tailieunhanh - Báo cáo y học: "IGF-1 regulates cAMP levels in astrocytes through a β2-adrenergic receptor-dependant mechanism"

Tuyển tập các báo cáo nghiên cứu khoa học ngành y học tạp chí Medical Sciences dành cho các bạn sinh viên ngành y tham khảo đề tài: IGF-1 regulates cAMP levels in astrocytes through a β2-adrenergic receptor-dependant mechanism. | Int. J. Med. Sci. 2008 5 240 Short Research Communication International Journal of Medical Sciences ISSN 1449-1907 2008 5 5 240-243 Ivyspring International Publisher. All rights reserved IGF-1 regulates cAMP levels in astrocytes through a p2-adrenergic receptor-dependant mechanism Daniel Chesik Nadine Wilczak and Jacques De Keyser Department of Neurology University Medical Center Groningen Hanzeplein 1 9713 GZ Groningen the Netherlands Correspondence to Daniel Chesik Department of Neurology University Medical Center Groningen Hanzeplein 1 9713 GZ Groningen The Netherlands. Tel. 0031-50-3637719 Fax 0031-50-3611707 e-mail Received Accepted Published We have recently demonstrated that neonatal astrocytes derived from mice lacking beta-2 adrenergic receptors P2AR possess higher proliferation rates as compared to wild-type cells an attribute that was shown to involve insulin-like growth factor IGF signaling. In the present study we demonstrate that basal cAMP levels in P2AR knockout astrocytes were significantly lower than in wild type cells. Furthermore treatment with IGF-1 reduced intracellular cAMP levels in wild type astrocytes yet had no effects on cAMP levels in P2AR deficient astrocytes. Our data suggests that IGF-1 treatment influences cAMP production through a P2AR-dependant mechanism in astrocytes. A deficit of P2AR on astrocytes as previously reported in multiple sclerosis may influence cell proliferation an action which could have implications in processes involved in astrogliosis. Key words beta adrenergic receptors insulin-like growth factor cyclic adenosine monophosphate astrocytes multiple sclerosis Introduction Beta-adrenergic receptors PARs are members of the superfamily of G-protein coupled receptors GPCRs and involved in fundamental processes such as cell growth differentiation and metabolism. They are stimulated by catecholamines epinephrine and norepinephrine NE and play important