A short-term incubation of isolated rat fat pads with vanadate showed the stimulated release of lipoprotein lipase (LPL) activity and suppression of the rise in extracellular adenosine level. The addition of adenosine to the medium showed inhibition of both the stimulated release of LPL activity and an increase in intracellular cAMP content by vanadate. A progressive increase in 5'-nucleotidase activity in the particulate fraction containing plasma membrane was supressed by vanadate in a time- and dose-dependent manner, suggesting that vanadate inhibits, in part, the production of adenosine based on a dephosphorylation of AMP. In adipocytes, the inhibition of adenylate cyclase via A₁ adenosine receptor is more predominant than the stimulation of adenylate cyclase via A₂ adenosine receptor (Londos C. et al., Proc. Natl. Acad. Sci. U.S.A., 75, 5362-5366 (1978)).Therefore, vanadate may stimulate the release of LPL activity from the fat pads by suppressing the rise in extracellular adenosine level, accompanied by the activation of adenylate cyclase activity.

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Two types of recombinant plasmids containing 600 bp Nde I fragments that coded the bsr gene in opposite directions were obtaind. Nucleotide sequencing shows that the bsr encodes a 140 amino acid protein with a putative molecular weight of 15560, the same as that of purified blasticidin S (BS)-deaminase (BSR), on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) (15500). Upstream of the open reading frame, a Shine-Dalgarno (SD) sequence, frequent inverted repeats, and the σ^A and σ^B promoter sequences are observed. The tarnscriptional start point was determined to be the A located 7 bases downstream from the putative σ^A promoter (⁹¹TTGATC and ¹¹³TAAAAT) by the primer estension method and site directed mutagenesis at the -10 or -35 promoter region.A comparison of the amino acid sequence of BSR with that of BS-deaminase from Aspergillus terreus (BSD) showed 27.2% homology. Low degrees of homology were also observed with cytidine deaminase and deoxy cytidine monophosphate (CMP) deaminase. Four conserved amino acid motifs were observed, VGAx₆ G, C(orH)AEx₆A, SPCGxCR, and Gx₈ELIP (x_n indicates a nonspecific residue and its position). It is possible that the three Cys residues and the Glu in the conserved motifs comprise the active center. Site-directed mutagenesis of the Cys residues supports this possibility.

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An assay system was constructured to identify chemicals that have a potential to induce p21/WAF1 gene, a target of the tumor suppressor p53 critical for negative growth regulation. Screeening of about 1300 culture fluids of Streptomyces resulted in identification of active substances which induced the p21 gene in a p53-independent manner; one was a mixture of four members of the actinomycin group, and the other was trichostatin A. Tarnscriptonal regulatory regions of p21 gene for induction by actinomycin D and trichostatin A were determined by transient expression of luciferase constructs in cells which are p53-deficient (Saos-2) or express a mutated form of p53 (TMK-1). The essential tarnscriptional elements for the response to these drugs localize within 210 bp of the 5'-upstream region of human p21 gene, and Sp1 elements were determined to be critical for the induction. DNA-binding activity of Sp1 was not increased in cells treated with these drugs, but kinase inhibitors such as staurosporin and wortmannin inhibited the induction.

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Although the induction of heat shock proteins (HSP) has been studied extensively in cultured cells, compariatively few studies have examined their expression in vivo. In this report, we investigated the expression and the state of 105-kDa heat shock protein (HSP105) in various tissues of rats, and found that two isoforms of HSP105 (HSP105-a and HSP105-b) were both moderately expressed in adrenal, spleen, liver and heart, and both increased markedly after heat shock. However, in brain HSP105-a was characteristically highly expressed over HSP105-b, but neither increased after heat shock. In addition, a 100-kDa protein (p100), a possible testis-specific HSP105 homologue was found in testis. When the effects of adrenaline and its antagonists on the heat-inducibility of HSP105 were examined, the induction of HSP105 in adrenal gland seemed to be negatively regulated through the α-adrenergic receptor. Furthermore, HSP105 was found to be associated with HSC70/HSP70, and to exist as high molecular mass complexes of 300-800-kDa and of 300-500-kDa in various tissues of nonstressed and heat-stressed rats, respectively. The molecular interaction between HSP105 and HSC70 suggests the possibility that HSP105 functions with HSC70 cooperatively in various tissues of rats.

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The telomere is a specialized chromatin structure composed of unique repetitive DNA sequences and specific nuclear proteins. Telomere sequence-binding activity was measured by a mobility shift assay using nuclear extract from normal human fibroblasts. The specific binding activity to the telomere sequence increased in cells that were in a senscence state compared to that in cells at early population doublings. Treatment of cells with tumor promoting phorbol ester TPA induced an increase in the telomere sequence binding activity of nuclear extract in young cells, but the increase was marginal in senescent cells. DNA-damaging N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) also increased the telomere sequence binding activity in young cells, but not in senescent cells. As a reference, we measured the binding activity to NFkB sequence. It was activated by TPA or okadaic acid, but was not affected by MNNG or in senescence. The increase in telomere sequence-binding activity seemed to depend on activation of tyrosine phosphorylation, since an inhibitor of Tyr-kinase abolished the increase in telomere-binding activity. The molecular weight of the major binding factor in the normal human fibroblasts was approximately 32 kDa which is different from that of the telomere-associated protein, TRF-1.

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Shichimotsu-koka-to (SKT) has been prescribed to treat patients with essential and renal hypertension. We investigated the effects of SKT on renal lesions in stroke-prone spontaneously hypertensive rats (SHRSPs). SHRSPs were gievn an extarct of SKT by mixing it with drinking water, from 8 through 29 weeks of age, so that the average intake of SKT extract was about 1.5 g/kg/d. At 29 weekd of age, the kidneys of SHRSPs exhibited proliferative arteritis characterized by the proliferation of smooth muscle cells in the interloubular arteries, dilation and degeneration of renal tubules, infiltration of inflammatory cells and hemorrhage, with partial swelling or necrotizing of glomeruli. In particular, arteritis and periarteritis were noted. The treatment of SHRSPs with SKT ameliorated this morphological damage in the kidney and significantly decreased urea nitrogen in the serum. Treatment with SKT also strongly decreased the xanthine oxidase (XOD) activity and significantly increased the superoxide dismutase (SOD) activity in the kidney of SHRSPs; consequently, these values became close to those in normotensive Wistar Kyoto rats (WKYs). These results indicate that treatment with SKT ameliorated the histopathological damage and change in activity of enzymes related to free radicals in the kidney of SHRSPs, which may be important mechanisms for SKT for protecting SHRSPs from renal dysfunction.

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Fluoroquinolone antibiotics and chemically related compounds in cluding the pazufloxacin methanesulfonate named T-3762 were examined for their ability to increase cutaneous vascular permeability following intradermal injection in dogs. A positive skin reaction was produced by the injection of a compound with a substituent of the piperazinyl, 4-piperizyl, 3-aminopyrolizinyl or 3-aminocyclobutyl group at the 7-position (C-7) of the quinolone skeleton at a minimum concentration of 101.8 μg/ml or less. Substitution at position 1, 6 or 8 of the ring nucleus hardly affected the activity of the compounds with the C-7 substituted piperazinyl group. The compounds with 7-positioned substituents other than the piperazinyl group showed relatively weak activity, and in particular those with the 1-aminocyclopropyl group including T-3762 were barely positive in concentrations of more than 500 μg/ml. An analysis of the three-dimensional models of the compounds with the C-7 substituted, nitrogen-containing groups revealed that the range of the geometrically optimum distance between the nitrogen and the carbon atoms was from 2.98 to 4.98 Å for highly active compounds and from 2.47 to 2.65 Å for weakly active compounds. In conclusion, the C-7 substituted piperazine moiety of the molecules of already-known fluoroquinolone antibiotics may be responsible for the ability to increase cutaneous vascular permeability, whereas T-3762 is practically inactive because the free amino nitrogen of the 1-aminocyclopropyl group is conformationally present at a shorter distance from the carbon atom at position 7 of the ring nucleus.

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By means of successive heparin-affinity and glycyrrhizin (GL)-affinity column chromatographies (HPLC), a 55 kDa GL-binding protein (gp55) was purified to apparent homogeneity from the Superdex P-I fraction of Habu snake venom. This gp55 was identified as an apoxin I-like protein, because (i) its 20 N-terminal amino acid residues (AHDRNPLEEYFRETDYEEFL) are 95% identical with the corresponding sequence of apoxin I (apoptosis-inducing factor, approx. 55 kDa) in the venom of the western diamondback rattlesnake; and (ii) L-amino acid oxidase (LAO) activity of gp55 is detected when incubated with L-leucine, but not with D-leucine. GL inhibited the LAO activity of gp55 in a dose-dependent manner, but had no effect on the activity of a 65 kDa LAO also purified from Habu snake venom. In addition, GL reduced the ability of gp55 to induce the hemolysis of sheep red blood cells. These results suggest that GL is a potent inhibitor of apoxin I-like proteins in harmful snake venoms.

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The hypoglycemic effect of the novel oral agent 3-{4-[2-(5-methyl-2-phenyl-oxazol-4-yl)-ethoxyl]-phenyl}-2S-propylamino-propionic acid (HQL-975) was examined in db/db mice with genetically obese non-insulin dependent diabetes mellitus (NIDDM). The oral administration of HQL-975 at 3.5 and 35.3 mg/kg/d for 7 d decreased the plasma glucose level of these mice in a dose-dependent manner. HQL-975 also significantly decreased the plasma triglyceride, total cholesterol, non-esterified fatty acid and insulin levels. In the oral glucose tolerance test, HQL-975-treated mice showed improved glucose tolerance and decreased endogenous insulin secretion. HQL-975 increased glycemic response to exogenous insulin in the mice. In the HQL-975-treated db/db mice adipocytes, the glucose uptake, insulin binding, and GLUT4 expression were increased compared with those in untreated db/db mice adipocytes. These results indicate that HQL-975 improved insulin action in db/db mice through receptor and post-receptor effects.In conclusion, HQL-975 is a new oral antidiabetic agent with a hypoglycemic effect which is associated with an insulin-sensitizing effect. This agent may therefor be effective for the treatment of NIDDM.

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Whether a single dose of doxapram (DOP) can modulate the acteu toxicity and the hepatotoxicity induced by acetaminphen (AA) was examined. Pretreatment with DOP (40 mg/kg, i.p.) 30 min prior to the administration of AA dose-dependently potentiated the lethality of AA in both native mice and mice fasted for 18 h, and the potentiating activity was greater in fasted mice than in native mice. The hepatotoxicity of AA was assessed by plasma transaminases activity (glutamyl oxaloacetic transaminase, GOT; glutamyl pyruvic transaminase. GPT) and the amount of plasma lipid peroxides at 6, 12, 18, 24, 36 and 48 h after the administration of AA and histopathological examination of liver sections at 24 h after the administration of AA. DOP (40 mg/kg, i.p.) did not increase the plasma transaminase activity or the lipid peroxides level significantly, whereas AA administration to DOP-treated animals produced eariler maximal elevation of transaminase and lipid peroxide values compared to AA alone. These findings indicate that mortality and hepatotoxicity of AA is potentiated by DOP in mice.

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We studied inflammatory reactions induced by dermal application of the β-blocker propranolol (PRL) in ethanol to guinea pigs in orer to elucidate the relation of the reactions with the cumulative PRL permeating amount throgh the stratum corneum or the PRL content in the stripped skin, and to investigate the chemical mediators responsible for the reactions. The cumulative PRL permeating amount through the stratum corneum increased rapidly up to 2 h after dermal application, then increased linearly with time up to 24 h after application. Visual observation revealed formation of erythema and edema at the applied site of PRL, and histopathological examination revealed infiltration of pseudoeosinophiles of dermis and epidermis and degeneration/necrosis of epidermis. In general, it was considered that the duration and the extent of these reactions were dependent on the PRL dosage and application time. It was expected that the cumulative PRL permeating amount through the stratum corneum could be used to predict possible inflammatory reactions during development of transdermal drug delivery systems. On the other hand, contact of PRL with guinea pig skin tissues released histamine, and intradermal injeciton of PRL caused an increase of capillary permeability at the site of application. Also, the inhibitory effects of anti-inflammatory agents (diphenydramine, dexamethasone, indomethacin, cyproheptadine hydrochloride, CV3988 and AA-861) to RRL-induced erythema formation demonstrated that histamine and prostaglandins were responsible for the inflammatory reactions induced by PRL.

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Asterriquinone (ARQ) is an antitumor metabolite of Aspergillus terreus IFO 6123. In this study we synthesized several ARQ alkyl ethers and studied theircytotoxic activity against mouse leukemia P388 cells. The dissociation constant was also similar among the ARQ monoalkyl ethers. There was a good correlation between the hydrophobicity of ARQ monoalkyl ethers estimated by high performance liquid chromatography and the intracellular content accumulated for 60 min. ARQ monoalkyl ethers were cytotoxic, but ARQ dimethyl ether was not, as previously reported. The cytotoxicity of the ARQ monoalkyl ether derivatives was increased with extension of the alkyl chain lenght. The cytotoxity was closely correlated with the intracellular content. The strongest ARQ derivative, ARQ monohexyl ether (ARQHex), formed more DNA-interstrand cross-links in the cells than ARQ. After treatment of P388 cells with ARQ and ARQHex for 6 h, a nucleosomal ladder pattern, as well as the appearance of degraded DNA, observed by flow cytometry, indicated tha these compounds caused cellular apoptosis. Moreover, ARQ and ARQHex accumulated in the cells at the G₁ phase of the cell cycle. These results indicated that ARQ monoalkyl ethers increased cytotoxicity, according to their membrane permeability based on the hydrophobicity, and they caused apoptotic cell death, as did ARQ.

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The effect of shikonin (SK) on granulation tissue formation was biochemically evaluated and the biological effect of SK on cotton pellet induced granulation tissue formation and the induction of hind paw edema was compared with that of λ-carrageenan (carrageenan) in rats. The dry weight of granulation tissue formed was increased by SK. The amounts of hemoglobin and hydroxyproline in granulation tissue were also increased by SK. These results suggest that SK has an enhancing effect on the formation of granulation tissue, accompanied by the proliferation of capillaries and the increased production of collagen in rats. SK showed mild stimulation toward swelling when injected into the hind paws of rats, as did carrageenan, while it showed a marked enhancing effect on granulation tissue formation compared with carrageenan. These results suggest that the mechanism underlying the biological effect of SK on granulation tissue formation is different from that of carrageenan, though the mild stimulation by SK might still contribute in part to the enhancing effect on granulation tissue formation.

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In a study on teh metabolism of flavonoids, the isoflavone glycoside daidzin was orally administered to rats. Urine samples were collected and treated with β-glucuronidase and arylsulfatase. Aglycone daidzein (M3) and other three metaboliters, 3', 4', 7-trihydroxyisoflavone (M1), 4', 7-dihydroxyisoflavanone (M2) and 4', 7-dihydroxyisoflavan (M4) were isolatd from the urine following treatment with enzymes. The structures of M1, M2 and M4 were determined on the basis of chemical and spectral data.

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2-Methylimidazole (2MI), as well as imidazole, has been though to undergo cupro-ascorbate (Cu-VC)-catalyzed oxidative transformation in vitro to become a reactive species capable of combining with aldehydes intrinsic to connective-tissue proteins. We attempted to seize the essence of the above reaction through obtaining the structural information of an aldehyde-bonding species. As major products from 2MI in the in vitro Cu-VC system, 2-hydroxymethylimidazole (2(OH)MI) and 2-methyl-4-(5H)(or 5(4H))-imidazolone (2MIone) were identified by mass-spectral and chromatographic comparison with the corresponding authentic standards synthesized. The in situ addition of acetaldehyde or propionaldehyde as a simple protein-aldehyde model to the system resulted in the deducible formation of an aldol condensate, 2-methyl-4(or 5)-ethylidene-4(5H)(or 5(4H))-imidazolone (2MEIone) or its possible analogue with a propylidene moiety, respectively. The authentic compound of 2MIone directly reacted with acetaldehyde and easily afforded the products assignable to the isomers of 2MEIone through the ethylidfene moiety at physiological pH and temperature, whereas neither 2MI or 2(OH)MI reacted at all. These results suggest that a 4(5H)(or 5(4H))-imidazolone product, although simply a monooxygenated form, is sufficiently reactive to give aldol condensation-typed covalent adducts with aldehydes, even under physiological conditions, probably having an activated methylene moiety in the ring strucuture. Based on the present results, we discussed the mechanism of the retention of imidazole-containing drugs in connective tissue.

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The size of liposomes is considered to be an important factor in determining the liposome-complement interaction. In this study, the erlease of carboxyfluorescein (CF) from liposomes was measured continuously for three different diameters (800, 400 and 200 nm) by changing the liposome concentration from 1 to 1000 nmol/ml. At a low liposome concentration range (1-10 nmol/ml), small liposomes (200 nm) released CF to a similar extent (approximately 35%) as in the medium (400 nm) and large (800 nm) liposomes. The affinity (K_m) and capacity (L_max) of a complement system to release liposomally encapsulated CF were estimated by kinetic analysis of the liposome-complement interaction. Surprisingly, there was no remarkable size dependency in the K_m and L_max in terms of liposome number, although these parameters depended on the size of liposomes in terms of lipid concentration. These results indicated the possibility that the complement system does not discriminate according to liposome size.

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The uptake mechanisms of liposomes by rat peritoneal macrophages (PMs) were investigated. Incubation of liposomes with fresh rat serum enhanced the uptake of liposomes depending on the liposome size and cholesterol (CH) content. The binding of liposomes was also enhanced by serum, and this increase depended on the size and CH content as in the case of liposome uptake, which suggested that the binding of opsonized liposomes with PMs govern the extent in liposome uptake. The rate constant for the internalization (k_int) was calculated by measuring both uptake and binding. The k_int cannot explain the variation of liposome uptake for different sizes and CH contents. The kint values for liposomes with high (44%) and medium (33%) CH contents were constant (2.5^-1), while those for liposomes with low (22%) Ch content were significantly elevated (5-9h^-1). These results indicate the persence of at least two kinds of uptake mechanisms of liposomes. Treatment of serum with anti-C3 antiobdy completly inhibited the enhanced uptake of CH-high, large liposomes, which suggested that complement receptor-mediated phagocytosis may be an uptake mechanism for CH-high and -medium liposomes. In addition, complement-independent enhanced uptake was suggested for CH-low liposomes, since no inhibition was observed for CH-low liposomes by anti-C3 antibody and these liposomes were disintegrated in serum via complement-independent pathway. These results provided evidence that PMs take up liposomes via complement-dependent and indepenedent mechanisms depending on the CH content of the liposomes.

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The effect of grifolan (GRN), a gel-forming (1→6)-branched (1→3)-β-D-glucan, on antibody produciton were examined. Sera from mice that were injected with GRN and trinitrophenyl ovalbumin (TNP-OVA) intraperitoneally showed a significantly increased level of anti-TNP IgG. However, injection of CRN and 10 μg of TNP-OVA alone showed a lowe antibody level. Two hundred fifty μg of TNP-OVA gave the maximum production of anti-TNP antibody. Enhanced antibody prduction was also observed in the culture supernatant of splenocyte obtained from GRN-administered mice. The culture supernatant contained a significant amount of nitric oxide (NO) in the case of GRN-administered mice. To observe the effect of NO on the antibody production induced by GRN, N-menomethyl arginine (NMMA), an inhibitor of NO synthetase, was added to the splenocyte cultures. The antibody level of supernatants containing NMMA was higher than that of control supernatants. These results suggest that GRN can enhance antibody production and that NO induced by stimulation with GRN concomitantlywith antibody production is a negative factor on the adjuvant activity. Inhibition of NO may increase the adjuvant effect of GRN.

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To elucidate the antioxidant action of Vietnamese ginseng saponin against free radial-mediated cellular damage, we examined the effect of Vietnamese ginseng saponin on lipid peroxidation in the mouse brain, liver, and liver microsomes by using two in vitro free radical generating systems (iron ferrous+ascorbic acid and iron ferrous+hydrogen peroxide). Free radical-mediated lipid peroxidation was determined by measuring the endogenous and stimulated accumulation of thiobarbituric acid reactive substance (TBA-RS). Vietnamese ginseng saponin (0.05-0.5 mg/ml), as well as vitamin E, significantly inhibited the formation of TBA-RS in tissue homogenates. Panax ginseng saponin, at the same concentration range as Vietnamese ginseng saponin, also had inhibitory action on free radical-mediated lipid peroxidation. However, majonoside-R2, ginsenoside Rg₁ and ginsenoside-Rb₁, the main saponin components of Vietnamese ginseng saponin fraction, had no effect on lipid peroxidation. These results suggest that Vietnamese ginseng exerts a protective action against free radical-induced tissue injury and that this effect is attributable to minor components rather than the main saponin components tested.

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This paper reports the active glycosidases in normal human lenses and their partial properties. In addition, variations in their enzyme activities during aging and with the advance of lens coloration were also examined. Five glycosidases, α-D-glucosidase, β-D-glucuronidase, N-acetyl-β-D-glucosaminidase, β-D-cellobiosidase, and α-L-fucosidase, were detercted as active glycosidases in the normal human lens. However, the activity of β-D-cellobiosidase was considerably low as compard to the other four glycosidases. Thus, this enzyme was omitted from this study. The four glycosidases, α-D-glucosidase, β-D-glucuronidase, N-acetyl-β-D-glucosaminidase, and α-L-fucosidase, showed that their enzyme activities fell abruptly between the ages of 40 and 50. Furthermore, the K_m values of their enzymes exhibited some variability during aging. Namely, the K_m values of their enzymes indicated the lowest value between the 40 age group and 50 age group, suggesting that the substrate affinity became the strongest at these age groups.Then, variations in enzyme activity with the advance of lens coloration were examined. In each cases, the specific activity of detectable glycosidases in color lenses, white to brown, decreased. In particular, the specific activity of enzymes in the brown lens was very low, indicating that glycosidases in the brown lens may scarcely display their enzyme activities.

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The time courses of the glycyrrhizin and isoliquiritigenin glycoside contents in the thickening roots of licorice, Glycyrrhiza glabra L., have been determined. The glycyrrhizin content in 1-year-old roots rapidly increased from October to November, whereas the isoliquiritigenin glycoside content increased up to October. In 3-year-old plants, although the isoliquiritigenin glycoside content rapidly increased from June to July, the glycyrrhizin content did not show any significant increase from May to August. The glycyrrhizin content increased during the senscence of the aerial parts as well as during the early stage of shoot elongation. The incorporation of [¹⁴C]mevalonic acid into the glycyrrhizin fraction by the root segments was high in May, June and September, and low in August and winter. These results indicated that the biosynthesis of glycyrrhizin is differently regulated from that of isoliquiritigenin glycoside in the thickening root of G. glabra.

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The extracts of Coptidis japonica (rhizoma), Eugenia caryophyllata (flower), Rheum palmatum (rhizoma), Magnolia officinalis (cortex) and Rhus javanica (galla rhois) potently inhibited the grow of Helicobacter pylori (HP). However, these herbal extracts showed no inhibitory effect on HP urease except Galla rhois. Among the components separated from active herbal extracts by silica gel column chromatography, the inhibitory effects of decursinal angelate and decursion on the growth of HP were the most potent, followed by magnolol, berberine, cinnamic acid, decursinol and gallic acid. Minimum inhibitory concentrations (MICs) of decursin and decursinol anglate were 6-20 μg/ml

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To search for possible anti-tumor-promoters, we carried out the primary screening of seventeen deterpenes (1-17) isolated from the resinous wood of Excoecaria agallocha (Euphorbiaceae) using an in vitro synergistic assay system. Of these diterpenes, ent-16-hydroxy-3-oxo-13-epi-manoyloxide (5), (13R, 14R)-ent-8α, 13;14, 15-diepoxy-13-epi-labda-3β-ol (8) ent-3β-hydroxy-15-beyeren-2-one (10) and ent-15-hydroxy-labda-8(17), 13E-dien-3-one (14) exhibited significant inhibitory effects on Epstein-Barr virus (EBV) activation induced by the tumor promoter, 12-O-tetradecanoylphorbol-13-acetate (TPA). Furthermore, 10 exhibited remarkable anti-tumor-promoting activity in vivo on a two-stage carcinogenesis test of mouse tumor using 7, 12-dimethylbenz[a]-anthracene (DMBA) as an in;tiator and TPA as a promoter.

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Fukinolic acid (1) and cimicifugic acid A (2), caffeic acid analogs, as well as rosmarinic acid (3) and caffeic acid (4) showed inhibition on seed germination and seeding growth. The potency of 1 and 2 was comparable with that of 3. Compounds 1 and 2 also showed strong inhibitory activites as well as 3 and 4 on α-amylase. The activity of 1 was higher than that of acarbose used as a positive control, and its 50% inhibitory concentration (IC₅₀) was 2.41×10^-5 M. Compounds 1 and 2 also showed inhibitory activities strong as 3 and stronger than 4 on carboxypeptidase A. The activities of 1 and 2 were higher than that of 1, 10-phenanthroline used as a positive control.

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In the actue phase reaction, hepatocytes in the liver are activated and increase the plasma levels of acute phase reactants. Our previous study has shown that plasma sialic acid, an acute phase reactant, was increased following exposure of mice to UV-B radiation. Plasma sialic acid is derived from many plasma components. To clarify the type of plasma sialic acid that is increased by exposure to UV-B radiation, we performed two-dimensional electrophoresis and staining for sialic acid. Consequently, the increases in haptoglobin and hemopexin were marked and 90% or more of the increased sialic acid was derived from these two glycoproteins after exposure to UV radiation. The increase in α₁-acid glycoprotein levels was slight and did not contribute to the total increase in plasma sialic acid after exposure to UV radiation. Plasma levels of several proteins including antichymotrypsin (ACT), were reduced following exposure to UV radiation. The discrepancy between our results and published ones regarding ACT levels are discussed in terms of the type of cytokine.

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Effect of a suitable combination of 1-naphthaleneacetic acid (NAA) and cytokinin N-(2-chloro-4-pyridyl)-N'-phenylurea (4PU30) concentrations, regarding organ differentiation and dihydroisocoumarin production, was examined in Hdrangea macrophylla var. thunbergii callus cultures. The callus cultured in a Linsmaier-Skoog medium containing 10^-5 M NAA and 10^-5 M 4PU30 under a light condition gave the highest level for callus growth, shoot formation, and phyllodulcin 8-O-glucoside content.

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