Terbutaline Sulfate (Terbutaline hemisulfate) is a selective beta-2 adrenergic agonist used as a bronchodilator and tocolytic.

β2-adrenoceptor:53 nM

Terbutaline acts on the β2 receptors in the bronchial, vascular, and uterine smooth muscles, stimulating them. It also exerts an effect on uterine smooth muscles by inhibiting contractions.

In all BChE variants, Terbutaline exhibits reversible competitive inhibition, with dissociation constants (Kd) of 0.18 mM for UU, 0.31 mM for FF, and 3.3 mM for AA homozygotes. Additionally, Terbutaline facilitates bronchodilation by selectively targeting β2-adrenergic receptors.

Immunoprecipitation-HDAC assays: The lysate of Jurkat cells is incubated for 1 hour on ice and cleared by centrifugation at 12,000 g for 10 minutes at 4 °C. Supernatants are precleared with 30 μL of 50% protein G-Sepharose slurry for 1 hour at 4 °C. Beads are pelleted by centrifugation and supernatants are incubated for 1 hour at 4 °C with 10 μg of IgG fraction from anti-HDAC1 or HDAC3 polyclonal antisera (preincubated 2 hours at room temperature with either the homologous or heterologous immunizing peptide). Both antisera are raised in rabbits against the carboxylterminal peptide of HDAC1 and HDAC3 by using synthetic peptides coupled to keyhole limpet hemocyanin. 30 μL of 50% protein G-Sepharose slurry is added for 1 hour at 4 °C. Immune complexes are pelleted by centrifugation and washed three times with 1 mL of lysis buffer. Beads are resuspended in 200 μL of HDAC buffer (20 mM Tris-HCl, pH 8.0/150 mM NaCl/10% glycerol), and the HDAC assay is performed with an 3H-acetylated peptide corresponding to amino acids 1-24 of histone H4. Released [3H]acetic acid is quantified by scintillation counting. For inhibitions studies, the immunoprecipitated complexes are preincubated with the different concentrations of Vorinostat for 30 minutes at 4 °C.