MEDIATORS OF ACUTE INFLAMMATION AND THEIR ROLES IN MODULATING IN VI3^ LEUKOCYTE INFILTRATION AND PATHOBIOLOGIC ACTIVITY IN THE CONJUNCTIVA
type: CreativeWork
description: Several substances alter leukocyte motility, but the relative importance of these putative meditors during acute inflammation remains unclear. The present study investigated the roles of several candidate mediators within the context of Type I allergic conjunctival leukocyte infiltration and pathobiologic activity in the guinea pig. Histamine and the leukotrienes (LTs) were found to be the likely important primary mediators of leukocyte emigration into conjunctival tissues. The prostaglandins (PGs) and platelet-activating factor (PAF) tailed to elicit pronounced conjunctival leukocyte infiltration, and leukocytes did not respond to any of the forms of the eosinophil chemotactic factor of anaphylaxis (ECF-A) or bradykinin (BK). Histamine elicited a dose-dependent conjunctival infiltrate which was pre-dominantly eosinophilic. Peak emigration occurred at six hours after treatment, at which time significant damage to the conjunctival epithelium and depletion of goblet cell numbers was correlated with the presence of degranulated and fragmenting eosinophils. In animals presensitized to ovalbumin, antigen challenge evoked extensive accumulations of degranulated and fragmenting eosinophils concurrent with exfoliation and pitting of the epithelium and goblet cell expulsion. Neither pyrilamine nor cimetidine alone produced an inhibitory effect or prevented tissue damage but a combination of these antagonists resulted in a significant reduction of eosinophil numbers and also prevented epithelial damage and depletion of goblet cells associated with Type I allergy. The peptide-containing LTs, LTD4 and LTE4, elicited dose-dependent and exclusively eosinophilic conjunctival infiltrates. Infiltrating eosinophils appeared intact and no instances of epithelial damage were ever observed in LT-treated tissues. LTB4 proved to be less potent in causing cellular infiltration, into the conjunctiva. The slow-reacting substance of anaphylaxis (SRS-A) antagonist, FPL 55712, and the potent an…
abstract: Several substances alter leukocyte motility, but the relative importance of these putative meditors during acute inflammation remains unclear. The present study investigated the roles of several candidate mediators within the context of Type I allergic conjunctival leukocyte infiltration and pathobiologic activity in the guinea pig. Histamine and the leukotrienes (LTs) were found to be the likely important primary mediators of leukocyte emigration into conjunctival tissues. The prostaglandins (PGs) and platelet-activating factor (PAF) tailed to elicit pronounced conjunctival leukocyte infiltration, and leukocytes did not respond to any of the forms of the eosinophil chemotactic factor of anaphylaxis (ECF-A) or bradykinin (BK). Histamine elicited a dose-dependent conjunctival infiltrate which was pre-dominantly eosinophilic. Peak emigration occurred at six hours after treatment, at which time significant damage to the conjunctival epithelium and depletion of goblet cell numbers was correlated with the presence of degranulated and fragmenting eosinophils. In animals presensitized to ovalbumin, antigen challenge evoked extensive accumulations of degranulated and fragmenting eosinophils concurrent with exfoliation and pitting of the epithelium and goblet cell expulsion. Neither pyrilamine nor cimetidine alone produced an inhibitory effect or prevented tissue damage but a combination of these antagonists resulted in a significant reduction of eosinophil numbers and also prevented epithelial damage and depletion of goblet cells associated with Type I allergy. The peptide-containing LTs, LTD4 and LTE4, elicited dose-dependent and exclusively eosinophilic conjunctival infiltrates. Infiltrating eosinophils appeared intact and no instances of epithelial damage were ever observed in LT-treated tissues. LTB4 proved to be less potent in causing cellular infiltration, into the conjunctiva. The slow-reacting substance of anaphylaxis (SRS-A) antagonist, FPL 55712, and the potent an…
author: Spada, Clayton Samuel
license: https://dora.dmu.ac.uk/bitstreams/63596796-fa8d-46c4-a33d-fb59b9e474d9/download
date published: 1990-08
date modified: 2026-07-24T06:18:24Z
provider: De Montfort University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: De Montfort University