Detection of platelet-activating factor in exudates of rats with phorbol myristate acetate-induced pleurisy

PAF-likely activity, detected as aggregation of washed platelets, was found in the exudate of rats with pleurisy induced by phorbol myristate acetate (PMA, 1 nmol). At 30 min after the injection of PMA, 400-500 pg of PAF was detected in the pleural exudate. An extract of the exudate was made and analysed by HPLC and by rabbit platelet aggregation. The activity was characterized as that of PAF as a result of the inhibition seen with the PAF-antagonist CV-3988 and the loss of activity by treatment with phospholipase A2. Indirect evidence was previously reported in that CV-3988 suppressed the pleural fluid accumulation in the pleurisy induced by PMA. Taken together these facts it indicates that PAF could be an important mediator of acute inflammation, especially of the plasma exudation resulting from an increase in vascular permeability. Evidence that pleural cells produce PAF was also examined in an in vitro experiment. PAF was found in the supernatant and cellular fractions of the incubation mixture of the pleural cells from normal rats when stimulated by PMA (1 microM) or A23187 (5 microM), and the results indicate that the pleural cells produce PAF and release a portion of it.

Roles of kallikrein-kinin system in acute inflammation: studies on high- and low-molecular weight kininogens-deficient rats (B/N-Katholiek strain)

Carrageenin-induced paw edema in HMW- and LMW-kininogens-deficient rats was significantly less than that in normal rats. There are three kininogens, HMW-, LMW- and T-kininogens, in normal rat plasma, but B/N-Katholiek rat plasma contains only T-kininogen. The pretreatment with captopril, a kiniase II inhibitor, enhanced paw swelling of normal rats, but not that of the deficient rats, indicating that bradykinin released from HMW-kininogen may have a role for the swelling but T-kinin may not be released in this inflammation.

[Toxicological evaluation of an in vitro culture of mouse embryos; effect of non-carcinogenic mutagens for the development of embryos]

Short term drug toxicities were investigated using cultures of mouse embryos in the early stage of development. These embryos were collected at the two- or eight-cell stage. They were exposed to bleomycin (B1) or 6-mercaptopurine (MP) for 24 hr, thereafter, they were grown in BMOC-3 medium without these agents until the blastocyst stage. Total culturing period was 72 hr for the two-cell embryos and 48 hr for the eight-cell embryos. At the end of the culture periods, the number of cells, mitotic index and frequencies of sister chromatid exchange in these embryos after these exposures were unaltered. However, the death rate of embryos was elevated by the exposure to either B1 or MP. These agents are regarded as non-carcinogenic mutagens; therefore, it is suggested that these compounds are lethal to the embryos through an induction of mutation.

Characterization of kininogen deficiency of Brown Norway rat mutant Katholiek strain

A deficiency in the plasma kallikrein-kinin system of Brown Norway rat mutant Katholiek strain (B/N-Ka), first reported by Damas et al. was further characterized. The prolonged activated partial thromboplastin time (APTT) of B/N-Ka rat plasma was corrected by an addition of rat HMW-kininogen, indicating B/N-Ka rat is deficient in HMW kininogen. The study of kinin-release of plasmas of the three strains of rat (B/N-Ka, B/N Ki and SD) by several kininogenases expressed that B/N-Ka rat is deficient in LMW kininogen, in addition to HMW kininogen deficiency. The plasmas of the three strains of rat were gel-filtered through Sephacryl S-200 gel and profiles of kinin-release of the fractions were examined by several kininogenases. The result demonstrated that normal rat plasma contains three kinds of kininogen (HMW and LMW kininogens, and T-kininogen), and B/N-Ka plasma contains only T-kininogen. B/N-Ka rat plasma demonstrated T-kininogen antigen but no HMW kininogen by the study of immunodiffusion using their antisera raised in rabbits.

Phorbol myristate acetate-stimulated release of cyclooxygenase products in rat pleural cells: derivatization of prostaglandins with 9-anthryldiazomethane for fluorometric determination by high performance liquid chromatography

White cells were collected from the wash of rat pleural cavity after exsanguination. The incubation mixture of the pleural cells with 1 microM phorbol myristate acetate (PMA) was extracted with acidified ethanol and purified with a Sep-pak C18. The resultant fraction containing prostaglandins (PG) and thromboxane (TX) was allowed to react with 9-anthryldiazomethane (ADAM). After removing contaminants and degraded reagent by silica gel Sep-pak, samples were applied to reversed phase high performance liquid chromatography of octadecylsilyl silica gel and monitored by a fluorescent detector. ADAM derivatives of the authentic PGD2, PGE2, PGF2 alpha, 6-keto-PGF1 alpha, 6-keto-PGE1, TXB2, 15-keto-PGE2, 13,14-dihydro-15-keto-PGF2 alpha and 13,14-dihydro-15-keto-PGE2 showed linear regression lines of peak heights within a range of 0.5-25 ng. By using this method PGD2, 6-keto-PGF1 alpha and TXB2 were detected in the incubation mixture of the rat pleural cells with PMA. The result clarified the origin of these PGs and TX found in the exudate of rat pleurisy induced by PMA. ADAM method for HPLC with a help of clean-up by Sep-pak could be a useful tool for detection of a series of arachidonate metabolites in biological materials.

Involvement of histamine in vascular permeability increase of the rat pleurisy induced by phorbol myristate acetate

Rat pleurisy was induced by an intrapleural injection of 1 nmol (0.1 ml) of phorbol myristate acetate (PMA). Accumulation of pleural fluid peaked at a volume of 1 ml at 1 hr, and exudation rate peaked at 30 min when measured by the amount of dye leaked into the pleural cavity during 20 min. Histamine contents decreased in the pleural cell pellets markedly at 30 min and increased in the supernatant fluid simultaneously, reflecting histamine release that occurred in 30 min after PMA. Pretreatment with mepyramine maleate or methysergide 30 min prior to the PMA-injection suppressed the fluid volume significantly. The result indicates that there are involvements of 5-hydroxytryptamine and the H1-receptor of histamine in the vascular permeability increase at the early stage of PMA-pleurisy.

Involvement of arachidonic acid metabolites in acute inflammation: detection of 6-keto-PGF1 alpha, thromboxane B2 and PGD2 in rat pleurisy induced by phorbol myristate acetate

Rat pleurisy was induced by intrapleural injection of phorbol myristate acetate (PMA), a known tumor promotor and a component of croton oil. Pleural fluids at 30 min and 1 hr after PMA-injection were collected and arachidonic acid metabolites in the fluids were measured by RIA or bioassay after fractionation through reversed phase HPLC using an ODS column. The major metabolites found in the pleural fluid were 6-keto-PGF1 alpha, TXB2 and PGD2, with a small amount of PGE2. Pretreatment with 10 mg/kg indomethacin suppressed the pleural fluid accumulation and also reduced the amount of the above metabolites to the basal levels. Treatment with OKY-046, a novel thromboxane synthetase inhibitor, reduced the level of TXB2 completely, but had no effect on those of 6-keto-PGF1 alpha and PGD2, and it had no effect on pleural fluid accumulation either. The results may indicate that PGI2 plays a role for the vascular permeability increase in the early phase of pleurisy.

Identification of T-kininogen in high and low molecular weight kininogens deficient rat (brown Norway Katholiek strain)

Kinin release in Brown Norway Katholiek (B/N-Ka) rat plasma was compared with those of Brown Norway Kitasato and Sprague-Dawley rats by treating with rat plasma kallikrein, rat urinary kallikrein, snake venom kininogenase and trypsin. B/N-Ka rat plasma yielded no detectable amount of kinin by either plasma kallikrein, urinary kallikrein or snake venom kininogenase, but yielded variable amount of kinin by trypsin. The released kinin was proved to be isoleucylseryl-bradykinin by high performance liquid chromatography and bioassay profiles. B/N-Ka rat plasma formed a precipitation line against antiserum to T-kininogen, but no line against antiserum to HMW kininogen-light chain.

Rat plasma high-molecular-weight kininogen. A simple method for purification and its characterization

High-molecular-weight kininogen has been isolated from rat plasma in three steps in a relatively high yield. The purified preparation gave a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis in the absence and presence of 2-mercaptoethanol, and the apparent Mr was estimated as 100,000. On incubation with rat plasma kallikrein, rat high Mr kininogen yielded a kinin-free protein consisting of a heavy chain (Mr = 64,000) and a light chain (Mr = 46,000), liberating bradykinin. The kinin-free protein was S-alkylated, and its heavy and light chains were separated by a zinc-chelating Sepharose 6B column. The amino acid compositions of rat high Mr kininogen and its heavy and light chains were very similar to those of bovine high Mr kininogen and its heavy and fragment 1.2-light chains, respectively. A high histidine content in the light chain of rat high Mr kininogen indicated the presence of a histidine-rich region in this protein as in bovine high Mr kininogen, although this region was not cleaved by rat plasma kallikrein. Rat high Mr kininogen corrected to normal values the prolonged activated partial thromboplastin time of Brown-Norway Katholiek rat plasma known to be deficient in high Mr kininogen and of Fitzgerald trait plasma. The kinin-free protein had the same correcting activity as intact high Mr kininogen. Rat high Mr kininogen also accelerated approximately 10-fold the surface-dependent activation of rat factor XII and prekallikrein, which was mediated with kaolin, amylose sulfate, and sulfatide. These results indicate that rat high Mr kininogen is quite similar to human and bovine high Mr kininogens in terms of biochemical and functional properties.

Cleavage of des-Arg9-bradykinin by angiotensin I-converting enzyme from pig kidney cortex

Fast and very slow hydrolyses of des-Arg9-bradykinin and angiotensin II by angiotensin I-converting enzyme were detected by high performance liquid chromatography. The Michaelis constants of the enzyme, Km values, for des-Arg9-bradykinin and bradykinin were found to be 0.24 mM and 4.4 microM, and the maximum velocities, Vmax values (mumol . min-1 . mg protein-1) for these compounds to be 3.24 and 0.34, respectively. The enzyme also hydrolyzed Z-Gly-Pro-Gly-Gly-Pro-Ala to a tripeptide that was identified as dansyl-Gly-Pro-Ala by TLC on polyamide. These observations show that the enzyme hydrolyzes the peptides at the bond before the prolyl residue in the penultimate position.

Demonstration of arginyl-bradykinin moiety in rat HMW kininogen: direct evidence for liberation of bradykinin by rat glandular kallikreins

The amino acid sequence around kinin moiety in rat High-Molecular-Weight (HMW) kininogen was determined by isolating a peptide containing bradykinin after cyanogen bromide treatment of the purified kininogen as follows; NH2-Thr-Ser-Val-Ile-Arg-Arg-Pro-Pro-Gly-Phe-Ser-Pro-Phe-Arg-Ala-Pro-Arg- Val-Lys-Lys-. The data indicated that rat HMW kininogen contains the arginyl-bradykinin moiety, instead of lysyl-bradykinin. Kinins liberated from rat HMW kininogen by rat urinary and submaxillary kallikreins were identified to be bradykinin, not arginyl-bradykinin.

Demonstration of the third kininogen in high and low molecular weight kininogens-deficient Brown Norway Katholiek rat

A gel filtration profile of the plasma of Brown Norway Katholiek (B/N-Ka) rat was compared with those of B/N-Kitasato (B/N-Ki) and Sprague-Dawley (SD) rats. In the chromatograms of B/N-Ki and SD rat plasmas, high-molecular weight (HMW) kininogen was eluted together with pre-kallikrein. In lower molecular weight fractions, there were two kininogens, one of which released kinin by urinary kallikrein, snake venom kininogenase (SVK) and trypsin, and the other released kinin only by trypsin. In the chromatogram of B/N-Ka rat plasma, there was no fraction which released kinin by plasma kallikrein, urinary kallikrein or SVK. However, the kinin-release only by trypsin was found in the lower molecular weight fraction, which corresponds to the third peak of kininogen in the chromatograms of B/N-Ki and SD rat plasmas. These results indicate that B/N-Ka rat plasma is deficient in HMW kininogen, and also deficient in the LMW kininogen susceptible to urinary kallikrein and SVK, but it contains the third kininogen responsive only to trypsin.

Prolonged activated partial thromboplastin time and deficiency of high molecular weight kininogen in brown Norway rat mutant (Katholiek strain)

Activated partial thromboplastin time (APTT) was examined in Brown Norway (B/N) Katholiek rat, which was previously reported as high molecular weight kininogen deficient. APTT of B/N Katholiek was prolonged to 35 sec in comparison with B/N Kitasato and SD rat, showing APTT of 22-24 sec. The mixture of B/N Katholiek plasma and B/N Kitasato plasma (1:1) showed normal APTT value. B/N Katholiek plasma corrected the abnormally prolonged human coagulation factor deficient plasmas, such as XI, XII and prekallikrein deficient plasmas, while it did not correct the APTT of HMW kininogen deficient, Fitzgerald plasma. Intravenous injection of bromelain, which was previously reported to produce prolonged hypotension through the activation of factor XII to release bradykinin, induced slight effect in Katholiek rat, while in Kitasato rat it showed prolonged hypotension in similar degree as SD rat. Contents of coagulation factors in B/N Katholiek thus measured as well as the values of prekallikrein and HMW kininogen previously reported were summarized and suggested that B/N Katholiek rat could be similar deficiency as Fitzgerald trait.

Abnormalities in the contact activation through factor XII in Fujiwara trait: a deficiency in both high and low molecular weight kininogens with low level of prekallikrein

Fujiwara trait, the first case of kininogen deficiency in Japan previously reported which did not show any clinical symptom except the prolonged activated partial thromboplastin time was further examined. The activated partial thromboplastin time of the patient was corrected by addition of normal, Factor XII deficient or Fletcher plasma, but not corrected by Fitzgerald or Williams plasma. It was also corrected by addition of highly purified bovine or human high molecular weight (HMW) kininogen, but not by low molecular weight (LMW) kininogen. When total kininogen was measured as the amount of bradykinin released by trypsin, only a trace amount was detected in Fujiwara as well as Williams plasma. No immunoreactive protein against anti-human-HMW-kininogen nor anti-human-LMW-kininogen was found in Fujiwara plasma. Acetone-kaolin-activated plasma kallikrein was not generated by Fujiwara plasma. Substitution with normal plasma in various ratios showed the generation of various plasma kallikrein activities. Calculations with these activities of mixed plasma gave the prekallikrein content of Fujiwara trait plasma about 30% of the normal level. These results suggest that Fujiwara trait is very similar to Williams trait in that both plasmas were deficient in HMW and LMW kininogens with reduced content of prekallikrein.

The first cases of Fitzgerald factor deficiency in the Orient: three cases in one family

Asymptomatic, female, 56-year-old identical Japanese twins were found to have a severe abnormality in the surface-mediated intrinsic coagulation, fibrinolysis and esterolytic activity. These defects were thought to be due to the lack of Fitzgerald factor, because of the prolongations of kaolin-activated partial thromboplastin time and kaolin-activated euglobulin lysis time that were not corrected by the addition of Fitzgerald trait-plasma but were corrected to normal levels by the addition of isolated bovine high-molecular-weight kininogen, Fletcher trait-plasma or Hageman trait-plasma.