PT - JOURNAL ARTICLE AU - Lorraine Mcmurdo AU - Alan H. Stephenson AU - Joseph J. Baldassare AU - Randy S. Sprague AU - Andrew J. Lonigro TI - Biosynthesis of Sulfidopeptide Leukotrienes Via the Transfer of Leukotriene A<sub>4</sub> from Polymorphonuclear Cells to Bovine Retinal Pericytes DP - 1998 Jun 01 TA - Journal of Pharmacology and Experimental Therapeutics PG - 1255--1259 VI - 285 IP - 3 4099 - http://jpet.aspetjournals.org/content/285/3/1255.short 4100 - http://jpet.aspetjournals.org/content/285/3/1255.full SO - J Pharmacol Exp Ther1998 Jun 01; 285 AB - Administration of exogenous sulfidopeptide leukotrienes (LTs) is associated with enhanced microvascular permeability. In addition, endogenous LTs have been implicated as participants in permeability (nonhydrostatic) edema formation. The source of LTs for interaction with the microvasculature is, however, unknown. We hypothesized that pericytes contribute to vascular LT synthesis. Under basal conditions and after incubation with either the calcium ionophore, A23187 (0-1 μM), or arachidonic acid (20 μM), bovine retinal pericytes (BRPs) did not produce significant amounts of sulfidopeptide LTs. In contrast, in the presence of polymorphonuclear leukocytes (PMNs), which can synthesize LTA4, but not sulfidopeptide leukotrienes, incubation of BRPs with A23187 resulted in dose-dependent increases in LTC4/D4/E4 production (peak: 35.4 ± 5 pg/μg protein; n = 12). Similarly, BRPs, incubated with exogenous, authentic LTA4 (10 μM), synthesized sulfidopeptide LTs (peak: 18.9 ± 5 pg/μg protein,n = 3). Preincubation (30 min) of BRPs with PMNs and the lipoxygenase inhibitor, esculetin (1 × 10−4 M; n = 12), reduced peak A23187-induced production of LTs by 63.9 ± 7%. Finally, Northern blot analysis revealed mRNA for 5-lipoxygenase to be present in human and bovine PMNs, but not in BRPs. These results suggest that pericytes produce sulfidopeptide LTs only when provided with LTA4 from an external source such as the PMN. Interactions between pericytes and PMNs may lead to the production of sulfidopeptide LTs, which, in turn, could alter microvascular permeability. The American Society for Pharmacology and Experimental Therapeutics