Ketoprofen-induced cyclooxygenase inhibition in renal medulla and platelets of rats treated with caffeine.

It has been suggested that caffeine can augment analgesic activity and aggravate side effects of nonsteroidal anti-inflammatory drugs (NSAIDs). The aim of the present study was to investigate a possible interaction between ketoprofen and caffeine on prostaglandin (PG) biosynthesis and cyclooxygenase (COX) mRNA expression in the rat renal medulla ex vivo. Treatment of rats with ketoprofen (60 min before) resulted in a dose-dependent (estimated ID(50) 0.3 mg/kg p.o.) reduction of PGE(2) biosynthesis in renal medulla ex vivo. Ketoprofen (0.3 mg/kg)-induced inhibition of PGE(2) biosynthesis was stable between 30 and 180 min and still detectable 300 min after drug administration. Caffeine (10 mg/kg) did not cause a detectable effect on its own, nor did it significantly affect ketoprofen-induced inhibition of renal medullary PGE(2) biosynthesis. Similar results were obtained with repeated daily drug administration for 1 week: there was no significant effect of caffeine on ketoprofen-induced inhibition of renal medullary PGE(2) biosynthesis. The absence of significant caffeine effects on ketoprofen-induced inhibition of renal medullary PGE(2) biosynthesis was paralleled by experiments showing no significant effect of caffeine on ketoprofen-induced inhibition of platelet thromboxane (TX)B(2) biosynthesis. Additional experiments showed increased COX-2 mRNA expression in the renal medulla 60 min after ketoprofen administration, that was not significantly influenced by concomitant caffeine treatment. Treatment of rats with ketoprofen for 1 week had no significant effects on COX-2 mRNA expression. The present results show that ketoprofen caused inhibition of PGE(2) biosynthesis in the rat renal medulla ex vivo with a potency similar to that reported for in vivo models suggesting that the ex vivo approach is a valid model to test a possible interference of caffeine with ketoprofen-induced COX inhibition. The absence of detectable effects of caffeine on time course or magnitude of ketoprofen-induced suppression of PGE(2) biosynthesis in this model indicates, therefore, that possible adverse actions of co-administered caffeine on renal function are not related to interference with renal COX inhibition.

HU-210 shows higher efficacy and potency than morphine after intrathecal administration in the mouse formalin test.

The discovery of endocannabinoids opens up new perspectives in experimental pain research. Here we present data for the excellent antinociceptive properties of the synthetic cannabinoid, R(-)-7-hydroxy-delta-6-tetra-hydrocannabinol-dimethylheptyl (HU-210), after intrathecal and oral administration in mice. It is known that cannabinoids depress motor activity. Therefore, these compounds are suspected of influencing antinociceptive tests. Our behavioural tests (RotaRod, tail flick) clearly show that HU-210 affects nociceptive behaviour even at dosages which do not yet influence motor activity. Moreover, spinal microdialysis (5 microl/min) in the dorsal horn of freely moving mice showed an enhancement of prostaglandin production during the formalin test. HU-210 applied via artificial cerebral spinal fluid during microdialysis perfusion increases prostaglandin concentrations under both baseline and formalin test conditions. Indomethacin reduces the HU-210 effect on pronociceptive prostaglandin production but does not reinforce the antinociceptive properties of HU-210. Thus, HU-210 shows antinociceptive properties that are independent of its influence on the prostaglandin pathway.

Expression of cyclooxygenase-1 and -2 in normal and glaucomatous human eyes.

PURPOSE: Primary open-angle glaucoma (POAG) is the predominant form of chronic glaucoma, but the underlying pathologic mechanisms are largely unknown. Because prostaglandins (PGs) have been introduced into POAG treatment with remarkable success, this study was undertaken to investigate whether a change in the expression of the PG-synthesizing enzymes cyclooxygenase (COX)-1 and -2 might be involved in the pathogenesis of POAG. METHODS: Expression of COX-1 and -2 was assessed by confocal laser microscopy, immunohistochemistry, Western blot analysis, and real-time RT-PCR in human eyes with different forms of glaucoma (primary open-angle, angle-closure, congenital juvenile, and steroid-induced), as well as in age-matched control eyes. Additionally, PGE2 was measured in aqueous humor by means of an enzyme-linked immunoassay as a product of COX activity. RESULTS: In normal eyes, ocular COX-1 and -2 expression were largely confined to the nonpigmented secretory epithelium of the ciliary body. By immunohistochemistry and real-time RT-PCR, COX-2 expression was completely lost in the nonpigmented secretory epithelium of the ciliary body of eyes with end-stage POAG, whereas COX-1 expression was unchanged. By immunohistochemistry, in the ciliary bodies of eyes in five patients with diagnosis of early POAG, eyes in two had complete loss of COX-2 expression and in three showed only a few remaining scattered COX-2-expressing cells. COX-2 expression in the ciliary body was also lost in patients with steroid-induced glaucoma and was reduced in patients receiving topical steroid treatment. Eyes of patients with either congenital juvenile or angle-closure glaucoma showed COX-2 expression indistinguishable from control eyes. Aqueous humor of eyes with POAG contained significantly less PGE2 than control eyes. CONCLUSIONS: Both cyclooxygenase isoforms are constitutively expressed in the normal human eye. Specific loss of COX-2 expression in the nonpigmented secretory epithelium of the ciliary body appears to be linked to the occurrence of POAG and steroid-induced glaucoma.

Role of nitric oxide in zymosan induced paw inflammation and thermal hyperalgesia.

OBJECTIVE: To assess the involvement of spinal inducible nitric oxide synthase (iNOS) in inflammation and nociception. MATERIALS AND METHODS: The time course of iNOS mRNA expression in rat spinal cord and inflamed paw was assessed by means of quantitative real time RT-PCR. In addition, the effects of the iNOS inhibitor L-NIL on inflammatory paw edema and thermal hyperalgesia were studied in comparison to those of the NO-donor RE-2047. L-NIL (3, 9, 27 and 81 mg/kg) and RE-2047 (3, 9 and 27 mg/kg) or vehicle were administered orally 15 min prior to the intraplantar injection of 0.625 mg zymosan. RESULTS: Following zymosan injection, mRNA expression of iNOS increased in the inflamed paw and spinal cord with a maximum at 2.5 and 4 h, respectively. In the spinal cord iNOS mRNA started to decline at 10 h whereas it remained at maximum in the inflamed paw up to the end of the observation period of 24 h. As expected, RE-2047 had significant pronociceptive and proinflammatory effects. L-NIL significantly reduced paw inflammation at 27 and 81 mg/kg but failed to reduce hyperalgesia at the doses tested. CONCLUSIONS: The results show that iNOS is upregulated in the inflamed tissue and spinal cord with a similar time course. The effects obtained with L-NIL suggest that iNOS differently contributes to the inflammatory and nociceptive response induced by zymosan.

Modulation of synaptic transmission by nociceptin/orphanin FQ and nocistatin in the spinal cord dorsal horn of mutant mice lacking the nociceptin/orphanin FQ receptor.

Nociceptin/orphanin FQ (N/OFQ) and nocistatin (NST) are two neuropeptides derived from the same precursor protein that exhibit opposing effects on spinal neurotransmission and nociception. Here, we have used whole-cell, patch-clamp recordings from visually identified neurons in spinal cord dorsal horn slices of genetically modified mice to investigate the role of the N/OFQ receptor (N/OFQ-R) in the modulatory action of both peptides on excitatory glutamatergic and inhibitory glycinergic and gamma-aminobutyric acid (GABA)-ergic synaptic transmission. In wild-type mice, N/OFQ selectively suppressed excitatory transmission in a concentration-dependent manner but left inhibitory synaptic transmission unaffected. In contrast, NST reduced only inhibitory but not alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptor-mediated excitatory synaptic transmission. N/OFQ-mediated inhibition of excitatory transmission was completely absent in N/OFQ-R receptor-deficient (N/OFQ-R(-/-)) mice and significantly reduced in heterozygous (N/OFQ-R(+/-)) mice, whereas the action of NST on inhibitory neurotransmission was completely retained. To test for the relevance of these results for spinal nociception, we investigated the effects of intrathecally injected N/OFQ in the mouse formalin test, an animal model of tonic pain. N/OFQ (3 nmol/mouse) induced significant antinociception in wild-type mice, but had no antinociceptive effects in N/OFQ-R(-/-) mice. These results indicate that the inhibitory action of N/OFQ on excitatory glutamatergic synaptic transmission and its spinal antinociceptive action are mediated via the N/OFQ receptor, whereas the action of NST is independent of this receptor.

Inhibition of NF-kappaB and AP-1 activation by R- and S-flurbiprofen.

R-flurbiprofen is considered the 'inactive' isomer of the nonsteroidal anti-inflammatory drug (NSAID), flurbiprofen, because it does not inhibit cyclooxygenase (COX) activity. However, previous studies have revealed that it has antinociceptive and antitum or effects not due to epimerization to the cyclooxygenase-inhibiting S-isomer. Here, we show that R-flurbiprofen has additional anti-inflammatory activity comparable with that of dexamethasone in the zymosan-induced paw inflammation model in rats. Different criteria suggest that the observed effects are mediated at least in part through inhibition of NF-kB activation: R-flurbiprofen inhibited i) LPS-induced NF-kB DNA binding activity in RAW 264.7 macrophages, ii) translocation of the p65 subunit of NF-kB into the nucleus of these cells, and iii) zymosan-induced NF-kB-dependent gene transcription in the inflamed paw and spinal cord of rats. S-flurbiprofen produced similar effects but was less potent. In addition, R-flurbiprofen inhibited DNA binding activity of AP-1, another key regulatory transcription factor in inflammatory processes. Because R-flurbiprofen does not cause gastrointestinal mucosal damage or other side effects associated with long-term NSAID or glucocorticoid use, it might be a useful drug in inflammatory or other diseases in which increased or constitutive NF-kB and AP-1 activation are involved in the pathophysiological processes.

Suppressed injury-induced rise in spinal prostaglandin E2 production and reduced early thermal hyperalgesia in iNOS-deficient mice.

It is widely accepted that peripheral injury increases spinal inducible cyclooxygenase (COX-2) expression and prostaglandin E(2) (PGE(2)) formation as key mediators of nociceptive sensitization. Here, we used inducible nitric oxide synthase (iNOS) gene-deficient (iNOS-/-) mice to determine the contribution of iNOS-derived nitric oxide (NO) to this process. iNOS-/- mice exhibited reduced thermal hyperalgesia after zymosan injection. Spinal NO and PGE(2) formation both remained at baseline levels, in contrast to wild-type (wt) mice. In wt mice reduced hyperalgesia similar to that seen in iNOS-/- mice was induced by local spinal, but not by systemic treatment with the iNOS inhibitor l-NIL, suggesting that the reduced heat sensitization in iNOS-/- mice was attributable to the lack of spinal rather than peripheral iNOS. Two additional observations indicate that the antinociceptive effects of iNOS inhibition are dependent on a loss of stimulation of PG synthesis. First, intrathecal injection of the COX inhibitor indomethacin, which exerted pronounced antinociceptive effects in wt mice, was completely ineffective in iNOS-/- mice. Second, treatment with the NO donor RE-2047 not only completely restored spinal PG production and thermal sensitization in iNOS-/- mice but also its sensitivity to indomethacin. In both types of mice induction of thermal hyperalgesia was accompanied by similar increases in COX-1 and COX-2 mRNA expression. The stimulation of PG production by NO therefore involves an increase in enzymatic activity, rather than an alteration of COX gene expression. These results indicate that NO derived from spinal iNOS acts as a fast inductor of spinal thermal hyperalgesia.

Selective suppression of inhibitory synaptic transmission by nocistatin in the rat spinal cord dorsal horn.

Nociceptin/orphanin FQ (N/OFQ) and nocistatin (NST) are two recently identified neuropeptides with opposing effects on several CNS functions, including spinal nociception. The cellular mechanisms that underlie this antagonism are not known. Here, we have investigated the effects of both peptides on synaptic transmission mediated by the three fast neurotransmitters l-glutamate, glycine, and GABA in the superficial layers of the rat spinal cord horn, which constitute the first important site of integration of nociceptive information in the pain pathway. NST selectively reduced transmitter release from inhibitory interneurons via a presynaptic Bordetella pertussis toxin-sensitive mechanism but left excitatory glutamatergic transmission unaffected. In contrast, N/OFQ only inhibited excitatory transmission. In the rat formalin test, an animal model of tonic pain in which N/OFQ exerts antinociceptive activity, NST induced profound hyperalgesia after intrathecal application. Similar to glycine and GABA(A) receptor antagonists, NST had no significant effects in the rat tail-flick test, a model of acute thermal pain. Our results provide a cellular basis for the antagonism of N/OFQ and NST and suggest the existence of a so far unidentified membrane receptor for NST. In addition, they support a role of NST as an endogenous inhibitor of glycinergic and GABAergic neurotransmission in the sensory part of the spinal cord and as a mediator of spinal hyperalgesia.

Effects of selective and unselective cyclooxygenase inhibitors on prostanoid release from various rat organs.

It has been assumed that cyclooxygenase-2 (COX-2) is solely responsible for inflammatory processes. Recently, this view has been challenged because COX-2-selective agents caused a delay of gastric ulcer healing and exacerbation of inflammation in rats. To further characterize organ-specific toxic effects of selective and nonselective COX inhibitors, we assessed the eicosanoid release from different rat organs ex vivo after oral administration of the COX-2-selective inhibitor NS-398 and the unselective COX inhibitors diclofenac, meloxicam, and ketorolac. Prostanoid and leukotriene release from tissue fragments of the stomach, kidney, lung, and brain were determined after ex vivo incubation of tissue fragments in Tyrode's solution for 10 min at 37 degrees C. Ketorolac (0.1, 0.3, and 0.9 mg/kg) inhibited prostanoid release from all organs most potently and led to a significant increase of leukotriene release from the lung. Effects of diclofenac and meloxicam (1, 3, and 9 mg/kg each) were similar for all organs tested. At 9 mg/kg, 6keto-prostaglandin F (PGF)(1alpha) release from gastric mucosa was reduced by 79.1 +/- 11.4 and 87.6 +/- 7.7% and PGE(2) release from rat kidney was inhibited by 60.4 +/- 6.8 and 78.6 +/- 16.6% by diclofenac and meloxicam, respectively. NS-398 did not reduce prostanoid release from the lung. Consistent with the reported constitutive expression of COX-2, prostanoid release from kidney and brain was reduced by 20 to 30%. The release of 6keto-PGF(1alpha) from gastric mucosa was reduced by 34.7 +/- 22.2% at 3 mg/kg and by 86.9 +/- 12.7% at 9 mg/kg. At these doses, NS-398 has been previously shown to be COX-2 selective. Because PGF(1alpha) is the stable breakdown product of PGI(2), these results suggest that COX-2 contributes to PGI(2) synthesis in the rat stomach.

Muscle damping measured with a modified pendulum test in patients with fibromyalgia, lumbago, and cervical syndrome.

STUDY DESIGN: Muscle tension with tenderness may be localized or generalized as in fibromyalgia. Wartenberg's pendulum test might be appropriate for quantitating muscle damping, at least in generalized cases. OBJECTIVE: Damping values provide a quantitative measure of muscle tension and of the response to various treatments. SUMMARY OF THE BACKGROUND DATA: According to recent anatomic and experimental works, intrafusal muscle fibers are double-innervated by gamma motoneurons and sympathetic fibers. With electromyograph recording, the activity of extrafusal fibers and gamma motoneurons (reflexes) can be assessed and separated from the action of the sympathetic system. METHODS: An electrogoniometer registers the movements of the freely swinging leg. On the oscilloscope, the patient's nodular curve is compared with an ideal calculated dampened curve to find the damping value. Electromyograph surface electrodes from the knee extensors and flexors detect the activity of extrafusal fibers and the occurrence of reflexes. RESULTS: In longstanding severe fibromyalgia, damping values are almost always elevated, at least in one leg. Half or more of patients with chronic lumbago and cervical syndrome present with increased damping. The surface electromyograph remains silent (in contrast to spastic patients). CONCLUSION: The findings support the hypothesis that muscle tension in rheumatic patients results from overactivity of the sympathetic system (or part of it). Even in clinically localized pain syndromes, muscle damping is often increased in the legs. The test is valuable for quantitating muscle tension and the effectiveness of therapeutic methods.

[Complex treatment concept of psoriasis vulgaris in childhood with integrated high altitude-climate therapy]. / Komplexes Behandlungskonzept der Psoriasis vulgaris im Kindesalter bei integrierter Hochgebirgs-Klimatherapie.

A sample of 102 inpatient children with psoriasis demonstrated differences in appearance and treatment to the psoriasis of adults. The complex therapy concept is based on 5 elements with dermatologic, high-altitude climatic and psychological treatment. Important additional factors are pre-school and school activities and vocational assistance. Of utmost importance is an early step-by-step education of the parents and of the psoriasis child about the disease. Medical treatment is effectively completed and optimised by an appropriate life style and multiple prophylactic activities in the premedical and environmental fields of the diseased. Dermatologists and pediatrists should aim at on-target and well-organised medical guidance of the young psoriatics.

[Complex high altitude climate therapy for children and adolescents with neurodermitis constitutionalis atopica]. / Komplexe Hochgebirgs-Klima-Therapie für Kinder und Jugendliche mit Neurodermitis constitutionalis atopica.

Neurodermitis constitutionalis atopica is a multifactor conditioned disease with a very wide range of aetiopathogenetic factors. A standard therapy does not exist. For children and young adults we have come to terms with a treatment concept, that consists in essence of 5 elements. Our basis is the dermatological and allergical treatment plan. We added and integrated factors of high mountain climate, psychotherapy as well as teaching- and children-garden-activities. This complex therapy is condition for optimal results in treating children and young adults.

[Inhalation mite provocation in atopic patients in relation to high altitude conditions]. / Inhalative Milbenprovokation bei Atopikern unter Hochgebirgsbedingungen.

The clinical diagnosis of allergy of the respiratory system caused by flour or dust mites--i.e. perennial bronchial asthma and/or allergic rhinitis--hat to be proved by the case history, prick test, RAST, as well as provocative inhalation, before any hyposensitization measures are taken. The mountain climate (above 1500 m) is especially appropriated for these procedures since mites cannot live here. With regard to the pulmonary function and the correlation to RAST, we evaluated 83 specific bronchial and nasal provocative inhalation tests with dust or flour mites performed on patients suffering from atopic dermatitis and allergies of the respiratory system.

[Diagnosis and hyposensitization treatment of patients with house dust mite allergies in high mountain areas]. / Diagnostik und Hyposensibilisierungsbehandlung von Hausstaubmilben-Allergikern unter Hochgebirgsbedingungen.

The fact that house dust mite can't exist in the high mountains above an altitude of 1500 m permits diagnostics bearing only low risks (to prove actual hyposensitivity with the help of provocation tests) and also low risk therapy (hyposensitization therapy). Allergenic extracts of freeze-dried mites (Pharmalgen) have the advantage of being immediately and for different patients available.