ovalbumin and Pain

Sensory nerve fibers innervating the ocular anterior surface detect external stimuli producing innocuous and painful sensations. Protons are among the first mediators released by damaged cells during inflammation, tissue injury, or other chronic ophthalmic conditions. We studied whether acid-sensing ion channels (ASICs) are expressed in corneal sensory neurons and their roles in the response to moderate acidifications of the ocular surface and in pathologies producing ocular surface inflammation. Moderate acidic pH (6.6) activated ASIC-like currents in corneal sensory neurons, which were blocked by ASIC1- or ASIC3-specific toxins. Acidic pH depolarizes corneal sensory neurons to fire action potentials, an effect blocked by the ASIC3 inhibitor APETx2. 2-Guanidino-4-methylquinazoline, an ASIC3 agonist, activated a population of corneal polymodal sensory nerve fibers and significantly increased the blinking and tearing rate. The nocifensive behaviors produced by application of either a moderate acidic stimulus or ophthalmic drugs formulated in acidic solution were abolished by ASIC blockers. In a model of allergic keratoconjunctivitis, nocifensive behavior was greatly reduced by ASIC3 blockade, presumably by reducing nociceptor sensitization during the inflammatory process. Our results show that, in addition to the established role of TRPV1, ASICs play a significant role in the detection of acidic insults at the ocular surface. The identification of ASICs in corneal neurons and their alterations during different diseases is critical for the understanding of sensory ocular pathophysiology. They are likely to mediate some of the discomfort sensations accompanying several ophthalmic formulations and may represent novel targets for the development of new therapeutics for ocular pathologies.

Topics: Acid Sensing Ion Channel Blockers; Acid Sensing Ion Channels; Acids; Action Potentials; Amiloride; Animals; Blinking; Cnidarian Venoms; Cornea; Disease Models, Animal; Dry Eye Syndromes; Eye; Guanidines; Guinea Pigs; Hydrogen-Ion Concentration; Male; Nerve Fibers; Ocular Motility Disorders; Ovalbumin; Pain; Patch-Clamp Techniques; Quinazolines; Rats; Rats, Sprague-Dawley; RNA, Messenger; RNA, Small Interfering; Sensory Receptor Cells; Statistics, Nonparametric

Telfairia occidentalis (Cucurbitaceae) is a tropical vine grown in West Africa as a leaf vegetable and for its edible seeds. The plant is noted to have healing properties. It is used as a blood tonic to revive weak/ill individuals and its use by sickle cell patients has been documented. In this study, the antinociceptive activity of the hydroethanolic leaf extract of Telfairia occidentalis (TO) was evaluated using the acetic acid-induced writhing, formalin, tail clip, and hot plate tests in mice. The carrageenan- and egg albumin-induced rat paw edema tests were used to evaluate the anti-inflammatory action. The extract (50-400 mg/kg, p.o.) produced significant (P<.05) dose-dependent inhibition of pain response elicited by acetic acid and formalin while also increasing the nociceptive reaction latency in the tail clip and hot plate tests. In respect of anti-inflammatory activity, the extract elicited significant (P<.05) time and dose-dependent inhibition of edema development in the carrageenan and egg albumin tests. Peak effects of TO in the models were generally comparable with the effects of the standard drugs (acetylsalicylic acid, morphine, indomethacin, and chlorpheniramine) used. Phytochemical screening of the extract revealed the presence of tannins, saponins, phlobatannins, and anthraquinones. The extract did not produce any mortality and visible signs of delayed toxicity when administered orally up to 2000 mg/kg. The LD50 (i.p.) was estimated to be 4073.80 mg/kg. The results obtained in this study suggest that TO possesses antinociceptive and anti-inflammatory activities possibly mediated through peripheral and central mechanisms involving inhibition of release and/or actions of vasoactive substances and prostaglandins.

Topics: Acetic Acid; Analgesics; Animals; Anti-Inflammatory Agents; Carrageenan; Cucurbitaceae; Edema; Female; Formaldehyde; Hot Temperature; Male; Mice; Ovalbumin; Pain; Pain Measurement; Phytotherapy; Plant Extracts; Plant Leaves

Cynoglossum lanceolatum Forsk. (Boraginaceae) has been used in folk medicine in china to treat acute nephritis, periodontitis, acute submandibular lymphadenitis, snake bite, etc. However, there have been no scientific reports in the modern literature on the diuretic, anti-inflammatory and analgesic effects of this plant. The objective of this study is to evaluate the above activities of the Cynoglossum lanceolatum extract (CLE) in animals.. The diuretic effect of CLE was assessed in rats and rabbits. The anti-inflammatory activity was evaluated using fresh egg white-induced paw edema in rats, carrageenan-elicited paw edema in adrenalectomized rats, and dimethylbenzene-induced inflammation in mice. The analgesic action was estimated in mice using the acetic acid-induced writhing test and the hot-plate test. In addition, the acute oral toxicity of CLE was studied in mice.. CLE strikingly and dose-dependently increased urine output of rats and rabbits, suppressed fresh egg white-induced paw edema in rats and carrageenan-elicited paw edema in adrenalectomized rats, reduced dimethylbenzene-induced ear edema in mice, inhibited the writhing response in mice, but did not increased reaction time of mice in the hot-plate test. No death of mice was observed when orally administered CLE up to 12g/kg.. These findings propose that CLE has evident diuretic, anti-inflammatory, and non-central analgesic activities. Furthermore the anti-inflammatory action does not rely on endogenetic glucocorticoids regulated by hypothalamo-pituitary-adrenal axis. On the other hand, CLE also shows a favorable safety.

Topics: Acetic Acid; Analgesics; Animals; Anti-Inflammatory Agents; Boraginaceae; Carrageenan; Disease Models, Animal; Diuretics; Drugs, Chinese Herbal; Ethanol; Female; Inflammation; Male; Mice; Ovalbumin; Pain; Phytotherapy; Plant Roots; Rabbits; Rats; Rats, Sprague-Dawley; Sodium Chloride; Solvents; Urination; Xylenes

Violacein was isolated from Chromobacterium violaceum, a soil Gram negative bacterium collected from the forest water body soil sample of Kolli Hills; Tamil Nadu, India. In the present study the immunomodulatory, analgesic and antipyretic activities of violacein were investigated in wistar rats and mice. Analgesic effect was evaluated by acetic acid- induced writhing, formalin induced paw licking and hotplate tests. Immunomodulatory effect was investigated by using ovalbumin- induced active paw anaphylaxis and sheep red blood cells (SRBC)-induced DTH tests. Antipyretic activity was evaluated by yeast- induced hyperpyrexia in rats. The anti- oedema effect was compared with indomethacin. Violacein inhibited 42.9% of ovalbumin- induced edema. Further we found that violacein (40mg/kg b.w.) reduced the edema induced by sheep red blood cells. Violacein also produced significant (p<0.05) analgesic activity in acetic acid induced writhing response, formalin induced paw licking response and hot plate analysis. Treatment with violacein showed a significant (p<0.05) dose-dependent reduction in pyrexia in rats. The results suggest that violacein possesses potent immunomodulatory, analgesic and antipyretic activities.

Topics: Acetic Acid; Analgesics; Anaphylaxis; Animals; Behavior, Animal; Chromobacterium; Dose-Response Relationship, Drug; Edema; Erythrocytes; Female; Fever; Formaldehyde; Hot Temperature; Hypersensitivity; Hypersensitivity, Delayed; Immunologic Factors; India; Indoles; Indomethacin; Male; Mice; Ovalbumin; Pain; Rats; Rats, Wistar; Sheep; Yeasts

The root of Paeonia lactiflora PALL (PL, Family Paeoniaceae) has been used frequently as an antipyretic and anti-inflammatory agent in traditional medicines of Korea, China and Japan. To evaluate antiallergic effect of PL, we isolated its main constituents, paeoniflorin and paeonol, and evaluated in vivo their inhibitory effects against passive cutaenous anaphylaxis (PCA) reaction induced by IgE-antigen complex and scratching behaviors induced by compound 48/80. PL, paeoniflorin and paeonol potently inhibited PCA reaction and scratching behaviors in mice. Paeoniflorin exhibited the most potent inhibition against scratching behaviors and the acetic acid-induced writhing syndrome in mice. Paeonol most potently inhibited PCA reaction and mast cells degranulation. These findings suggest that PL can improve IgE-induced anaphylaxis and scratching behaviors, and may be due to the effect of its constituents, paeoniflorin and paeonol.

Topics: Acetic Acid; Acetophenones; Analgesics; Animals; Anti-Allergic Agents; Antipruritics; Asthma; Behavior, Animal; Benzoates; Bridged-Ring Compounds; Cell Degranulation; Disease Models, Animal; Dose-Response Relationship, Drug; Glucosides; Male; Mast Cells; Mice; Mice, Inbred BALB C; Mice, Inbred ICR; Monoterpenes; Ovalbumin; p-Methoxy-N-methylphenethylamine; Paeonia; Pain; Pain Measurement; Passive Cutaneous Anaphylaxis; Plant Roots; Pruritus; Rats; Rats, Sprague-Dawley

There is pre-clinical evidence that therapies targeting IL-18 might be beneficial in controlling arthropathies, which are accompanied by hypernociception (nociceptor sensitization). In the present study, we addressed the hypernociceptive role of IL-18 in a model of antigen-induced inflammation in mice and its mechanisms. In naïve mice, the intraplantar injection of IL-18 induced dose- and time-dependent mechanical hypernociception, which was inhibited in IFN-gamma deficient (-/-) mice, and by the pre-treatment with bosentan (dual endothelin [ET] receptor antagonist), BQ123 (ET(A) receptor antagonist) or indomethacin (cyclooxygenase inhibitor). IL-18 hypernociception was unaffected in TNFR1(-/-) mice or by the pre-treatment with sIL-15Ralpha (soluble form of IL-15 receptor), BQ788 (ET(B) receptor antagonist) or guanethidine (sympathetic blocker). The ovalbumin (OVA) challenge-induced mechanical hypernociception in immunized mice was inhibited by the pre-treatment with anti-IL-18 antibody or in IL-18(-/-) mice. Furthermore, IL-18 induced significant IFN-gamma production in the paw skin of naïve mice. The OVA challenge-induced IFN-gamma and ET-1 productions were inhibited in IL-18(-/-) immunized mice, as well as ET-1 production in IFN-gamma(-/-) immunized mice. In addition, significant PGE2 production was detected after IL-18 or ET-1 (via ET(A) receptors) injection in naïve mice. Taken together with previous data, these results suggest that IL-18 plays a significant role in antigen-induced inflammatory hypernociception via the production of IFN-gamma, ET-1 and PGE2. Thus, IL-18 and IL-18-downstream mediators demonstrated herein might constitute targets to inhibit antigen-induced inflammatory pain.

Topics: Animals; Antigens; Dinoprostone; Dose-Response Relationship, Drug; Interferon-gamma; Interleukin-18; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Knockout; Ovalbumin; Pain; Pain Threshold; Prostaglandin-Endoperoxide Synthases; Receptor, Endothelin A; Receptors, Tumor Necrosis Factor, Type I; Signal Transduction; Stress, Mechanical; Time Factors

In this study, we tested the potential use of a lectin from Lonchocarpus sericeus seeds (LSL), to control neutrophil migration and inflammatory hypernociception (decrease of nociceptive threshold). Pretreatment of the animals intravenously (15 min before) with LSL inhibited neutrophil migration to the peritoneal cavity in a dose-dependent fashion confirmed by an inhibition of rolling and adhesion of leukocytes by intravital microscopy. We also tested the ability of the pretreatment with LSL to inhibit neutrophil migration on immunised mice, and it was observed that a strong inhibition of neutrophil migration induced by ovoalbumin in immunized mice. Another set of experiments showed that pretreatment of the animals with LSL, inhibited the mechanical hypernociception in mice induced by the i.pl. injection of OVA in immunized mice and of carrageenan in naïve mice, but not that induced by prostaglandin E(2) (PGE(2)) or formalin. This anti-nociceptive effect correlated with an effective blockade of neutrophil influx, as assessed by the hind paw tissue myeloperoxidase levels. In addition, we measured cytokines (TNF-alpha and IL-1beta) and chemokines (MIP-1alpha [CCL3] and KC [CXCL1]) from the peritoneal exudates and i.pl. tissue. Animals treated with LSL showed inhibition of cytokines and chemokines release in a dose-dependent manner. In conclusion, we demonstrated that the inhibitory effects of LSL on neutrophil migration and mechanical inflammatory hypernocicepetion are associated with the inhibition of the production of cytokines and chemokines.

Topics: Analgesics; Animals; Anti-Inflammatory Agents; Carrageenan; Cell Adhesion; Cell Movement; Cytokines; Dinoprostone; Fabaceae; Formaldehyde; Immunoglobulin G; Male; Mice; Mice, Inbred BALB C; Neutrophils; Ovalbumin; Pain; Peroxidase; Plant Lectins

In an attempt to scientifically evaluate some of the anecdotal, folkloric, ethnomedical uses of Rhus chirindensis Baker F. ('red currant'), the present study was undertaken to investigate the analgesic, anti-inflammatory and hypoglycaemic effects of the plant's stem-bark aqueous extract (RCE) in mice and rats. The analgesic effect of RCE was evaluated by 'hot-plate' and 'acetic acid' analgesic test methods in mice; while its anti-inflammatory and hypoglycaemic effects were investigated in rats, using fresh egg albumin-induced pedal oedema, and streptozotocin (STZ)-induced diabetes mellitus animal models. Morphine (MPN, 10 mg/kg), diclofenac (DIC, 100 mg/kg) and chlorpropamide (250 mg/kg) were used as reference drugs for comparison. RCE (50-800 mg/kg i.p.) produced dose-dependent, significant (P<0.05-0.001) analgesic effects against thermally- and chemically-induced nociceptive pain in mice. The plant's extract (RCE, 50-800 mg/kg p.o.) also significantly (P<0.05-0.001) inhibited fresh egg albumin-induced acute inflammation, and caused dose-related, significant (P<0.05-0.001) hypoglycaemia in normal (normoglycaemic) and diabetic (hyperglycaemic) rats. The flavonoids, triterpenoids and other chemical compounds present in RCE are speculated to account for the observed pharmacological effects of the plant's extract in the experimental animal paradigms used. The findings of this experimental animal study indicate that Rhus chirindensis stem-bark aqueous extract possesses analgesic, anti-inflammatory and hypoglycaemic properties; and thus lend pharmacological credence to the anecdotal, folkloric, ethnomedical uses of the plant in the treatment and/or management of painful, arthritic, inflammatory conditions, as well as in the management and/or control of type 2 diabetes mellitus in some rural communities of South Africa.

Topics: Analgesics; Animals; Anti-Inflammatory Agents; Blood Glucose; Diabetes Mellitus, Experimental; Dose-Response Relationship, Drug; Female; Hindlimb; Hot Temperature; Hypoglycemic Agents; Inflammation; Injections, Intraperitoneal; Male; Mice; Mice, Inbred BALB C; Ovalbumin; Pain; Plant Bark; Plant Extracts; Plant Stems; Rats; Rats, Wistar; Rhus; Water

The inhibition of prostaglandin (PG) synthesis is at the center of current anti-inflammatory therapies. Because cyclooxygenase-2 (COX-2) inhibitors and nonsteroidal anti-inflammatory drugs (NSAIDs) inhibit the formation of multiple PGs, there is currently a strong focus on characterizing the role of the different PGs in the inflammation process and development of arthritis. Evidence to date suggests that both PGE(2) and PGI(2) act as mediators of pain and inflammation. Most of the data indicating a role for PGI(2) in this context have been generated in animal models of acute pain. Herein, we describe the role of PGI(2) in models of osteoarthritis (OA) and rheumatoid arthritis using a highly selective PGI(2) receptor (IP, Ptgir) antagonist and IP receptor-deficient mice. In the rat OA model using monoiodoacetate injection into the knee joint, the IP antagonist reduced pain with an efficacy approaching that of the NSAID diclofenac. In a chronic model of inflammatory arthritis, collagen-antibody induced arthritis model in mice, IP receptor-deficient mice displayed a 91% reduction in arthritis score. Interestingly, pretreatment with the IP [N-[4-(imidazolidin-2-ylideneamino)-benzyl]-4-methoxy-benzamide] antagonist in this model also caused a significant reduction of the symptoms, whereas administration of the compound after the initiation of arthritis had no detectable effect. Our data indicate that, in addition to its role in acute inflammation, PGI(2) is involved in the development of chronic inflammation. The results also suggest that the inhibition of PGI(2) synthesis by NSAIDs and COX-2 inhibitors, in addition to that of PGE(2), contributes to their efficacy in treating the signs of arthritis.

Topics: Animals; Arthritis, Experimental; Carrageenan; Chromatography, High Pressure Liquid; Chronic Disease; Collagen; Cyclooxygenase 2 Inhibitors; Edema; Epoprostenol; Hot Temperature; Hyperalgesia; Inflammation; Iodoacetates; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Osteoarthritis; Ovalbumin; Pain; Prostaglandins I; Rats; Rats, Sprague-Dawley; Receptors, Epoprostenol

In many parts of Africa, the leaf, stem-bark, and roots of Psidium guajava Linn. (Family: Myrtaceae) are used traditionally for the management, control, and/or treatment of an array of human disorders. In an effort to scientifically appraise some of the ethnomedical properties of P. guajava leaf, and probe its efficacy and safety, the present study was undertaken to examine the antiinflammatory and analgesic properties of the plant's leaf aqueous extract in some experimental animal paradigms. The antiinflammatory property of the aqueous leaf extract was investigated in rats, using fresh egg albumin-induced pedal (paw) edema, while the analgesic effect of the plant extract was evaluated by the "hot-plate" and "acetic acid" test models of pain in mice. Diclofenac (100 mg/kg, i.p.) and morphine (10 mg/kg, i.p.) were used respectively as standard, reference antiinflammatory and analgesic agents for comparison. P. guajava leaf aqueous extract (PGE, 50-800 mg/kg, i.p.) produced dose-dependent and significant (p < 0.05-0.001) inhibition of fresh egg albumin-induced acute inflammation (edema) in rats. The plant extract (PGE, 50-800 mg/kg, i.p.) also produced dose-dependent and significant (p < 0.05-0.001) analgesic effects against thermally and chemically induced nociceptive pain in mice. The numerous tannins, polyphenolic compounds, flavonoids, ellagic acid, triterpenoids, guiajaverin, quercetin, and other chemical compounds present in the plant are speculated to account for the observed antiinflammatory and analgesic effects of the plant's leaf extract. In summary, the findings of this experimental animal study indicate that the leaf aqueous extract of P. guajava possesses analgesic and antiinflammatory properties, and thus lend pharmacological credence to the suggested ethnomedical, folkloric uses of the plant in the management and/or control of painful, arthritic and other inflammatory conditions in some rural communities of Africa.

Topics: Acetic Acid; Analgesics; Analgesics, Opioid; Animals; Anti-Inflammatory Agents; Diclofenac; Female; Hindlimb; Hot Temperature; Inflammation; Injections, Intraperitoneal; Male; Mice; Mice, Inbred BALB C; Morphine; Ovalbumin; Pain; Pain Measurement; Phytotherapy; Plant Extracts; Plant Leaves; Psidium; Rats; Rats, Wistar; Water

1. The contribution of endogenous endothelins to nociceptive responses elicited by ovalbumin (OVA) in the hind-paw of mice sensitised to this antigen (50 microg OVA+5 mg Al(OH)(3), s.c., 14 days beforehand) was investigated. 2. Sensitised mice exhibited greater nocifensive responsiveness to intraplantar (i.pl.) OVA (total licking time over first 30 min: 85.2+/-14.6 s at 0.3 microg; 152.6+/-35.6 s at 1 microg) than nonsensitised animals (29.3+/-7.4 s at 1 microg). Nocifensive responses of sensitised mice to 0.3 microg OVA were inhibited by morphine (3 mg kg(-1), s.c.) or local depletion of mast cells (four daily i.pl. injections of compound 48/80). 3. Pretreatment with i.v. bosentan (mixed ET(A)/ET(B) receptor antagonist; 52 micromol kg(-1)) or A-122722.5 (selective ET(A) receptor antagonist; 6 micromol kg(-1)) reduced OVA-induced licking from 124.8+/-20.6 s to 45.7+/-13.0 s and 64.2+/-12.1 s, respectively, whereas A-192621.1 (selective ET(B) receptor antagonist; 25 micromol kg(-1)) enhanced them to 259.2+/-39.6 s. 4. Local i.pl. pretreatment with BQ-123 or BQ-788 (selective ET(A) or ET(B) receptor antagonists, respectively, each at 3 nmol) reduced OVA-induced licking (from 106.2+/-15.2 to 57.0+/-9.4 s and from 118.6+/-10.5 to 76.8+/-14.7 s, respectively). Sarafotoxin S6c (selective ETB receptor agonist, 30 pmol, i.pl., 30 min after OVA) induced nocifensive responses in OVA-sensitised, but not in nonsensitised, animals. 5. Compound 48/80 (0.3 microg, i.pl.) induced nocifensive responses per se and potentiated those induced by i.pl. capsaicin (0.1 microg). Treatment with BQ-123 (3 nmol, i.pl.) reduced only the hyperalgesic effect of compound 48/80, whereas BQ-788 (3 nmol) was ineffective. 6. Thus, immune-mediated Type I hypersensitivity reactions elicit mast cell- and endothelin-dependent nociception in the mouse hind-paw, which are mediated locally by both ET(A) and ET(B) receptors. The nocifensive response to antigen is amenable to blockade by systemic treatment with dual ET(A)/ET(B) or selective ET(A) receptor antagonists, but is sharply potentiated by systemic selective ET(B) receptor antagonist treatment. The apparently distinct roles played by ET(B) receptors in this phenomenon at local and other sites remain to be characterised.

Topics: Animals; Antigens; Bosentan; Dose-Response Relationship, Drug; Endothelins; Hyperalgesia; Hypersensitivity; Indicators and Reagents; Male; Mice; Oligopeptides; Ovalbumin; p-Methoxy-N-methylphenethylamine; Pain; Peptides, Cyclic; Piperidines; Sulfonamides; Viper Venoms

Effects of 3,5-dimethoxy-4-hydroxybenzoic acid and 2,3,4-trihydroxyacetophenone were studied on haemoglobin S (Hb S) polymerisation, analgesia and inflammation using Hb S solution, rats and mice. UV spectrophotometric procedure was used to monitor the polymerization of the Hb S. Acetic acid induced writhing in mice and egg albumin induced rat paw edema procedures were used to evaluate analgesic and anti-inflammatory activities of the compounds respectively. The results indicate that both drugs inhibit the process of polymerization significantly, possibly by direct action on the Hb S molecules. The drugs inhibited acetic acid induced pain and decreased egg albumin induced oedema. It is concluded that 3,5-dimethoxy-4-hydroxybenzoic acid and 2,3,4-trihydroxyacetophenone may have some value in the management of sickle cell disease.

Topics: Acetic Acid; Acetophenones; Analgesics; Anemia, Sickle Cell; Animals; Anti-Inflammatory Agents, Non-Steroidal; Antisickling Agents; Edema; Female; Guinea Pigs; Hemoglobin, Sickle; Humans; Hydroxybenzoates; Lethal Dose 50; Male; Mice; Ovalbumin; Pain; Rabbits; Rats; Rats, Wistar

The central nervous system regulates gut functions via complex interactions between the enteric nervous and immune systems. The aim of this study was to investigate whether mast cell mediators are released into the human jejunal lumen during stress.. A closed-segment perfusion technique was used to investigate jejunal release of tryptase, histamine, prostaglandin D2, and water flux in response to the cold pressor test in 8 healthy subjects and 9 patients with food allergy. In 6 food-allergic patients, jejunal biochemical responses to cold pain stress were compared with those induced by food intraluminal challenge.. Cold pain stress elevated heart rate and blood pressure and increased luminal release of mast cell mediators and jejunal water secretion in both groups. Stress-induced release of tryptase and histamine, but not of prostaglandin D2 and water flux, was greater in food-allergic patients than in healthy volunteers. In food-allergic patients, jejunal biochemical responses induced by cold pain stress were similar to those induced by antigen challenge.. These results show the ability of the central nervous system to modulate intestinal mast cell activity and suggest that mast cells have a role in stress-related gut dysfunction.

Topics: Adult; Body Water; Chymases; Cold Temperature; Female; Histamine Release; Humans; Jejunum; Male; Mast Cells; Neuropeptide Y; Ovalbumin; Pain; Serine Endopeptidases; Stress, Physiological; Tryptases

Hen egg white lysozyme (Fleming's lysozyme) was tested for antinociceptive activity in rats against foot hyperalgesia provoked by a subplantar injection of a number of irritants: arachidonic acid, brewer's yeast, carrageenan, kaolin, mepartricin and rabbit anti-rat serum (Randall-Selitto method). The compound was active when given p.o., i.m. or i.v. (100-200-400 mg/kg) as well as when injected locally in the foot pad concurrently with the irritant (1-2-4 mg/rat). Lysozyme decreased the sensitivity of the inflamed paw to the nociceptive stimulation, left unmodified the sensitivity of the normal paw and did not reduce the oedema of the inflamed paw. It differed in its activity from steroidal and non-steroidal anti-inflammatory drugs and from central analgesics that were used as standard reference drugs. Its activity was not shared by hen egg white and ovalbumin. Contrary to dextran, lysozyme i.p. did not induce anaphylactoid reactions. Lysozyme did not provoke tolerance and did not interfere with the antinociceptive activity of morphine. The results are in agreement with clinical data published years ago. Lysozyme was claimed to be an active agent against herpes zoster and cancer pain.

Topics: Analgesics; Animals; Arachidonic Acids; Chickens; Dextrans; Drug Evaluation, Preclinical; Egg White; Male; Morphine; Muramidase; Ovalbumin; Pain; Rats