title: Annexin I is a local mediator in neural-endocrine feedback control of inflammation.
abstract: Annexin I is a local mediator in neural-endocrine feedback control of inflammation. J. Neurophysiol. 80: 3120-3126, 1998. Activation of primary afferent nociceptors induces a neural endocrine-mediated inhibition of the inflammatory response via a circuit that includes ascending spinal pathways and activation of the hypothalamic-pituitary adrenal (HPA) axis. This circuit inhibits sympathetic neuron-dependent plasma extravasation (PE) in the rat knee joint produced by bradykinin (BK), but not sympathetic neuron-independent PE produced by platelet activating factor (PAF). Noxious (25 mA) but not non-noxious (2.5 mA) electrical stimulation significantly increased plasma corticosterone concentrations, and intravenous infusion of corticosterone (5 micrograms/min) mimicked inhibition of BK-induced PE produced by noxious stimulation. However, perfusion of corticosterone locally through the knee joint, at doses that do not have a systemic action (i.e., </=1 microM), did not inhibit BK-induced PE. Annexin I (lipocortin-1), a 37-kDa member of a family of phospholipid and calcium binding proteins, can mediate local anti-inflammatory effects of glucocorticoids via a mechanism that is partially dependent on inhibition of phospholipase A2 activity and adhesion and transmigration of polymorphonuclear leukocytes. Because BK-induced PE is dependent on both polymorphonuclear leukocytes and phospholipase A2 activity, we tested the hypothesis that the action of corticosterone to inhibit BK-induced PE is mediated by stimulating the production and release of annexin I. Perfusion of BK (150 nM) through the rat knee joint induces a rapid and sustained increase in PE. Co-perfusion of BK with annexin I (100 ng/ml) through the knee joint mimics the inhibition of BK-induced PE produced by noxious electrical stimulation or by intravenous corticosterone. Co-perfusion of BK with annexin I antibody (LCPS1, 1:60 dilution) prevented the inhibition of BK-induced PE produced by noxious electrical stimulation or intravenous corticosterone adminstration. PAF-induced PE, which is not dependent on polymorphonuclear leukocytes, was not inhibited by local perfusion of annexin I. These data suggest that the inhibitory effect of C-fiber activity on BK-induced PE, acting via an HPA circuit, is mediated by annexin I in the knee joint.
authors.affiliation: Department of Oral and Maxillofacial Surgery, University of California San Francisco, San Francisco, California 94143-0440, USA.
authors.forename: P G
authors.initials: PG
authors.lastname: Green
authors.forename: H J
authors.initials: HJ
authors.lastname: Strausbaugh
authors.forename: J D
authors.initials: JD
authors.lastname: Levine
mesh_terms: D000818:Animals; D017305:Annexin A1 / Q000502:physiology*; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology; D001920:Bradykinin / Q000037:antagonists & inhibitors / Q000494:pharmacology; D002199:Capillary Permeability / Q000187:drug effects / Q000502:physiology; D003345:Corticosterone / Q000378:metabolism / Q000494:pharmacology; D004558:Electric Stimulation; D005246:Feedback / Q000502:physiology*; D007249:Inflammation / Q000503:physiopathology*; D007270:Injections, Intra-Articular; D008297:Male; D009490:Neurosecretory Systems / Q000502:physiology* / Q000503:physiopathology; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D017305:Annexin A1; D000894:Anti-Inflammatory Agents, Non-Steroidal; D001920:Bradykinin; D003345:Corticosterone