Angiotensin II desensitization and Ca2+ and Na+ fluxes in vascular smooth muscle cells

التفاصيل البيبلوغرافية
العنوان: Angiotensin II desensitization and Ca2+ and Na+ fluxes in vascular smooth muscle cells
المؤلفون: Aboulafia, J., Oshiro, M. E. M., Feres, T., Shimuta, S. I., Paiva, A. C. M.
المصدر: Pflügers Archiv European Journal of Physiology; November 1989, Vol. 415 Issue: 2 p230-234, 5p
مستخلص: The role of ion fluxes in angiotensin II (AII) desensitization (tachyphylaxis) was investigated by studying Na+ and Ca2+ translocation in cultured vascular smooth muscle cells from the rat aorta. The effects of AII were compared to those of [1-sarcosine]-AII (Sar1-AII), an analogue which also induces tachyphylaxis, and [2-lysine]-AII (Lys2-AII), an analogue that does not show this property. Maximally effective concentrations of the three peptides induced a rapid and transient increase in 45Ca2+ efflux, a rapid and sustained decrease in total cell Ca2+ and an increased Na+ permeability. Repeated treatments, at short intervals, with either of the three peptides abolished the effect on Ca2+ efflux, and this desensitization was slowly reversible. A 30-min rest period was sufficient for full recovery of the response of cells that were desensitized by Lys2AII, whereas the recovery from AII or Sar1AII-desensitization was still not complete after 60 min. Our results suggest that the difference in the behaviour of the “tachyphylactic” AII and Sar1-AII and the “non-tachyphylactic” Lys2-AII lays not in the production of different signals upon binding to the receptor, but in a difference in the hormone-receptor interaction itself.
قاعدة البيانات: Supplemental Index
الوصف
تدمد:00316768
14322013
DOI:10.1007/BF00370597