Strain differences in concanavalin a-induced paw edema in the rat: Involvement of histamine H1 and H2 receptors

Abstract

The present study tests the hypothesis that the difference in the intensity of paw edema found between the Dark Agouti (DA) and Albino Oxford (AO) rat strains originates from the distinct participation of histamine, serotonin and their corresponding receptors in Concanavalin A (Con A)-induced inflammation. DA and AO male rats were intraplantarly injected with specific receptor antagonists prior to Con A, and the intensity of inflammation was determined by measuring the paw diameter. Our results have showed that histamine H1 and H2 receptor antagonists reduced the Con A-induced paw edema in DA rats, while serotonin 5HT3 receptor antagonist diminished the inflammation in both DA and AO rat strains. The calcium channel blocker did not change Con A-induced inflammation. Strain differences in the intensity and kinetics of inflammation observed between the DA and AO rats are most likely defined by the diversity of mediators released and their receptors activated upon Con A injection.

Testirana je hipoteza da razlike u intenzitetu inflamatornog edema šape indukovanog konkanavalinom A u pacova Dark Agouti (DA) i Albino Oxford (AO) soja potiču od različitog doprinosa histamina i serotonina i njihovih odgovarajućih receptora. Mužjaci pacova DA i AO soja su intraplantarno tretirani antagonistima specifičnih receptora pre izazivanja inflamacije konkanavalinom A i intenzitet inflamacije je praćen merenjem dijametra šape. Naši rezultati su ukazali da antagonisti histaminskih H1 i H2 receptora smanjuju edem šape indukovan konkanavalinom A u DA pacova, dok antagonist serotoninskih 5HT3 receptora smanjuje edem šape u oba soja pacova. Blokator kalcijumskih kanala ne utiče na inflamaciju izazvanu konkanavalinom A. Razlike u intenzitetu i kinetici inflamatornog odgovora indukovanog konkanavalinom A između DA i AO sojeva su najverovatnije posledica razlika u oslobođ enim medijatorima i aktivaciji odgovarajućih receptora nakon injekcije konkanavalina A.