Pindolol (CAS 13523-86-9)

Pindolol acts as an antagonist for both 5-HT1A and 5-HT1B receptors, exhibiting high affinity with Ki and IC50 values of 8.9 and 6.8 nM, respectively. Furthermore, it functions as a partial agonist for the β3 adrenoceptor with a pEC50 of 5.11. As an antagonist of β1- and β2-adrenergic receptors (β1- and β2-ARs), Pindolol binds competitively with Kis of 2.6 and 4.8 nM, respectively. Additionally, it acts as a partial agonist of the β3-AR, stimulating adenylyl cyclase when expressed in human receptor-containing cell membranes. Pindolol also functions as an antagonist of the serotonin 5-HT1A receptor, inhibiting 5-HT-stimulated GTPγS binding with a Ki value of 81.1 nM. Pindolol, an aryloxypropanolamine derivative, acts as a competitive β-adrenergic receptor blocker, resulting in reduced β-adrenergic activities such as vasodilation, negative chronotropic effects, and negative inotropic effects. Additionally, it acts as a blocker of serotonin (5-HT) 1A receptors, leading to increased availability of serotonin in the brain. This elevation in serotonin levels enhances the antidepressant action of SSRIs and monoamine oxidase inhibitors. As an indole compound, it exhibits practical insolubility in water and is relatively neutral. Pindolol has been detected in various biofluids, including urine and blood, primarily located in cell membranes. Its action pathway involves the blockade of beta-1 adrenergic receptors.