A series of the process of neutrophil extravasation induced by topical application of leukotriene B₄ (LTB₄) or formyl-methionyl-leucyl-phenylalanine (fMLP) on microvasculature of the hamster cheek pouch can be divided into five steps; I) rolling on the venular endothelium, II) adhesion on the endothelium, III) passage between the endothelial cells, IV) staying in the venular wall, V) migration from the venular wall to the interstitial space. In step II, topical application of chemoattractants on the microvasculature caused an increase in the number of neutrophils adhered to the venules. In step III, the size of the adhered neutrophils became gradually smaller and finallly disappear from the vascular lumen, as they were observed on the monitor screen. Over 80-90% of the adhered neutrophils passed through the endothelial cells. The whole process from step II to III took about 7 minutes. In step IV, the neutrophils which passed through the endothelial cells stay for about 30 minutes in the venular wall. In step V, neutrophils penetrated the basement membrane and migrated into the interstitial space.
Step II and III were suppressed by a cyclic AMP phosphodiesterase inhibitor, fibronectin inhibitor and cytochalasin B. From these results, it was suggested that chemoattractant may cause the contraction of microfilament of neutrophil, and the contraction may induce the expression of adhesive glycoprotein on the neutrophil membrane. The increase of cyclic AMP in the neutrophil may inhibit the contraction of microfilament and/or the expression of adhesive glycoprotein of neutrophil. Dexamethasone did not affect the step I to IV, but suppressed the step V. Dexamethasone may inhibit synthesis and/or release of protease (s) in the neutrophil granules which degrade the basement membrane. In fact, the collagenase inhibitor suppressed the step V, although it did not the step I to IV. Thus, neutophil-derived collagenase may act on the passage of neutrophil through the basement membrane. The process of neutrophil extravasation is the chain of reaction.

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The mechanism for histamine release of bone marrow cells stimulated by the inflammatory exudate, the pouch fluid in air pouch type allergic inflammation in rats, was examined. When bone marrow cells were incubated in the medium containing dialyzed pouch fluid supernatant, histidine decarboxylase activity in the cells and histamine level in the medium were significantly increased when compared with those in bone marrow cells incubated in the medium alone. Addition of an RNA synthesis inhibitor, actinomycin D, or a protein synthesis inhibitor, cycloheximide, into the medium strongly reduced the dialyzed pouch fluid supernatant-induced increase in histamine level in the medium. Inhibitors of DNA synthesis, mitomycin C and cytosine arabinoside, reduced it partially. In addition, it was inhibited by retinoic acid, a differentiation-inducer, but was augmented by sodium n-butyrate, which induces differentiation of bone marrow cells to basophils. Without dialyzed pouch fluid supernatant, retinoic acid and sodium n-butyrate did not affect histamine production. These results suggest that the inflammatory exudate in allergic inflammation has an activity to stimulate histamine production by bone marrow cells by inducing de novo synthesis of histidine decarboxylase which is regulated by growth and differentiation of histamineproducing cells.

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The pathogenesis of ethanol-induced gastric mucosal damage in the rat is not fully understood. The effect of ethanol on the gastric submucosal microvessels and the possible role of arachidonic acid metabolites were studied. Intragastric administration of 5ml of 30% ethanol for 3min caused mucosal lesion of 32.6 ± 2.2% of the glandular stomach, which was attributed to congestion and cessation of mucosal capillary blood flow spreading from the collecting venule. This lesion was inhibited to 18.0±3.6% by pretreatment of AA-861 (80 mg/kg, p.o.) . The immunoreactive-leukotriene C₄ (i-LTC₄) content in the gastric wall was 0.6±0.1 ng/stomac in the resting state, and was significantly increased to 4.0±0. 5 ng/stomach after 30% ethanol in the gastric lumen. Intragastric administration of 1.0 M NaCl caused increase in PGE₂ levels in the gastric lumen. The electrical activity of the gastric smooth muscle was also suppressed by 1.0 M NaCl solution.
It may be concluded that endogenous i-LTC₄ generated in the gastric wall after 30% ethanol constricts the collecting venule and induces the congestion of the mucosal blood flow and the lesion suppresses by increased PGE₂ for suppressed smooth muscle contraction.

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It is generally accepted that anti-inflammatory drugs (NSAID) act by inhibiting the synthesis of prostaglandin (PGs) . However, salicylic acid, the most ancient of these drugs, is an ineffective cyclooxygenase inhibitor, but is equipotent with aspirin in antiinflammatory activity, we have now investigated the effect of such salicylates as aspirin (ASA), salicylic acid (SA), methyl salicylate (MS) and glycol salicylate (GS) on experimental acute inflammation.
On rat paw edema induced by carrageenin, all salicylates showed the inhibitory effect in oral administration that was weak at 1 hr, but potent after 2 hrs. In local injection, all salicylates did not show the significant inhibition on paw edema, but in skin application as ointment, these drugs inhibited signi-ficantly the paw edema. The order of inhibitory activity on edema was ASA>SA≥MS≥GS. On guinea pig skin erythema induced by UV irradiation and arachidonic acid, all salicylates inhibited significantly only in early phase, but did not inhibit PGE₂-induced erythema in all phase. The order of inhibitory activity on erythema was ASA>SA>GS≥MS.
This mode of action of salicylates was the same as that of general NSAID of cyclooxygenase inhibitors. Collagen- or arachidonic acid-induced aggregation of rat platelets and acute death of rabbits by arachidonic acid i.v. injection were inhibited by aspirin, whereas other three salicylates were inactive. A23187-, fMLP- and zymosan-induced active oxygen generation of rat leucocytes was not inhibited by all salicylates.
It may be suggested from these results that except a partial action of ASA, salicylates act as SA in viva and the anti-inflammatory activity of SA is due to inhibition of PGs production, and the mechanisms are not the inhibition of the platelets and leucocytes functions, but the unknown action.

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We examined the effects of alpha-1-proteinase inhibitor (α₁-Pi) in physiological concentrations on polymorphonuclear leukocyte (PMN) migration in vitro using the multiple blind well assay system.
Alpha-1-proteinase inhibitor had both stimulatory and inhibitory effects on cell migration depending on its concentration. The inhibitor was active in 1) inducing directed locomotion (chemotaxis) in concentrations of 0.02, 0.2 mg/ml and non-directed locomotion (chemokinesis) in concentrations of 0.02, 0.2 and 2 mg/ml, with maximum potency in both cases at 0.2 mg/ml (corresponding to the normal alveolar surface level in the lung), but 2) inhibiting chemotactic responsiveness to known chemoattractants at 2 and 10 mg/ml (corresponding to normal and inflammatory blood levels, respectively) in order of potency.
These results suggest that α₁-Pi may play a unique role in regulating inflammatory processes especially in the lung, through its stimulatory and inhibitory effects depending on its concentration.

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Bucillamine [N- (2-mercapto-2-methylpropanoyl) -L-cysteine, Rimatil ^(R) ] is a new slow-acting antirheumatic drug developed in Japan. The chemical structure of Bucillamine is similar to that of D-penicillamine except that it has two rather than one SH-bond in the molecule. As it is generally accepted that the SH-bond plays a role in the antirheumatic effect of D-penicillamine, the effectiveness of Bucillamine on rheumatoid arthritis has been proved in several studies.
We administerd Bucillamine to 87 cases of rheumatoid arthritis patients for about 5 years, during which it became apparent that Bucillamine has the nephrotoxic potential to cause proteinuria. The frequency of bucillamine-induced proteinuria reached 12.6% in our study. Males were more susceptible to proteinuria than females (20.0% vs 11.1%), but its occurrence was not related with the dosage of bucillamine, disease duration, or the anatomical stage of disease.
Other side effects, such as eruptions, itching, oral aphtha, malaise, and dysgeusia, also occurred, but no patient with proteinuria showed skin symptoms and/or dysgeusia.
As bucillamine has the potential to cause proteinuria, similar to other antirheumatic drugs such as D-penicillamine and gold, special attention must be paid to renal involvement.

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It is believed that circulating immune complexes (IC) play pathogenic roles by affecting lymphocyte and/or monocyte function in type III allergy. We studied the influences of heat aggregated human IgG (AHG), as a model of IC, on the proliferation of mononuclear cells in respect of difference in the involved IgG subclasses. IgG 1 and IgG 2 subclass of AHG (AHG1, AHG 2) suppressed significantly the proliferation of mononuclear cells without mitogens. Proliferation of mononuclear cells stimulated by concanavalin A (Con A) was significantly suppressed not only by AHG 1 and AHG 2 but also by AHG 4. Flow cytometric analysis indicated that unstimulated lymphocytes or monocytes could bind more AHG 1 and AHG 2 than AHG 3 and AHG 4. Since results coincided with the results mentioned above, unstimulated mononuclear cell proliferation was suppressed through the binding of AHG on the surface of mononuclear cells. AHG suppression of mononuclear cells stimulated by Con A was effectively inhibited by an addition of indomethacin and/or catalase.
These results indicated that prostaglandin and/or H₂O₂ might play an important role in inhibition of proliferation of mononuclear cells by AHG. Taken together, IC play a different role in immune network by affecting lymphocytes or monocytes according to difference in IgG subclasses.

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Quantitative analysis of thromboxane (TX) levels in vivo is a useful approach to clerify clinical feature of cardiovascular disease. TXA₂ is metabolized to TXB₂ at nonenzymatic. Consequently plasma TXB₂ level is fluctuated by TXA₂ which was produced from platelets during blood collection. 11-dehydro-thromboxane B₂ (11 DT) is a major metabolite of TXB₂ and not producedby the stimulation of platelets during blood collection.
We studied a simple and rapid extraction method for 11 DT. 11 DT was extracted from sample by the addition of octadecylsilyl silica powder (80 mg/ml) suspended in 40% aqueous EtOH followed by the fractionation using silica open minicolumn BOND ELUT Si (Analytichem International, Inc., Harbor City, USA) solutions in three different composition of acetonitrile, chloroform and acetic acid were used as eluents. These fractions were quantitated by radioimmunoassay (NEN, Boston USA) .
11 DT was recovered 76.1±2.3% (n=10) as closed form using the both of open and closed form of [³H] -11 DT as tracer. Concentrated plasma 11 DT obtained by this method in normal subject was less than 5.2 pg/ml (n=130, male; n=64 age 1948, female; n=66 age 18-48) . There was no sexual difference in plasma 11 DT level by this method. Plasma 11 DT levelwas not so high as that of TXB₂ which was directly influenced by the platelet release during blood collection. Serum 11 DT level was 2, 400±500 pg/ml (n=10) which is higher than that in plasma (7.1±1.9 pg/ml) .
In conclusion, the technical advantages of this method can be summarized into two major points, simplicity and requiring small volume of sample.

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The effect of recombinant human basic fibroblast growth factor (rhbFGF) on wound healing was studied biochemically and histologically in a, rat spongeimplantation model. Administration of 2 or 10 μg/rat of rhbFGF to a sponge piece increased the protein and DNA contents of the sponge as well as the wet weight, 1 and 2 weeks after the implantation. One week after the implantation of the rhbFGF-pellet, increases in capillary formation and infiltration of cellular and fibrillar components were histologically observed. The hemoglobin content of the sponge piece also significantly increased, suggesting that the hemoglobin content is a good biochemical marker for angiogenesis and wound healing process. The collagen content of rhbFGF-containing pellet was not significantly different from that of the control.
The effect of rhbFGF on the hemoglobin content was totally abolished by rhbFGF-neutralizing antibody. The results indicate that rhbFGF exhibits its angiogenic action in vivo and suggest that it accelerates wound healing.

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Effect of Syosaiko-to, the boiling extract of a mixture of 7herbs, on arachidonic acid metabolism was examined by using porcine pulmonary artery endo-thelial cells in culture (PPAEC) . Both cyclooxyge-nase derivatives, including 6-keto-PGF 1α, and li-poxygenase derivatives released into cullture medium, were decreased during 24 hour-incubation with 500 μg/ml of Syosaiko-to by HPLC analysis. The decrease in thromboxane B₂ and lipoxygenase derivatives, 5-HETE, 12-HETE and 15-HETE, was more remarkable than that in 6-keto-PGF 1α. Thrombin-or bradykinin-stimulated PGI₂ production by PPAEC monolayer, however, was increased after 24 hour-incubation with Syosaiko-to, compared with control.
Our experimental results show that Syosaiko-to suppresses the production of arachidonic acid meta-bolites, especially thromboxane B₂ and lipoxygenase derivatives, by PPAEC, supporting the antiinflamma-tory action of Syosaiko-to.

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The pharmacokinetics of ampiroxicam, a prodrug of piroxicam, were investigated by a crossover study involving 19 healthy normal subjects which was conducted over two different phases.
In the 1st phase of the study, the pharmacokinetics were compared between a dose of 27 mg and 20 mg of ampiroxicam and in the 2 nd phase, doses of 27 mg and 13.5 mg ampiroxicam were compared with a dose of 20 mg of piroxicam with the results sum-marized below. Both the C_max and AUC following administration of ampiroxicam were dose-dependent. The ampiroxicam 27 mg group was found to be slower in the absorption rate and slightly lower in C_max than the piroxicam 20 mg group.
But the ADC_s of the drug groups were equal indicating that ampiroxicam and piroxicam were bioequivalent. The half-lives of ampiroxicam and piroxicam were approximately 40 hours. Neither adverse reactions nor laboratory abnormalities were noted during the present study.

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Lobenzarit (CCA) has been widely used in Japan for the treatment of RA as one of DMARDs. Considerable patient to patient variation of its effectiveness is observed with unclarified mechanism. In this study, clinical efficacy of lobenzarit (CCA) and alteration of immunological parameters during 6 months of treatment were examined in 22 patients on early stage of RA who fulfilled the revised ARA criteria. The patients received no immuno-modulating agents except CCA and those taking more than 5 mg/day of prednisolone were excluded from the study. Alteration of lymphocyte subsets measured by using monoclonal antibodies and the fluorescence-activated cell sorter, PHA-stimulated cytokine (IL-2 and gamma-IFN) production, serum levels of immunoglobulins and various auto-antibodies were monitored in conjunction with clinical assessment during the course of treatment.
The patients were clinically classified into responders (10/22) and nonresponders to CCA (12/22) . Those who responded well to CCA showed normalization of CD20-positive B cells in association with decreased levels of serum immunoglobulins, immune complexes, and antibodies to double-stranded DNA. These patients showed no significant alteration of T cell subsets and cytokine production prior to and after CCA therapy. In contrast, nonresponders demonstrated to be defective in cytokine production throughout the treatment.
These results may indicate that CCA exerts its anti-rheumatic effect through B cell level.

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