Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0033774 (pruritus)
 14,546 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Thirteen adults with dermatitis herpetiformis (DH) controlled by dapsone or sulphamethoxypyridazine were given indomethacin or placebo in a double-blind cross-over study. In nine of the thirteen patients the rash and pruritus of DH were exacerbated more by indomethacin than by placebo. Dapsone and sulphamethoxypyridazine requirements were increased during the indomethacin period. The involvement of lipoxygenase products in the pathogenesis of the DH skin lesions is postulated.
 ...
PMID:Dermatitis herpetiformis exacerbated by indomethacin. 399 20

The term ocular allergy encompasses a group of diseases in which there is a high frequency of atopy, ocular itching, stringy discharge and a papillary conjunctival reaction. Conditions confined to the lids and conjunctiva (e.g. seasonal allergic conjunctivitis) have a good prognosis but those involving the cornea may result in visual impairment (e.g. atopic keratoconjunctivitis). Mast cell and eosinophil mechanisms are important in al the ocular allergies, but T cell inflammation is prominent only in vernal keratoconjunctivitis, atopic keratoconjunctivitis and giant papillary conjunctivitis. Therapy involves the use of antigen avoidance (where possible), nonspecific medical therapy (e.g. cold compresses, artificial tears), specific medical therapy and, in certain situations, immunotherapy and surgery. Topical antihistamines (often in combination with a vasoconstrictor) and oral antihistamines are widely used in perennial and seasonal conjunctivitis. Levocabastine is a new preparation which is more rapid and potent. Mast cell inhibitors [e.g. sodium cromoglycate (cromolyn sodium)] have a proven track record as safe and effective therapy for all ocular allergic diseases and the newer, more potent nedocromil and lodoxamide are now available. Topical steroids are only indicated in sight-threatening disease due to their serious adverse effects and other therapy should be continued to minimise the dose required. There is a lack of intermediate potency and high potency but safe topical preparations. A number of future possibilities exist, some of which have been partially explored. Cyclo-oxygenase inhibitors have proved of limited use, but inhibitors of lipoxygenase and kinin pathways are awaited. Although results with HEPP have been disappointing, other modulators of mast cell function (e.g. picumast, beta-agonists and phosphodiesterase inhibitors) may prove useful in the future. So far, results with topical cyclosporin in serious disease are very encouraging. Future developments in the manipulation of eosinophilic products, cytokines and adhesion molecules may also be relevant. However, the current situation for those with serious ocular allergy remains a disturbing dependence upon topical steroids, with all the attendant risks.
 ...
PMID:Therapeutic options in ocular allergic disease. 852 55

Histamine is known to excite a subset of C-fibers and cause itch sensation. Despite its well-defined excitatory action on sensory neurons, intracellular signaling mechanisms are not understood. Previously, we demonstrated that bradykinin excited sensory neurons by activating TRPV1 via the phospholipase A(2) (PLA(2)) and lipoxygenase (LO) pathway. We, thus, hypothesized that histamine excited sensory neurons via the PLA(2)/LO/TRPV1 pathway. Application of histamine elicited a rapid increase in intracellular Ca(2+) ([Ca(2+)](i)) that desensitized slowly in cultured dorsal root ganglion neurons. Histamine-induced [Ca(2+)](i) was dependent on extracellular Ca(2+) and inhibited by capsazepine and by SC0030, competitive antagonists of TRPV1. Quinacrine and nordihydroguaiaretic acid, a PLA(2) and an LO inhibitor, respectively, blocked the histamine-induced Ca(2+) influx in sensory neurons, while indomethacin (a cyclooxygenase inhibitor) did not. We thus conclude that histamine activates TRPV1 after stimulating the PLA(2)/LO pathway, leading to the excitation of sensory neurons. These results further provide an idea for potential use of TRPV1 antagonists as anti-itch drugs.
 ...
PMID:Histamine-induced Ca(2+) influx via the PLA(2)/lipoxygenase/TRPV1 pathway in rat sensory neurons. 1513 18