described, called CP49ins. Of the 61 positive clones identified in the library, two encoded CP49ins, one of these being a full-length clone. The sequence differed to CP49 by the insertion of 49 amino acids in helix IB. This is the first chordate cytoplasmic intermediate filament protein sequence to be identified with an archetypal lamin-like insertion in this helical subdomain and represents a key discovery in tracing the evolutionary pathway of intermediate filament protein family.

Leukocytapheresis therapy, performed with leukocyte removal filter, for inflammatory bowel disease

Leukocytapheresis (LCAP), performed with a leukocyte removal filter, was administered five times, at 1-week intervals, for 5 weeks of intensive therapy and five times, at approximately 1-month intervals, for approximately 5 months of maintenance therapy, to 13 patients with inflammatory bowel disease (IBD) diagnosed as ulcerative colitis (UC) in 8 and Crohn's disease (CD) in 5. Clinical and blood examinations showed no side effects in any of the patients. During the intensive therapy, excellent or moderate clinical response was recognized in 11 of the 13 patients (84.6%), of whom 6 had a dramatic response; the excellent or moderate clinical response continued throughout the maintenance therapy in 8 of the patients (61.5%). Flow cytometry showed that the patients who had improved generally had high values for percentages of HLADR+, HLADR+CD3+, and HLADR+CD8+ cells before the first LCAP, and that these values and the C-reactive protein levels and erythrocyte sedimentation rates had decreased to the normal range by the end of both intensive and maintenance therapy. In the patients who showed poor response, in contrast, all the above values had been at or near normal before the initial LCAP administration. The clinical improvement in the absence of any additional medical treatment suggests that LCAP has the capacity to influence the causal mechanism(s) of IBD and that IBD is strongly associated with the cell-mediated immune response.

Adhesive substrates influence acid-productive activities of cultured rabbit osteoclasts: cultured osteoclasts with large vacuoles have enhanced acid-productive activities

Since acid secretion of polarized osteoclasts on the bone surface has an important role in bone resorption, we examined the acid-productive activities of osteoclasts by measuring the pH of acidic organelles such as endosomes, lysosomes, and vacuoles in cultured rabbit osteoclasts with FITC-dextran as a fluorescent pH probe. The average pH value of acidic organelles of osteoclasts cultured on plain glass coverslips was 5.3 +/- 0.2. The pH of the acidic organelles correlated well with the size and amount of the vacuoles in the cells. Using this FITC-dextran method, we also examined the effects of adhesive substrates, such as type I collagen, vitronectin, and dentine, on the acid-productive activities of osteoclasts and found that the pH value of acidic organelles of osteoclasts cultured on dentine slices was significantly lower than that of osteoclasts cultured on plain glass coverslips. Likewise, in the case of the osteoclasts cultured on type I collagen- or vitronectin-coated glass coverslips, the pH values of acidic organelles were slightly lower and the proportion of osteoclasts having large vacuoles was increased compared with the cells cultured on the plain glass coverslips. These results indicate that osteoclasts containing large vacuoles have high acid-productive activities, and adhesive substrates such as type I collagen and vitronectin influence the formation of large vacuoles in cultured osteoclasts.

Developmental pattern of androgen receptor immunoreactivity in the mouse submandibular gland

We studied the immunohistochemical localization of androgen receptor in the mouse submandibular gland, and developmental profiles of its expression using polyclonal human androgen receptor antibody. In the submandibular glands of both sexes, specific immunoreactivity appeared only in cell nuclei of the acini, the intercalated ducts, the granular convoluted tubules (GCT) and the excretory striated ducts. The percentage of immunoreactive cells in each region gradually declined with age during the first 90 days of postnatal development studied. The sexual difference in the percentage of immunoreactive cells was observed in the acini on days 20 and 30 and in the GCT on day 30. Incidence of immunoreactive cells in the female was significantly smaller than that in the male. On day 60, the percentage of immunoreactive cells of these two regions turned to increase slightly in the female but continued to decline in the male, and then it became higher in the female than in the male. In addition, one-week castration did not cause any changes in the intracellular distribution of androgen receptor and the percentage of immunoreactive cells in each region of the adult gland. These results suggest that androgen receptor is localized primarily in cell nuclei in all four regions of the mouse submandibular gland in situ, and that its expression in acini and GCT is superior in the male around days 20 to 30, when sex difference of the gland becomes evident.

FK143, a novel nonsteroidal inhibitor of steroid 5 alpha-reductase: (2) In vivo effects on rat and dog prostates

FK143 is a nonsteroidal new inhibitor of steroid 5 alpha-reductase, an enzyme which converts testosterone into 5 alpha-dihydrotestosterone (DHT). We studied in vivo effects of FK143 on rat and dog prostates. FK143 was orally administered to mature male rats for 14 days. At doses above 1 mg/kg, FK143 significantly reduced the wet weights of the ventral prostate and seminal vesicle, but showed no effects on those of the epididymis, testis, and adrenal. Growth of ventral prostate and seminal vesicle was induced by the subcutaneous injection of testosterone propionate (TP) in the castrated young rats and was reduced by FK143 administration at doses above 3.2 mg/kg, while growth induced by 5 alpha-dihydrotestosterone propionate (DHTP) was not affected. FK143 had no binding affinity for the rat androgen receptor. FK143 showed neither estrogenic and antiestrogenic effects on the rat uterus nor androgenic effect on the rat prostate. Concentration of testosterone and DHT in the rat and dog prostates were measured by GC-MS, and administration of 10 mg/kg of FK143 significantly reduced the intraprostatic concentration of DHT. These results indicate that FK143 reduced the prostate growth by inhibiting 5 alpha-reductase activities in the prostates.

FK143, a novel nonsteroidal inhibitor of steroid 5 alpha-reductase: (1) In vitro effects on human and animal prostatic enzymes

Steroid 5 alpha-reductase is an enzyme which converts testosterone into 5 alpha-dihydrotestosterone (DHT) and is implicated in the pathogenesis of benign prostatic hyperplasia (BPH) in men. We studied in vitro effects of FK143, a nonsteroidal new compound, on 5 alpha-reductase in human and animal prostates. Prostates were obtained from Wistar rats, Beagle dogs, and Cynomolgus monkeys as well as prostatic tissue from BPH patients obtained by the prostatectomy. Nuclear membrane fraction of prostates showed pH dependent 5 alpha-reductase activities, and inhibitory effects of drugs were assayed at pH 6.5. FK143 inhibited human prostatic 5 alpha-reductase in a dose-dependent manner with an IC50 of 1.9 nM and also inhibited animal 5 alpha-reductases with similar IC50 values. FK143 inhibited human and rat 5 alpha-reductases in a noncompetitive fashion while finasteride, a steroidal 5 alpha-reductase inhibitor, showed competitive inhibition. The affinities of FK143 for the human 5 alpha-reductase is constant at pH 5 and 6.5. No inhibitory effects were shown to other oxidoreductases. These results indicate that FK143 is a new type of potent and selective 5 alpha-reductase inhibitor.

Proliferation and differentiation of myelodysplastic CD34+ cells in serum-free medium: II. Response to combined colony-stimulating factors

To investigate the role of colony stimulating factors (CSFs) in the proliferation and differentiation of progenitor cells from myelodysplastic syndromes (MDS), marrow progenitor cells from 18 MDS patients were highly purified using CD34 monoclonal antibody and immunomagnetic microspheres (MDS CD34+ cells). These cells were cultured in serum-free medium with various combinations of five colony stimulating factors (CSFs): recombinant human interleukin-3 (rIL-3), granulocyte/macrophage-CSF (rGM-CSF), granulocyte-CSF (rG-CSF), macrophage-CSF (rM-CSF), and erythropoietin (rEP). Among the tested CSFs, such as rM-CSF, rG-CSF, rGM-CSF and rIL-3, a combination of the first three CSFs was the most effective stimulus for the proliferation of non-erythroid MDS progenitor cells. An increase of undifferentiated "blast" cell colonies in 5/18 MDS patients occurred and these 5 patients belonged to the high-risk group. In the presence of these three CSFs, rIL-3 had no effect on the proliferation and differentiation of MDS CD34+ cells; however, IL-3 was efficient for the proliferation of MDS CD34+ cells to the erythroid lineage. rGM-CSF or rIL-3 alone did not efficiently support proliferation and differentiation of CD34+ cells. M-CSF is present in normal human serum at a concentration of 550 +/- 110 U/ml, a concentration exceeding that used in this study (100 U/ml). Therefore, in vivo administration of G-CSF combined with GM-CSF to MDS patients may be one of the most effective CSF combinations for proliferation of MDS progenitor cells to the non-erythroid lineage. However, the effect on the capacity for differentiation was minimal, especially in patients belonging to the high-risk group.