title: Immunomodulatory role of substance P in the wall lizard Hemidactylus flaviviridis: an in vitro study.
abstract: Present in vitro investigation for the first time in ectotherms demonstrated the immunomodulatory role of substance P in the wall lizard Hemidactylus flaviviridis. Substance P inhibited the percentage phagocytosis and phagocytic index of lizard splenic phagocytes. Inhibitory effect of substance P was completely blocked by NK-1 receptor antagonist spantide I, indicating the NK-1 receptor mediated action. Further, NK-1 receptor-coupled downstream signaling cascade involved in controlling phagocytosis was explored using inhibitors of adenylate cyclase (SQ 22536) and protein kinase A (H-89). Both the inhibitors, in a concentration-related manner decreased the suppressive effect of substance P on phagocytosis. In addition, substance P treatment caused an increase in intracellular cAMP level in splenic phagocytes. Taken together, it can be suggested that substance P via NK-1 receptor-coupled AC-cAMP-PKA pathway modulated the phagocytic activity of splenic phagocytes in wall lizards.
authors.affiliation: Department of Zoology, University of Delhi, Delhi, India.
authors.forename: Sunil
authors.initials: S
authors.lastname: Kumar
authors.forename: Umesh
authors.initials: U
authors.lastname: Rai
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives / Q000494:pharmacology; D000818:Animals; D002478:Cells, Cultured; D000242:Cyclic AMP / Q000032:analysis / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005260:Female; D007155:Immunologic Factors / Q000378:metabolism / Q000494:pharmacology; D007546:Isoquinolines / Q000494:pharmacology; D008116:Lizards / Q000276:immunology*; D064729:Neurokinin-1 Receptor Antagonists; D010586:Phagocytes / Q000187:drug effects / Q000378:metabolism; D010587:Phagocytosis / Q000187:drug effects / Q000276:immunology; D018040:Receptors, Neurokinin-1 / Q000276:immunology; D015398:Signal Transduction / Q000187:drug effects / Q000276:immunology; D013154:Spleen / Q000187:drug effects / Q000276:immunology; D013373:Substance P / Q000031:analogs & derivatives / Q000276:immunology* / Q000494:pharmacology; D013449:Sulfonamides / Q000494:pharmacology
chemical_list: D004791:Enzyme Inhibitors; D007155:Immunologic Factors; D007546:Isoquinolines; D064729:Neurokinin-1 Receptor Antagonists; D018040:Receptors, Neurokinin-1; D013449:Sulfonamides; C017759:9-(tetrahydro-2-furyl)-adenine; D013373:Substance P; C042867:spantide; D000242:Cyclic AMP; D000225:Adenine; C063509:N-(2-(4-bromocinnamylamino)ethyl)-5-isoquinolinesulfonamide