[Beta-adrenoreceptors in the muscular tissue of Anodonta cygnea].
The beta-adrenoceptors in the muscular tissue of Anodonta cygnea have been studied for the first time with the use of antagonist [125I] iodocyanopindolol. The tissue membrane had only one class of binding sites with Kd 2.9 +/- 0.02 pM and the maximal number of binding sites (Bmax) 110 +/- 2.4 fmoles/mg of protein. The potency of beta-agonists and antagonists for displacing [125I] iodocyanopindolol for its beta-AR complexes was the following: isoproterenol greater than adrenaline greater than noradrenaline-propranolol greater than serotonin much greater than dopamine greater than phentolamine. The GTP negative regulation of beta-AR affinity has been found. The data obtained show that the beta-AR are functionally coupled with GTP-binding protein which were similar to GTP-proteins of vertebrates.
Kuznetsova
L A
LA
Soltitskaia
L P
LP
D000818:Animals; D001667:Binding, Competitive; D020120:Iodocyanopindolol; D007700:Kinetics; D008024:Ligands; D008566:Membranes / Q000378:metabolism; D008974:Mollusca / Q000378:metabolism*; D009132:Muscles / Q000378:metabolism*; D010869:Pindolol / Q000031:analogs & derivatives; D011943:Receptors, Adrenergic, beta / Q000378:metabolism*
D008024:Ligands; D011943:Receptors, Adrenergic, beta; D020120:Iodocyanopindolol; D010869:Pindolol
Beta-adrenoretseptory myshechnoĭ tkani bezzubki.