Platelet Dysfunction in Chediak-Higashi Syndrome-Affected Cattle

Journal of Veterinary Medical Science

Masahiro IKEDA¹  Sachiko KAWASHIMA¹  Mitsuya SHIRAISHI¹  Hiroyuki OGAWA²  Katsuaki ITO¹ 

[1] Department of Veterinary Pharmacology, Faculty of Agriculture, Miyazaki University;Graduate School of Agriculture and Life Science, The University of Tokyo, Tokyo

关键词: Ca2+signaling;    cattle;    Chediak-Higashi syndrome;    collagen receptor;    platelet;   

DOI  :  10.1292/jvms.64.751

学科分类：兽医学

来源: Japanese Society of Veterinary Science

【 摘 要 】

References(73)Cited-By(9)A serious symptom of cattle affected with Chediak-Higashi syndrome (CHS) is a bleeding tendency. This diathesis is characterized by insufficient platelet aggregation as a result of depressed response to collagen. One possible cause for the depression is a decrease in contribution of endogenous agonists such as ADP or thromboxane A2, which are released following collagen stimulation. However, these endogenous agonists play only a minor role in collagen-induced aggregation of bovine platelets. More importantly, activation of phospholipase C as a result of a direct action of collagen is depressed, leading to a depression of Ca2+ mobilization, in platelets from CHS-affected cattle. Several types of collagen receptor are proposed to work in concert to induce aggregation. Among them, glycoprotein VI (GPVI) and GPIa/IIa (integrin α2 β1) have been supposed to play dominant roles in collagen-induced aggregation. However, there are arguments about the role of each receptor, especially the role of GPIa/IIa, and the crosstalk between receptors. Recently, we reported that the Ca2+ signaling produced by rhodocytin, which had been first reported to be an agonist for the collagen receptor GPIa/IIa, produced much less Ca2+ signaling in CHS platelets than in normal ones, whereas that produced by GPVI activators was normal. These suggest that GPIa/IIa or the rhodocytin-associated pathway is impaired in CHS platelets. CHS platelets are valuable to reassess the mechanism of collagen-dependent signal transduction system and to delineate the inter-relationship among collagen receptors.

【 授权许可】

Unknown