Submit a Letter to the Editor for:
Wolfgang M. Kuebler, Kaushik Parthasarathi, Ping M. Wang, Jahar Bhattacharya
J Clin Invest. 2000;
105(7):905
doi:10.1172/JCI8604
Abstract |
Full text
|
PDF
P
ropagation of inflammatory signals from the airspace to the vascular space is pivotal in lung inflammation, but mechanisms of intercompartmental signaling are not understood. To define signaling mechanisms, we microinfused single alveoli of blood-perfused rat lung with TNF-α, and determined in situ cytosolic Ca2+ concentration ([Ca2+]i) by the fura-2 ratio method, cytosolic phospholipase A2 (cPLA2) activation and P-selectin expression by indirect immunofluorescence. Alveolar TNF-α increased [Ca2+]i and activated cPLA2 in alveolar epithelial cells, and increased both endothelial [Ca2+]i and P-selectin expression in adjoining perialveolar capillaries. All responses were blocked by pretreating alveoli with a mAb against TNF receptor 1 (TNFR1). Crosslinking alveolar TNFR1 also increased endothelial [Ca2+]i. However, the endothelial responses to alveolar TNF-α were blocked by alveolar preinjection of the intracellular Ca2+ chelator BAPTA-AM, or the cPLA2 blockers AACOCF3 and MAFP. The gap-junction uncoupler heptanol had no effect. We conclude that TNF-α induces signaling between the alveolar and vascular compartments of the lung. The signaling is attributable to ligation of alveolar TNFR1 followed by receptor-mediated [Ca2+]i increases and cPLA2 activation in alveolar epithelium. These novel mechanisms may be relevant in the alveolar recruitment of leukocytes.
Guidelines:
The Editorial Board will only consider letters that we deem relevant and of interest to our readers. We will not post data that have not been subjected to peer review, nor will we post letters that are essentially a reiteration of another letter. All accepted letters will be posted on our website within one week of acceptance. The Editors reserve the right to edit any letter for length, content, and clarity. Authors of all accepted letters will be asked to preview any changes. Authors will be notified by e-mail if their letters were not accepted. As this is a final decision, no appeals will be considered.
Specific requirements: All letters must be 400 words or fewer. You may enter the letter as plain text or HTML, if you wish. The author's name and e-mail address are required, and will be posted with the letter. All possible conflicts of interest must be noted, even if they are not posted. If you wish to include a figure (keep in mind that non-peer-reviewed data will not be posted), please contact the editor directly at editors@the-jci.org.
