title: [Effects of sodium hyaluronate on the nociceptive response of rats with experimentally induced arthritis].
abstract: Antinociceptive effects of sodium hyaluronate (Na-HA) were studied on the basis of improvement in the graded abnormal gait elicited by arthritis induced by intra-articular administration of monosodium urate crystal (MSU) to rats. One hour before MSU injection, intra-articular administration of a 1.0% solution of Na-HA with different molecular weights, ranging from 4.70 x 10(5) to 2.02 x 10(6) (HA-200), improved the score of abnormal gait in a molecular weight-dependent manner in the experimental arthritis model. Similarly, administrations of HA-200 at concentrations ranging from 0.1 to 1.0% prior to MSU treatment resulted in improvement of the score in abnormal gait in a dose-dependent manner. To elucidate the antinociceptive mechanisms of Na-HA, effects of pretreatment with Na-HA (1.0%) of different molecular weights on prostaglandin E2 (PGE2) and bradykinin (BK) releases in synovial fluid 3 hr after MSU injection were studied. Increases in PGE2 and BK concentration in the synovial fluid were depressed in a molecular weight-dependent manner by Na-HA (1.0%) pretreatment. These results indicate that Na-HA attenuates the nociceptive responses inflicted by the MSU-induced arthritis. Such an antinociceptive effect may be due to the inhibition of PGE2 and BK synthesis in the synovial joint of rats.
authors.affiliation: Division of Pharmacology, Research Laboratories, Maruho Co., Ltd., Osaka, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Aihara
authors.forename: N
authors.initials: N
authors.lastname: Murakami
authors.forename: R
authors.initials: R
authors.lastname: Ishii
authors.forename: K
authors.initials: K
authors.lastname: Kariya
authors.forename: Y
authors.initials: Y
authors.lastname: Azuma
authors.forename: K
authors.initials: K
authors.lastname: Hamada
authors.forename: J
authors.initials: J
authors.lastname: Umemoto
authors.forename: S
authors.initials: S
authors.lastname: Maeda
mesh_terms: D000700:Analgesics / Q000494:pharmacology / Q000627:therapeutic use*; D000818:Animals; D001168:Arthritis / Q000139:chemically induced / Q000188:drug therapy* / Q000378:metabolism; D001920:Bradykinin / Q000378:metabolism; D015232:Dinoprostone / Q000378:metabolism; D006820:Hyaluronic Acid / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use*; D008297:Male; D008970:Molecular Weight; D051381:Rats; D017208:Rats, Wistar; D013582:Synovial Fluid / Q000378:metabolism; D014527:Uric Acid
chemical_list: D000700:Analgesics; D014527:Uric Acid; D006820:Hyaluronic Acid; D015232:Dinoprostone; D001920:Bradykinin