Roles of microsomal prostaglandin E synthase-1 in lung metastasis formation in prostate cancer RM9 cells.

Cyclooxygenase-2 (COX-2) is known to correlate with a poor prognosis of prostate cancer and contribute to tumor metastasis. However, the precise mechanism of this phenomenon remains unknown. We have previously reported that host stromal microsomal prostaglandin E synthase-1 (mPGES-1) appeared critical for tumor-associated angiogenesis and tumor growth. Here, we tested whether or not mPGES-1 has a critical role in lung metastasis formation of prostate cancer. Murine prostate cancer cells (RM9) were intravenously injected and lung metastasis was estimated by counting colonies in the lungs. Mice treated with a selective COX-2 inhibitor, celocoxib, were suppressed lung metastasis compared to vehicle mice. This lung metastasis formation was also reduced in mPGES-1 knockout (mPGES-1 KO) mice, compared with wild type (WT) mice. This was accompanied with reduced angiogenesis around the metastasized colonies of RM9. Plasma protein levels and metastasized lung tissue mRNA levels of vascular endothelial growth factor (VEGF) and stromal cell derived factor-1 (SDF-1) were significantly suppressed in mPGES-1 KO mice in comparison with WT mice. In addition, the expressions of matrix metalloproteinases (MMP)-9, and metalloproteinases (MMP)-2 were down-regulated in metastatic lungs in mPGES-1 KO mice. These results suggested that host mPGES-1 was essential for MMP-2 and MMP-9 up-regulation that enhances tumor metastasis. mPGES-1 appears to be critical for tumor metastasis in prostate cancers. mPGES-1 inhibitors may be useful to protect against prostate cancer metastasis.

Recruited bone marrow cells expressing the EP3 prostaglandin E receptor subtype enhance angiogenesis during chronic inflammation.

Chronic inflammation, which is characterized by the proliferation of granulation tissues, is known to be regulated by angiogenesis. Recent results suggest that bone marrow-derived (BM-derived) hematopoietic cells regulate angiogenesis in vivo. We previously reported that the angiogenesis occurring during chronic inflammation is enhanced in response to the endogenous prostaglandins (PGs) derived from an inducible cyclooxygenase-2 (COX-2). In the present study, we examined the role of BM-derived cells expressing an E-type PG receptor subtype, EP3, in sponge-induced angiogenesis. The replacement of wild-type (WT) BM with BM cells (BMCs) from green fluorescent protein (GFP) transgenic mice revealed that the formation of granulation tissue around the sponge implants developed via the recruitment of BMCs. This recruitment was enhanced by topical injections of vascular endothelial growth factor (VEGF)-A, and a VEGF-dependent increase in the recruitment of BMCs was inhibited by a COX-2 inhibitor, celecoxib. FACS analysis of the granulation tissues after treatment with collagenase revealed that the Mac-1-positive macrophage fraction was enhanced by topical injections of VEGF-A, and that this increased recruitment of Mac-1-positive BMCs was inhibited by celecoxib. Selective knockdown of EP3 performed by BM transplantation with BMCs isolated from EP3 knockout (EP3) mice reduced sponge-induced angiogenesis, as estimated by mean vascular number and CD31 expression in the granulation tissues. This reduction in angiogenesis in EP3(-/-) BM chimeric mice was accompanied by reductions in the recruitment of BMCs, especially of Mac-1-positive cells and Gr-1-positive cells. These results indicate that the recruited bone marrow cells that express the EP3 receptor have a significant role in enhancing angiogenesis during chronic proliferative inflammation.

Effects of inhaled monoethanolamine on bronchoconstriction.

We previously reported a 65-year-old man who aspirated an alkaline detergent containing 3.3% w/v (weight of solute per volume of solution) monoethanolamine (MEA) into his lungs, causing asthma-like symptoms. We presently describe the mechanism of MEA-induced bronchoconstriction according to findings in guinea pigs. In anesthetized, artificially ventilated animals, changes in airway opening pressure (P(ao)) were measured as an index of bronchoconstriction. An aerosol of 3.3% MEA solution (0.1 ml kg(-1)) inhaled through a tracheal cannula induced significantly stronger bronchoconstriction than an aerosol of potassium hydroxide (KOH) solution (0.1 ml kg(-1)) at the same pH. MEA-induced bronchoconstriction was significantly suppressed by premedication with intravenously injected atropine sulfate (3 mg kg(-1)), a muscarinic receptor antagonist, or diphenhydramine hydrochloride (10 mg kg(-1)), a histamine-H(1) receptor antagonist. MEA-induced bronchoconstriction was not enhanced by premedication with an intravenous injection of neostigmine (0.1 mg kg(-1)), an acetylcholinesterase inhibitor. When bronchoconstriction was induced by MEA, histamine concentrations in bronchoalveolar lavage fluid (BALF) were not significantly greater than in BALF after KOH-induced bronchoconstriction or in BALF after inhalation of physiologic saline. In vitro, contraction of trachea denuded of epithelium during superfusion with MEA (10 mm) was suppressed by premedication with pyrilamine maleate, a histamine-H(1) receptor antagonist, at 10 and 100 microm. Contraction of trachea denuded of epithelium during superfusion with MEA (10 mm) was suppressed by premedication with atropine sulfate at 10 and 100 microm. These results suggest that asthma-like symptoms may result partly from agonistic MEA effects at histamine-H(1) receptors and muscarinic receptors.

Are all individuals equally sensitive in the blood pressure to high salt intake? (Review article).

It has been reported that only one-third of normotensive subjects and half of hypertensive patients are salt-sensitive. Many causes of salt-sensitivity have been proposed. Our suggestion is that a reduced urinary kallikrein level may be one cause, since mutant kininogen-deficient rats, which cannot generate kinin in the urine, are salt-sensitive. Renal kallikrein is secreted by the connecting tubule cells of the kidney, which are located just distal to the macula densa or the tubuloglomerular feedback system. Excess amounts of sodium taken overflow into the distal tubules and are reabsorbed in the collecting ducts. Kinins generated inhibit sodium reabsorption in the collecting ducts. Both blacks and whites with essential hypertension excrete less urinary kallikrein than do their normotensive counterparts, but the mean value in "normotensive blacks" were not different from that in "hypertensive whites". African-Americans consume less potassium than whites. Potassium and ATP-sensitive potassium channel blockers are releasers of renal kallikrein. In a small-scale study, sodium loading caused more increase in the systolic blood pressure in urinary low-kallikrein group than in urinary high-kallikrein group. Large-scale clinical studies, under strict control of potassium intake, are needed to elucidate the relationship between salt-sensitivity and urinary kallikrein levels.

Effect of L-phenylalanine supplementation and a high-protein diet on pharmacokinetics of cefdinir in healthy volunteers: an exploratory study.

BACKGROUND: Upregulation of oligopeptide transport activity by dietary protein, certain dipeptides and amino acids has been reported in the rat intestine and a human intestinal cell line. OBJECTIVE: In this study, the pharmacokinetics of cefdinir were investigated after L-phenylalanine supplementation and a high-protein diet (HPD) in humans to explore changes in the activities of intestinal and renal oligopeptide transporters. METHODS: A normal-protein diet (NPD, 73.2 +/- 2.6 g/day), NPD + l-phenylalanine (7.5 g/day), or HPD (141.3 +/- 3.7 g/day) was given to six male healthy volunteers for 12 days followed by a single dose of cefdinir after an overnight fast in a randomized three-way crossover study with a 22-day washout. Blood and urine were collected over a 12-h period after administration of cefdinir. Concentrations of cefdinir in plasma and/or urine were measured by high-performance liquid chromatography. RESULTS: Plasma concentrations and urinary excretion of the drug did not change throughout the study. Physiological variables and laboratory values did not reveal any differences between the three periods except for serum and urinary nitrogen levels and serum triglyceride. DISCUSSION: A reason for the unchanged pharmacokinetics of cefdinir may be due to lower doses of L-phenylalanine and protein in humans than in animals when converting animal effective doses to humans. CONCLUSION: In humans, L-phenylalanine supplementation and HPD do not seem to upregulate intestinal and renal oligopeptide transport in the ranges of duration and dose examined.

Different effects of light food on pharmacokinetics and pharmacodynamics of three benzodiazepines, quazepam, nitrazepam and diazepam.

OBJECTIVE: Quazepam, nitrazepam and diazepam are administered under fed or fasted conditions for insomnia or anxiety disorder. Light bedtime food may have clinically relevant effects on the plasma levels of those drugs and hence on psychomotor performance. This study assessed the effect of light food on the pharmacokinetics and pharmacodynamics of these drugs. METHOD: Twenty-one eligible subjects were randomized to one of three groups of seven subjects: quazepam 20 mg, diazepam 5 mg or nitrazepam 5 mg. Each healthy subject took a single oral dose of the assigned drug after overnight fasting and after light food, on a separate occasion. Blood samples were collected until 72 h after dosing. The plasma samples were assayed using high-pressure liquid chromatography with spectrophotometric detection. Reaction time, critical flicker fusion test and visual analogue scales were conducted. RESULTS: The peak plasma concentration (C(max)) and area under the concentration-time curve (AUC) of quazepam with light food were 1.2-fold [90% confidence interval (CI): 1.1-1.5; P < 0.05] and 1.5-fold (90% CI: 1.3-1.9; P < 0.05) higher than that without light food, respectively. For nitrazepam and diazepam, the time to peak was delayed about 1 h in fed condition (P > 0.05). However it had no effect on their C(max) and AUC. Reaction time of quazepam with light food was prolonged at 4 and 6 h after dosing and its area under the effect-time curve from 0 to 10 h was increased (P < 0.05). CONCLUSION: Light food increased the bioavailability of quazepam and affected psychomotor performance. Light food delayed T(max) of nitrazepam and diazepam but had no effect on C(max) and AUC.

Effect of MKC-733, a 5-HT receptor partial agonist, on bowel motility and symptoms in subjects with constipation: an exploratory study.

BACKGROUND: MKC-733, a 5-HT(3) receptor partial agonist, is a novel enteroprokinetic compound. OBJECTIVE: The aim of this study was to explore the effects of MKC-733 on bowel motility and symptoms in a small group of subjects with constipation. Tolerability was also examined. METHODS: The study was conducted in a single-blind and dose-escalation manner on 14 male and female subjects with constipation aged 22-67 years. After a 1 week run-in period, subjects were treated with placebo (b.i.d.) for 1 week, and 0.2 and 0.5 mg of MKC-733 (b.i.d.) for 2 weeks sequentially. Geometric mean and per cent elimination of surrogate markers of bowel motility were measured by a radio-opaque marker technique at the end of each treatment period. They were analysed on the whole group and subgroups with low (n = 6) and high (n = 8) bowel motility based upon the geometric mean value after placebo treatment. Subjects kept diaries of their bowel habits and gastrointestinal symptoms. RESULTS: Percent elimination increased after treatment with 0.5 mg MKC-733 compared with placebo treatment in the whole group (70.4 +/- 33.5% vs. 47.1 +/- 36.6%, mean +/- SD, P < 0.05). In the low bowel motility group, both geometric mean and percent elimination increased after treatment with 0.5 mg MKC-733 compared with placebo (7.1 +/- 0.9 vs. 5.9 +/- 0.5, P < 0.05; 60.0 +/- 35.8% vs. 13.3 +/- 19.4%, P < 0.05). Stool frequency increased after the first-week treatment with MKC-733 compared with placebo (P < 0.05). Numbers of sensation of incomplete evacuation and gastrointestinal symptoms decreased to half and less after the treatment with MKC-733. No serious adverse effect was noted. CONCLUSION: Multiple doses of 0.5 mg MKC-733 improve bowel motility, which was clearly demonstrated in the subjects with decreased bowel motility. MKC-733 at the doses studied might be effective in increasing stool frequency and reduce gastrointestinal symptoms related to constipation. MKC-733 was well tolerated. Further studies will be needed to clarify efficacy and safety of MKC-733 on a larger population.

Regulatory expression of lipoxin A4 receptor in physiologically estrus cycle and pathologically endometriosis.

Expression of receptors for prostaglandin (PG) and leukotriene (LT) has been reported to detect in endometrium and smooth muscle of uterus, suggesting involvement of these arachidonic metabolites in endometrial pathology and reproductive biology. Lipoxin (LX), which is produced by lipoxygenases from arachidonic acid, has been characterized as an anti-inflammatory lipid mediator. Biological actions of Lipoxin A4 (LXA4) are mediated through the specific receptor. In order to know roles of LXA4 in female genitalia, expression of LXA4 receptor mRNA was quantified by real-time polymerase chain reaction. Significantly higher expression of the receptor was detected in endometrium and myometrium than ovary in normal rats. Expression of the receptor in endometrium was increased at stage of proestrus cycle under physiological condition. Exogenous administration of progesterone into female rats significantly reduced the expression, while administration of estradiol or pregnant mare serum gonadotropin (PMSG) did not. Both, endometrium in experimental endometriosis induced in rats and the tissues from patients with ectopic endometriosis showed a higher expression of LXA4 receptor compared to the normal tissues. In contrast, expressions of BLT1 and BLT2, receptors for leukotriene B4, did not change in the endometriosis. These observations suggest a possible role of LXA4 and the receptor under physiological estrus cycle and pathological condition as endometriosis.

[Long survival with chronic ventricular fibrillation under support of uni-left-ventricular assist system].

Few minutes of suspended malignant ventricular arrhythmia may be permitted for the patient with left ventricular assist system (LVAS). However, longer and continuous ventricular arrhythmia, especially ventricular fibrillation (Vf), may induce the low output of LVAS, which leads circulatory collapse immediately. Our presenting case is a female dilated cardiomyopathy patient who has been supported with LVAS. Four months after the LVAS installation, her electrocardiogram has changed to Vf without any symptoms. Her ventricular function has never recovered, even ventricular tachycardia. She has been a candidate of heart transplantation for more than 19 months with this rare hemodynamic condition (LVAS+Vf), like the Fontan circulation. Her performance status is limited due to deceasing of the LVAS flow, which caused by the change of her position: 2.5-2.9 l/min (lie down) to 2.0 l/min (rise). Her peak VO2/W is 6.9 ml/min/kg measured by the cardio-pulmonary exercise test. However, she has developed her general status by doing rehabilitation program and is able to walk for more than 100-150 meters.

Effects of selective cyclooxygenase inhibitors on ischemia/reperfusion-induced hepatic microcirculatory dysfunction in mice.

We examined the effects of selective cyclooxygenase (COX) inhibition on hepatic warm ischemia/reperfusion (I/R) injury in mice. A selective COX-1 inhibitor, SC-560, selective COX-2 inhibitors, NS-398 and celecoxib, and indomethacin were administered 30 min before ischemia. Four hours after reperfusion, an in vivo microscopic study showed that I/R caused significant accumulation of leukocytes adhering to the hepatic microvessels and nonperfused sinusoids. Levels of plasma alanine transaminase (ALT) and tumor necrosis factor (TNF)-alpha also showed increases. SC-560, NS-398, celecoxib and indomethacin significantly reduced hepatic responses to I/R including microcirculatory dysfunction and release of ALT and TNF-alpha. Moreover, the effects of the thromboxane (TX) A(2) (TXA(2)) synthase inhibitor OKY-046 and the TXA(2) receptor antagonist S-1452 on hepatic responses to I/R exhibited results similar to those obtained with COX inhibitors. These results suggest that COX-1 and COX-2 contribute to I/R-induced hepatic microvascular and hepatocellular injury partly through TNF-alpha production, and that TXs derived from COX are partly responsible for I/R-induced liver injury.

Endogenous prostaglandin I2 regulates the neural emergency system through release of calcitonin gene related peptide.

BACKGROUND: We previously reported that endogenous prostaglandin I(2), generated by a mild irritant, sensitised calcitonin gene related peptide (CGRP) containing sensory nerves and facilitated the release of CGRP and gastric mucosal protection against ethanol. Administration of capsaicin also inhibited ethanol induced gastric mucosal injury through immediate release of CGRP from primary sensory neurones, which is termed the neural emergency system. In the present study, we tested whether endogenous prostaglandin I(2) also modulates the cytoprotective action of capsaicin using prostaglandin I receptor knockout mice (IP(-/-)). METHODS: The stomachs of IP(-/-) or their wild-type counterparts (IP(+/+)), anaesthetised with urethane (1.225 g/kg), were doubly cannulated from the oesophageal and duodenal sides, and the gastric mucosa was perfused (1 ml/min) with physiological saline. Perfusate was changed to 50% ethanol alone, or 50% ethanol containing capsaicin (16 approximately 1600 micro M). The injured area was estimated at the end of each perfusion experiment. In some animals, CGRP-(8-37), a CGRP antagonist (0.3 mg/kg), or indomethacin (1 mg/kg) was intravenously injected before perfusion of 50% ethanol containing capsaicin. RESULTS: Capsaicin inhibited the injured area in a dose dependent manner. Fifty per cent ethanol containing capsaicin (480 micro M) immediately increased intragastric levels of CGRP although 50% ethanol alone did not. The protective action of capsaicin (480 micro M) against ethanol was completely abolished by intravenous injection of CGRP-(8-37). Indomethacin also inhibited the protective action of capsaicin, and this was accompanied by reduced levels of intragastric CGRP. Intragastric levels of prostaglandin E(2) were not increased by capsaicin treatment but those of 6-keto-prostaglandin F(1alpha), a metabolite of prostaglandin I(2), were markedly increased. No protective action of capsaicin was observed in IP(-/-) which lacked the ability to increase intragastric CGRP levels in response to ethanol containing capsaicin. The CGRP content of the stomach from untreated IP(-/-) did not differ from those in IP(+/+). Capsaicin (160 micro M) together with intragastric perfusion of beraprost sodium (PGI(2) analogue, 2.5 micro g/ml) showed enhanced protection against ethanol induced injury. This enhanced protection was completely blocked by intravenous injection of CGRP-(8-37). CONCLUSIONS: The present results suggest that endogenous prostaglandin I(2) enhances the protective action of the capsaicin mediated neural emergency system against ethanol induced gastric mucosal injury through enhancement of CGRP release.

Amelioration of hyperalgesia by kinin receptor antagonists or kininogen deficiency in chronic constriction nerve injury in rats.

OBJECTIVE: The present study was designed to examine the involvement of bradykinin in thermal and mechanical hyperalgesia induced by chronic constriction nerve injury (CCI) using B1 and B2 receptor antagonists and mutant kininogen-deficient rats. METHODS: Sprague-Dawley (SD) rats and Brown Norway (B/N-) rats given CCI treatment on day 0, were used as a model of neuropathic pain. Either a kinin B1 antagonist des-Arg9-[Leu8]-bradykinin or the receptor B2 antagonist HOE-140 was constantly infused into the left jugular vein of SD rats on days 15 to 22 after CCI. Vehicle-treated rats and sham-operated rats without nerve injury were also prepared as controls. In all rats, we observed pain behavior, and measured the latency period of paw withdrawal from the thermal stimuli and, with von Frey filaments, the mechanical pain threshold, before surgery and on days 14 and 22 after CCI. B/N-Katholiek rats, which congenitally lack plasma kininogen and release no kinin, were also tested for hyperalgesic parameters. Expression of kinin receptor mRNA in the dorsal root ganglia was detected by RT-PCR. RESULTS: Most of the rats (88%) showed some pain behavior, which was reduced to 67% by a B1 antagonist and to 57% by a B2 antagonist infused between days 15 to 22. Thermal hyperalgesia was significantly reduced from 7.25 +/- 0.41 sec (mean +/- SEM) to 8.36 +/- 0.41 sec in paw withdrawal latency on day 22 by a B1 antagonist and from 7.24 +/- 0.19 sec to 8.23 +/- 0.21 sec by a B2 antagonist (P < 0.05). Mechanical hyperalgesia was also ameliorated from 0.02 +/- 0.007 g force to 0.16 +/- 0.08 g force in pain threshold by a B1 antagonist and from 0.03 +/- 0.007 g force to 0.10 +/- 0.003 g force on day 22 by a B2 antagonist. Moreover, deficient B/N-Katholiek rats showed a low incidence of thermal and mechanical hyperalgesia on day 14. Expression of both B1 and B2 receptor mRNAs was detected in the lumbar dorsal ganglia ipsilateral to the site of the nerve injury. CONCLUSION: These data suggests that kinin were at least partly involved in yielding nociceptor hypersensitivity up to day 14 after CCI. Bradykinin and its B1 and B2 receptors were involved in the maintenance of hyperalgesia.

Enhanced exudation of fibrinogen into the perivascular space in acute inflammation triggered by neutrophil migration.

OBJECTIVE: The present experiments were performed to ascertain whether or not all plasma components are extravasated when vascular permeability is increased. ANIMALS: Male Sprague-Dawley strain rats (specific pathogen-free) 8 weeks old (for histamine exudation) or 9-10 weeks old (for carrageenin pleurisy) were used. METHODS: Histamine or A-carrageenin was injected into the rat right pleural cavity to induce rat pleurisy. Protein components in the inflammatory exudate and plasma were separated by high performance liquid chromatography. Coagulation time was assessed, and the fibrinogen levels in the pleural exudate were determined by thrombin time. The fibrinogen levels were also visualized by immunoblot analysis. Tumor necrosis factor-alpha (TNF-alpha, 0.4 microg/rat, intrapleurally), anti-rat CD18 monoclonal antibody (anti-CD18 antibody, 1 mg/kg, i. v.) and granulocyte-colony stimulating factor (G-CSF, 100 microg/kg, s.c. twice daily for 4 days) were used. RESULTS: In the histamine-induced extravasation, the level of plasma protein components with large molecules over 900 kD in the exudate was 62% of that in the rat's own plasma. The amount of fibrinogen in the pleural exudate was 1/8 of that in the plasma and was faintly detected in immunoblot analysis, but it was clearly detected after the treatment of rats with TNF-alpha. In rat carrageenin pleurisy, fibrinogen was hardly detected in immunoblot analysis in the exudate collected 0.5 h after carrageenin, when neutrophils did not migrate into the exudate. However, it was clearly present after neutrophil migration started 2 h later The increase in the neutrophil counts in the exudate caused by G-CSF enhanced the fibrinogen level in the exudate, whereas intravenous injection of anti-CD18 antibody suppressed the fibrinogen level in immunoblot analysis. CONCLUSIONS: Venular permeability increase in the rat histamine exudation induced minimal extravasation of plasma proteins with large molecules, such as fibrinogen, while fibrinogen molecule was detected in rat carrageenin-injected pleurisy, when neutrophil diapedesis occurred. Thus, only when neutrophils started to migrate into the perivascular space was fibrinogen clearly detected in the exudate.

Nitric oxide is generated in smooth muscle layer by neurokinin A and counteracts constriction in guinea pig airway.

It has been reported that several bronchoconstrictors generate nitric oxide (NO), counteracting bronchoconstriction, and removal of bronchial epithelia reduces NO production. However, it has not been elucidated whether neurokinin A (NKA), a potent bronchoconstrictor liberated from nerve terminals, generates NO. Specific questions in this study were (1) does NKA also generate NO, (2) does NO counteract NKA-induced bronchoconstriction, and (3) does the NO generation require bronchial epithelial cells? In an in vivo study exogenous as well as endogenous (capsaicin-induced) NKA increased airway opening pressure (P(ao)) and the exhaled NO level, and both were inhibited by an antagonist selective for NK(2) receptor (a receptor for NKA), SR48968. The exhaled NO level became negligible with an inhibitor of NO synthase (NOS) type 1-3 (N(G)-nitro-L-arginine methyl ester, L-NAME) with increased P(ao), but not with a NOS type 2 inhibitor. In an in vitro study, NKA increased the nitrite/nitrate level in superfused fluid of tracheal segments. Removing smooth muscle reduced nitrite/nitrate in the fluid to negligible levels, while the level was unchanged with removal of the epithelia. Pretreatment with l-NAME enhanced the tension of epithelia-removed tracheal segments. These findings indicate that (1) NKA generates NO, (2) NO counteracts NKA-induced bronchoconstriction, and (3) NKA activates NOS in the muscle layer, independently of bronchial epithelia.

FR167653, a cytokine synthesis inhibitor, exhibits anti-inflammatory effects early in rat carrageenin-induced pleurisy but no effect later.

We prepared a pharmacological profile of FR167653 (1-[7- (4-fluorophenyl)-1,2,3,4-tetrahydro-8-(4-pyridyl) pyrazolo[5,1-c][1,2,4]triazin-2-yl]-2-phenylethanedion sulfate monohydrate), a cytokine synthesis inhibitor, on early (5 h after irritation) and late (14-24 h after irritation) phases of rat carrageenin-induced pleurisy and on mediator-induced plasma exudation, in comparison with that of dexamethasone. In the early phase, FR167653 (30 mg/kg) and dexamethasone (0.3 mg/kg) equipotently suppressed plasma exudation and leukocyte infiltration. Furthermore, both agents significantly lowered the prostanoid levels in the exudate. Expression of cyclooxygenase-2 protein on leukocytes in the early phase of inflammation was not affected by dexamethasone, but it was suppressed by FR167653. However, FR167653 did not significantly affect the leukocyte mRNA level of cyclooxygenase-2. Both agents significantly suppressed the levels of both tumor necrosis factor-alpha and interleukin-1beta. FR167653 had a different pharmacological profile from dexamethasone in the late phase of this model in that, unlike dexamethasone, it did not affect cyclooxygenase-2 expression in mesothelial cells, the 6-keto-prostaglandin F1alpha level in the exudate or hyperplasia of mesothelium. Furthermore, unlike dexamethasone, FR167653 did not consistently inhibit mediator-induced plasma exudation. These results suggest that FR167653 or one of its analogs may be new candidates for therapy with a spectrum of activity distinct from that of current anti-inflammatory steroids.

Transient prevention of ethanol-induced gastric lesion by capsaicin due to release of endogenous calcitonin gene-related peptide in rats.

Pre-exposure of the rat gastric mucosa to capsaicin reduced the mucosal lesion by 50% ethanol to 1/4. Treatment with an antagonist of calcitonin gene-related peptide (CGRP), CGRP (8-37), nullified the effect of capsaicin. During constant perfusion of the gastric lumen with physiological saline + pepstatin, the CGRP level was not increased by 50% ethanol, but it showed a peak (802.5 +/- 145.7 pg/2 min) after 1.6 mM capsaicin. Four minutes after capsaicin, the CGRP level was kept at a high level and the gastric lesion was markedly reduced by re-exposure of the mucosa to 50% ethanol. At 20-30 min after capsaicin, the CGRP levels returned to the resting level and the reddened area by 50% ethanol was not reduced. It was concluded that capsaicin transiently prevented the mucosal lesion through CGRP release.

Proinflammatory characteristics of a nonpeptide bradykinin mimic, FR190997, in vivo.

1. Proinflammatory potency of the nonpeptide bradykinin (BK) B(2) receptor agonist FR190997 (8-[2,6-dichloro-3-[N-[(E)-4-(N-methylcarbamoyl)cinnamidoacetyl]-N-methylamino]benzyloxy]-2-methyl-4-(2-pyridylmethoxy)quinoline) was investigated. 2. Intradermal injection of FR190997 (0.03 - 3 nmol site(-1)) into dorsal skin of rats increased vascular permeability in a dose-dependent manner. The effect was less than that of BK, but it was long-acting and was inhibited by treatment with FR173657 (3 mg kg(-1), p.o.). Captopril (10 mg kg(-1), i.p.) did not enhance the plasma extravasation by FR190997 (0.3 nmol site(-1)) in the presence of soybean trypsin inhibitor (SBTI, 30 microg site(-1)). 3. Subcutaneous injection of FR190997 (3 nmol site(-1)) into the hindpaw of mice markedly induced paw swelling. The oedema lasted up to 3 h after the injection. Administration of indomethacin or NS-398 (10 mg kg(-1), i.p.) significantly reduced it at 3 h after the injection. 4. Simultaneous i.p. injection of prostaglandin (PG) E(2) (1 nmol site(-1)) or beraprost sodium (0.5 nmol site(-1)) with FR190997 (5 nmol site(-1)) greatly enhanced frequency of writhing reactions in mice. 5. FR190997 (0.3 - 30 nmol kg(-1), i.v.) showed less increase in airway opening pressure (Pao) in the guinea-pig after i.v. injection. Furthermore, FR190997 (0.03 - 30 nmol) resulted in a very weak contraction of tracheal ring strips and lung parenchymal sections in vitro. 6. In mice sponge implants, topical application of FR190997 increased angiogenesis and granulation with enhanced expressions of basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) mRNAs. 7. These results indicate that FR190997 has proinflammatory long-lasting characteristics and it might be 'a stable tool' for studying the role of BK B(2) receptor in vivo.

Participation of cyclooxygenases in cutaneous thermal nociception under non-inflamed and inflamed conditions.

OBJECTIVE AND DESIGN: Effects of cyclooxygenase inhibitors on noxious thermal stimuli were investigated in non-inflamed and inflamed rats. MATERIALS: Male Sprague-Dawley rats were used in this study. TREATMENT: Cyclooxygenase inhibitors, indomethacin, mofezolac, NS-398, and JTE-522 were administered orally at a dose of 10 mg/kg 1 h prior to and 4 h after the intravenous injection of lipopolysaccharide (1 mg/kg). METHODS: The nociceptive response was evaluated from the escape latency of foot withdrawal to the thermal stimuli with a beam of light. Expression ofcyclooxygenase was examined by reverse transcription-polymerase chain reaction. RESULTS: In normal rat, administration of indomethacin, relatively cyclooxygenase-1-selective inhibitor, mofezolac, or cyclooxygenase-2-selective inhibitors, NS-398 and JTE-522 had no effects on the escape latency against thermal stimuli. Injection of lipopolysaccharide into rat induced the expression of mRNA for cyclooxygenase-2 in the subcutaneous tissue of foot pad. The escape latency at 8 h was significantly shortened by the injection. This hyperalgesia could be reversed by pretreatment of rat with NS-398 or JTE-522, but not with mofezolac. CONCLUSIONS: Cyclooxygenases may have little participation in peripheral skin thermal nociception in non-inflamed condition, although cyclooxygenase-2 could be responsible for the hyperalgesia during inflammation induced by lipopolysaccharide.

Change in tissue kallikrein level in nasal wash after the administration of oxatomide in patients with nasal allergy.

The tissue kallikrein level in the nasal wash was measured before and after 4-week administration of oxatomide (30 mg per day) in 9 patients with perennial allergy. It was found that tissue kallikrein level in the nasal wash obtained following provocation tests significantly decreased from 6.05 +/- 4.43 (10(-10) mol/hour/L) to 1.84 +/- 0.93 (10(-10) mol/hour/L) after the administration of oxatomide. Improvement in subjective symptoms was also observed in all patients after the administration. These results would indicate that kinin in the system is actively involved in the pathogenesis of nasal allergy.