Distribution and properties of cardiac and pulmonary β-adrenergic receptors in corn snakes (Pantherophis guttatus) and Boa constrictor (Boa constrictor)

Publication date: Available online 28 March 2019Source: Comparative Biochemistry and Physiology Part A: Molecular & Integrative PhysiologyAuthor(s): Getu Abraham, Sandra Hoffmann, Ina Hochheim, Michael PeesAbstractThe aim of the present study was to characterize β-adrenergic receptors in the snake heart and lung of corn and Boa constrictor snakes. The β-adrenergic receptor binding sites were studied in purified heart and lung membranes using the specific β-adrenergic receptor antagonist [125J]-iodocyanopindolol (ICYP) and subtypes using selective β1-adrenergic receptor antagonist CGP-20712A and selective β2-adrenergic receptor antagonist ICI-118.551. A saturable and specific β-adrenergic receptor binding site was detected in cardiac membranes with maximal receptor density (Bmax) of 43.99 ± 3.86 fmol/mg protein (corn snake) and 58.07 ± 2.88 fmol/mg protein (Boa constrictor) as well as KD of 24.21 ± 7.38 pM (corn snake) and 21.48 ± 3.85 pM (Boa constrictor) and in lung membranes (Bmax fmol/mg protein: 55.95 ± 16.28 (corn snake) and 107.00 ± 14.21 (Boa constrictor); KD pM: 71.25 ± 21.92 (corn snake) and 55.04 ± 18.68 (Boa constrictor)). Competition-binding studies showed β-adrenergic receptors with low affinities to the β2-selective adrenergic receptor antagonist and high affinity binding to β1-selective adrenergic receptor antagonist in both heart and lung tissues of both snake species, suggesting the presence of high population ...
Source: Comparative Biochemistry and Physiology Part A: Molecular and Integrative Physiology - Category: Biochemistry Source Type: research