Macrophage activation reduces mobilization of arachidonic acid by guinea-pig and rat peritoneal macrophagesin vitro

Abstract

We have examined species differences in the mobilization of arachidonic acid and generation of prostacyclin in non-activated and activated peritoneal macrophages in vitro. Mobilization of 3H-arachidonic acid was reduced in rat activated macrophages compared with that in non-activated macrophages, but a similar difference was not observed in guinea-pig macrophages. In guinea-pig peritoneal macrophages, exposure to formyl-Methionyl-Leucyl-Phenylalanine (fMLP), platelet-activating factor (Paf), zymosan and A23187 increased the generation of prostacyclin. In contrast, in rat peritoneal macrophages, fMLP and Paf did not stimulate the mobilization of arachidonic acid or the generation of prostacyclin, whereas both zymosan and A23187 were effective stimuli. Pretreatment of either rats or guinea-pigs by intraperitoneal injection of C. Parvum reduced prostacyclin generation by peritoneal macrophages in vitro. We conclude that there may be species differences in receptor populations between guinea-pig and rat peritoneal macrophages. However, the reduction in eicosanoid generation induced by the inflammatory stimulus, C. Parvum is not species-dependent.

Synthesis of Novel Derivatives of Aroylaminoalcohols and 3-Amino-substituted 1-Phenylpropanols with Potential Anti-inflammatory and Immunomodulating Activities

“…We found that when compound 2 was added to cultures of macrophages from arthritic rats the amounts of IL-1 produced were greater than by the control group. These findings suggest that compound 2 resembles the classical cycloxygenase inhibitors, which increase the production of IL-1 (Dinarello et a1 1984;Lim & Stewart 1990). In contrast, the presence of compound 4 suppressed the production of IL-1 from normal and arthritic rats, indicating a possible inhibitory effect on macrophages; this differentiates compound 4 from compound 2.…”

Nitrite is produced by elicited but not by circulating neutrophils

“…Isolation of rat elicited PMNs and macrophages Peritoneal macrophages were isolated from rats according to previously described methods. 26 Briefly, male Sprague-Dawley rats (150-300g) received an injection of oyster glycogen dissolved in phosphate buffered saline (PBS, 10ml, 2%, i.p.). Oyster glycogen prepared at this concentration did not contain detectable endotoxin (less than 100 pg/ml),…”

Συνθεση Φαρμακοχημικη Μελετη Και Βιολογικος Ελεγχος Ενωσεων Με Πιθανη Δραση Στο Ανοσοβιολογικο Συστημα

“…Η ανασταλτική δράση των ενώσεων στις 4 ώρες εμφανίζει τάση συσχέτισης με τις θεωρητικές τιμές λιποφιλικότητα, όπως φαίνεται από την εξίσωση (7) Συνοψίζοντας τα παραπάνω, συμπεραίνομε ότι η λιποφιλικότητα συσχετίζεται γραμμικά με την έκφραση της αντιφλεγμονώδους δράσης των εξεταζόμενων απελευθέρωση προσταγλανδινών, λευκοτριενίων και προστακυκλίνης, που στη συνέχεια ρυθμίζουν τη δράση των μακροφάγων και την παραγωγή της IL-1 [260]. Έχει αναφερθεί ότι στη δοκιμασία ανίχνευσης της IL-1, όπου χρησιμοποιούνται τα θυμοκύτταρα, παράγοντες που υπάρχουν στο υπερκείμενο-IL-l, όπως PGE2, παρεμποδίζουν τον πολλαπλασιασμό των κυττάρων αυτών καθώς και την παραγωγή της IL-1 από τα μακροφάγα [149,261,262].…”