Platelet-Activating Factor: Receptors and Receptor Antagonists

Hwang, San-Bao

doi:10.1016/b978-0-12-198875-3.50015-3

Cited by 5 publications

(11 citation statements)

References 318 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For instance, the PAF response of human PMN (chemotaxis, superoxide production, and degranulation) is abolished by pertussis toxin (which inactivates the Gi subunit of Gproteins), whereas human platelet responses (aggregation and degranulation) are unaffected by this agent (Hwang, 1994). Thus, it is likely that the diversity of G-proteins coupled to a given PAF receptor modulates more than one signal transduction pathway.…”

Section: (I) Introductionmentioning

confidence: 99%

“…And, when released extracellularly, fluid-phase PAF can act in a paracrine manner. Nakamura et al, 1991;Ye et al, 1991;Chao and Olson, 1993;Bito et al, 1994;Hwang, 1994;Izumi and Shimizu, 1995;Ishii et al, 1996;Shimizu and Mutoh, 1997). Interestingly, two different transcripts of this gene have been identified (cf.…”

Section: (I) Introductionmentioning

confidence: 99%

“…PAF receptors were originally characterized in bioassay or radioligand binding studies which frequently used specific PAF receptor antagonists (cf. Hwang, 1994). However, since a PAF receptor (PAFR) gene has now been identified on chromosome 1 Nakamura et al, 1991;Ye et al, 1991;Chao and Olson, 1993;Bito et al, 1994;Izumi and Shimizu, 1995;Ishii et al, 1996;Shimizu and Mutoh, 1997), more comprehensive features of this PAF receptor are now recognized.…”

Section: (I) Introductionmentioning

confidence: 99%

“…In brief, bioassay and receptor binding studies indicated the existence of multiple PAF receptors or PAF receptors with different PAF affinities (cf. Hwang, 1994); and structure-activity relationship studies demonstrated significant differences in the rank order or potency of six molecular species of alkyl-PAF and acyl-PAF relative to the stimulation of several functional responses by human PMN (Pinckard et al, 1992McManus et at., 1993b). In combination, these findings suggested the existence of PAF receptor subtypes in human PMN.…”

Section: (I) Introductionmentioning

confidence: 99%

“…However, both rat liver and PMN express specific PAF binding sites (cf. Hwang, 1994). Clearly, PAF receptor heterogeneity could provide an additional mechanism for modulation of PAF-induced (patho)physiological responses.…”

Section: (I) Introductionmentioning

confidence: 99%

See 4 more Smart Citations

PAF, a Putative Mediator of Oral Inflammation

McManus

Pinckard

2000

Critical Reviews in Oral Biology & Medicine

View full text Add to dashboard Cite

PAF, or platelet-activating factor, is a family of structurally related phospholipids (1 -O-alkyl/acyl/alkenyl-2-acetylsn-glycero-3-phosphocholine) which possesses a wide spectrum of potent pro-inflammatory actions. These phospholipids are synthesized by a diverse array of cells, including neutrophilic polymorphonuclear leukocytes (PMN), platelets, mast cells, monocytes/macrophages, vascular endothelial cells, and lymphocytes. PAF targets these and other cells via specific, G-proteincoupled receptors to initiate intracrine, autocrine, paracrine, and juxtacrine cell activation. Of importance, these unique acetylated phospholipids are frequently synthesized in concert with pro-inflammatory lipid mediators derived from arachidonic acid. Since PAF synergizes with these and other mediators to amplify the inflammatory response, it seems likely that PAF plays an integral, perhaps pivotal, role in acute and chronic inflammatory processes. PAF is present in the mixed saliva of dentate, but not edentulous, human subjects. The levels of PAF in mixed saliva or in gingival crevicular fluid and tissues are significantly increased during oral inflammatory conditions such as periodontitis and mucositis. Interestingly, the levels of salivary PAF correlate with the extent/severity of these oral diseases. These observations suggest that PAF may participate in pathophysiologic events during the course of oral inflammation. The availability of specific PAF receptor antagonists and human recombinant PAF-acetylhydrolase (PAF-AH), a plasma enzyme which rapidly destroys PAF, should provide clinical tools for the investigation of the role of PAF in these and other inflammatory disorders; and perhaps, ultimately, some of these reagents may prove to be therapeutically useful in the treatment and management of these conditions.

show abstract

Section: (I) Introductionmentioning

confidence: 99%

Section: (I) Introductionmentioning

confidence: 99%

Section: (I) Introductionmentioning

confidence: 99%

Section: (I) Introductionmentioning

confidence: 99%

Section: (I) Introductionmentioning

confidence: 99%

See 3 more Smart Citations

PAF, a Putative Mediator of Oral Inflammation

McManus

Pinckard

2000

Critical Reviews in Oral Biology & Medicine

View full text Add to dashboard Cite

show abstract

PAF‐induced inflammatory and immuno‐allergic ophthalmic diseases and their mitigation with PAF receptor antagonists: Cell and nuclear effects

Sharif

2022

BioFactors

View full text Add to dashboard Cite

Ocular allergies are becoming more prevalent as more airborne pollutants, irritants and microbes pervade our environment. Inflammatory and allergic mediators released by dendritic and mast cells within the conjunctiva cause allergic conjunctivitis (AC), a prevalent ocular surface disorder that affects >40% of the world's human population on a seasonal or perennial basis. Even though histamine is a major culprit, platelet‐activating factor (PAF) also contributes to AC, acting either directly or synergistically with histamine and other mediators. PAF receptor‐meditated inflammatory reactions, via cell‐membrane‐bound and nuclear‐membrane‐bound and nuclear PAF receptors, are also implicated in the etiology of other eye diseases such as uveitis, diabetic retinopathy, corneal and choroidal neovascularization, and age‐related macular degeneration which cause serious visual impairment and can lead to blindness. This review highlights the various deleterious elements implicated in the pathological aspects of ocular allergic reactions and inflammation and provides concepts and treatment options to mitigate these eye disorders with a special focus on PAF and PAF receptor antagonists.

show abstract