Mast cell degranulation and its inhibition by an anti-allergic agent tranilast. An electron microscopic study

Degranulation of IgE-sensitized rat mast cells by antigen was studied quantitatively in vitro and in vivo by electron microscopy. The inhibition of this degranulation by an anti-allergic drug, N-(3,4-dimethoxycinnamoyl)anthranilic acid (Tranilast), was also examined both in vitro and in vivo. In the in vitro study using peritoneal mast cells, alteration of the granules, cavity formation by fusion of the perigranular membrane and granule discharge due to fusion of the cavity membrane with the cell membrane were observed and were accompanied by histamine release. Scanning electron microscopy disclosed the extrusion of smooth, round bodies from pores formed on the cell surface. In the in vivo study of passive cutaneous anaphylaxis (PCA), the characteristic features of mast cell degranulation were obvious 5 min after the injection of antigen; leakage of dye increased progressively from 5 to 30 min but was not found at 6 h. From quantitative analysis of the substructure of mast cells, it was demonstrated that degranulation of IgE-sensitized mast cell induced by antigen was achieved by sequential exocytosis both in vitro and in vivo. Tranilast inhibited these changes to a remarkable extent and it was concluded that the inhibition of mast cell degranulation by this drug might play an important role in anti-allergic treatment.     

Unusual solvent effect on protease activity and effective optical resolution of amino acids by hydrolytic reactions in organic solvents

Summary The catalytic activities of -chymotrypsin, subtilisin Carlsberg, and subtilisin BPN' for hydrolysis of amino acid esters in acetonitrile-water were unusually dependent on the solvent composition. The products obtained as precipitates in high concentrations of acetonitrile were L-amino acids of high optical purities, and effective optical resolution of amino acids was achieved.     

A novel opioid peptide, leumorphin, acts as an agonist at the kappa opiate receptor

The primary structure of the common precursor of porcine beta-neo-endorphin and dynorphin (preproenkephalin B) has shown the existence of a third leucine-enkephalin (leu-enkephalin) sequence with a C-terminal extension of 24 amino acids. This nonacosapeptide, named leumorphin, was approximately 70 times more potent than leu-enkephalin in inhibiting the contraction of the myenteric plexus-longitudinal muscle preparation of the guinea pig ileum. This action of leumorphin, like those of beta-neo-endorphin and dynorphin, was antagonized less effectively by naloxone than that of leu-enkephalin, but more effectively by Mr2266, an antagonist relatively specific for the kappa type opiate receptor. The inhibitory action of leumorphin or beta-neo-endorphin on the contraction of the guinea pig ileum muscle strip was reduced in a dose-dependent manner by pretreatment with dynorphin and vice versa. Leumorphin as well as beta-neo-endorphin and dynorphin inhibits the contraction of the rabbit vas deferens which is known to have only the kappa type opiate receptor. This action was also effectively antagonized by Mr2266. It is concluded that leumorphin has potent opioid activity and acts at the kappa receptor, like other opioid peptides derived from preproenkephalin B.     

Mode of antitumor action of recombinant human tumor necrosis factor on the sarcoma Meth A transplanted in the mouse

The mode of antitumor action of rHu-TNF was elucidated in BALB/c mice bearing Meth A fibrosarcoma 7 days after transplantation with respect to time course, dose-response relationships and selectivity of the effects. The maximal cytotoxic effect on tumor cells revealed by inhibition of DNA synthesis and maximal lesional effect on tumor vasculature revealed by change in blood pool-size in the tissue were detected at 30 min and I h after administration of rHu-TNF, respectively. The dose-response relationship between cytotoxic and tumoricidal effects of rHu-TNF was irrespective of administration route. ED₅₀s of these antitumor effects afteri.v. administration of rHu-TNF were about 50 times as high as ED₅₀s afteri.t. administration. ED₅₀ ofi.t. given rHu-TNF for vascular effect was about 20 times as high as that for cytotoxicity while ED₅₀ ofi.v. rHu-TNF for vascular effect was only 2–3 times as high as that for cytotoxicity. The whole body autoradiographies with [¹²⁵I] HSA giveni.v. to see the blood influx into tumor tissue and [¹⁴C]thymidine given i.v. to see DNA synthesis in the whole body after administration of rHu-TNF revealed that the distribution of radioactivity was markedly changed in the tumor alone without any detectable change in other whole body tissues.In conclusion, thein vivo antitumor effect of rHu-TNF giveni.t. ori.v., appears to be exerted through the direct action on Meth A sarcoma rather than indirectly on tumor vasculature. Under present conditions, the effect of rHu-TNF in the whole body tissues seems rather selective on cells and vasculature of the tumor.     

Electron microscopic radioautographic study of the localization of an anti-allergic agent, Tranilast, in rat mast cells.

We have previously reported that Tranilast, an anti-allergic agent, was rapidly taken into the cytoplasm of rat mast cells in vitro by means of light microscopic radioautography. The present study was performed at the electron microscopic level to elucidate the fine localization of this agent in the mast cells. The results revealed that the number of radioautographic silver grains in the cells increased by the incubation with 3H-labelled Tranilast for 0 to 60 min. and that many silver grains were localized on the specific granules, especially on the perigranular membranes. These results suggest that the mode of inhibitory action of mast cell degranulation by Tranilast is related to the specific localization of this agent on the perigranular membranes.     

Effects of estradiol and testosterone on the synthesis,expression and degradation of androgen receptor in human uterine endometrial fibroblasts

The mechanism of known receptor-mediated androgen effects on the endometrial stroma was studied in endometrial fibroblasts derived from human uterus. 17-Estradiol (E) induced the expressions of androgen receptor (AR) mRNA, and predominantly increased the level of testosterone-binding sites (TBS) in uterine endometrial fibroblasts. The effect on the level of dihydrotestosterone-binding sites (DHTBS) was similar but smaller. This result suggests that the AR mRNA expressed might encode TBS, but probably not DHTBS. The TBS level increased by estrogen was down-regulated by testosterone (T) + E, but the AR mRNA expression increased by E was not down-regulated by E + T in the fibroblasts. Although the synthesis rate of AR was slightly increased (p<0.05) by E alone or E + T, the degradation rate of AR was significantly accelerated (p<0.05) by E + T in the fibroblasts. This result suggests that T might stimulate the metabolic rate of TBS, but does not inhibit the synthesis rate of AR mRNA to TBS in endometrial fibroblasts.     

Extra-weak chemiluminescence of drugs XV. Method for determining stability of Toki-shakuyaku-san extract granules

The purpose of the study was to evaluate the quality of Toki-shakuyaku-san extract granules (TJ-23) using chemiluminescence (CL). A linear relationship was obtained between the log value of the CL of TJ-23 and the reaction temperature. An excellent correlation (r= 0.999) was found between the slope of this curve (ΔA) and the colour intensity due to the browning reaction occurring at the early stage of the Maillard reaction.     

Acidiphilium aminolytica sp. nov.: An acidophilic chemoorganotrophic bacterium isolated from acidic mineral environment

Acidiphilium aminolytica is proposed for a species of the genusAcidiphilium. Acidiphilium aminolytica can be phenotypically differentiated from all other species of the genusAcidiphilium. The seven strains of this species that have been studied are Gram-negative, aerobic, mesophilic, non-sporeforming, motile, and rod-shaped bacteria. They grow between pH 3.0 and 6.0, but not at pH 6.5. They yield positive results in tests for hippuric acid hydrolysis, catalase and urease production. Oxidase, esculin hydrolysis, and -galactosidase tests are negative. They can used-glucose,d-galactose, inositol, sorbitol,l-lysine,l-glutamate,l-arginine, -alanine,dl-4-aminobutyrate,dl-5-aminovalerate, sperimine, or diaminobutane as a sole carbon source, but cannot use elemental sulfur and ferrous iron as an energy source. The DNA base composition is 58.7–59.2 G+C mol%. The major isoprenoid quinone is ubiquinone with ten isoprene unit (Q-10). The major fatty acid is the C_18:1 fatty acid. Two ornithine amide lipids, the C_18:1 fatty acid esters of -N-3-hydroxystearylornithyltaurine and -N-3-hydroxystearylornithine, are detected as the polar aminolipid. DNA relatedness between this species and the other species ofAcidiphilium, the generaAcidomonas, andAcidobacterium was 29 to 2%. These results indicate, that this new species should be placed in the genusAcidiphilium. The type strain (strain 101) ofA. aminolytica is JCM 8796.     

Total DNA 5-methylcytosine level of rice calli derived from protoplasts is independent of regeneration ability

To study the roles of m⁵C in the differentiation of rice calli derived from protoplasts (protoclones), the m⁵C level of the total DNA was analyzed using the³²P post-labeling method. The level of m⁵C in regenerable and nonregenerable protoclones was similar, as was in calli and leaves of plants regenerated from the same protoclones. Treatment with 0.5 mM 5-azacytidine caused significant reduction of the level of m⁵C and of the regeneration frequency of callus. Significantly increased m⁵C levels were observed during prolonged culture.