Abstract:The secretion of melatonin by the pineal has been promoted as a direct monitor of adrenergic function in depressive illness. However, discrepant findings have been reported, possibly reflecting a complex adrenergic regulation of pineal output. In order to clarify the anatomical localization and relative density of β‐adrenergic receptors and their subtypes in human pineal, quantitative autoradiographic analysis was conducted of β‐adrenergic receptors in postmortem specimens using the high affinity radioligand125I‐pindolol. Dense specific binding was found throughout the gland. β1,‐adrenergic receptors were more numerous, but β2‐receptors were present in an overlapping anatomical distribution with