[Polyamines antagonizing angiotensin II contractile effects in isolated rat aorta].
Our study showed that the administration in pre-treatment of some polyamines (especially spermine and spermidine and almost null agmatine, putrescine and cadaverine) reduced the contractile effects of angiotensin II (Ang II) in isolated rat aorta. These effects might not be associated to the interference of clathrin coated vesicles (coated pits) formation or caveolae interaction (and thus to Ang II internalization through AT1 receptors). In contrast, these effects seem to be due to the interaction with voltage-gated membrane Ca2+ channels. Therefore, the alteration of transmembrane Ca2+ fluxes does not exclude the involvement of internalization process through coated pits or caveolae, since the endocytosis mediated by these phenomena essentially needs Ca2+. In addition, the inhibitory effects are dependent on the number of positive charges of the polyamine molecules.
Costuleanu
Natalia
N
Disciplina de Biochimie, Facultatea de Medicină Stomatologică, Universitatea de Medicină şi Farmacie Gr.T. Popa Iaşi.
Foia
Liliana
L
Slătineanu
Simona Mihaela
SM
Indrei
L L
LL
Costuleanu
M
M
Petrescu
Gh
G
D000465:Algorithms; D000704:Analysis of Variance; D000804:Angiotensin II / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D000818:Animals; D001011:Aorta / Q000187:drug effects; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000502:physiology; D009119:Muscle Contraction / Q000187:drug effects* / Q000502:physiology; D009131:Muscle, Smooth, Vascular / Q000187:drug effects* / Q000502:physiology; D011073:Polyamines / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D013095:Spermidine / Q000494:pharmacology
D011073:Polyamines; D000804:Angiotensin II; D013095:Spermidine