Lymphocyte beta-adrenergic receptor density of patients with recurrent affective illness

The binding characteristics of (-)3-[125I]iodocyanopindolol, a high specific activity antagonist for the lymphocyte beta-adrenoceptor, were determined in a group of euthymic lithium-treated patients and controls. There was a statistically significant reduction (less than 20%) in the density of beta-adrenoceptors in a group of 56 lithium-treated patients. Division of this group of patients into the unipolar and bipolar distinction indicated that the abnormality was based mainly in the bipolar group of patients. The unipolar patients with an endogenous form of the illness also showed this abnormality. Reduced beta-adrenoceptor density may be associated with endogenous affective illness. However, the results must be interpreted with caution since lymphocyte fractions prepared for beta-adrenoceptor assays can be contaminated with platelets and since platelets have been reported to have beta-receptors then a proportion of the total binding could be associated with platelet beta-adrenoceptors rather than with lymphocyte beta-adrenoceptors.

Related Concept Videos

G-protein Coupled Receptors01:21

G-protein Coupled Receptors

G-protein coupled receptors are ligand binding receptors that indirectly affect changes in the cell. The actual receptor is a single polypeptide that transverses the cell membrane seven times creating intracellular and extracellular loops. The extracellular loops create a ligand specific pocket which binds to neurotransmitters or hormones. The intracellular loops holds onto the G-protein.
Adrenergic Receptors (Adrenoceptors): Classification01:27

Adrenergic Receptors (Adrenoceptors): Classification

Adrenergic receptors, or adrenoceptors, respond to the autonomic neurotransmitter noradrenaline and other endogenous catecholamine agonists. They are classified into two main families, α and β, based on their pharmacological response and are further subdivided depending on their location, elicited response, and affinity to specific agonists or antagonists.
α-Adrenoceptors
α-Adrenoceptors are classified into two main subtypes: α1 and α2. The α1 adrenoceptors, which are found on postsynaptic...
Adrenergic Receptors: ɑ Subtype01:31

Adrenergic Receptors: ɑ Subtype

Adrenoceptors are classified into α and ꞵ classes based on their potencies to catecholamine agonists. α-adrenoceptors show the following order of catecholamine potency:
Adrenaline ≥ Noradrenaline >> Isoprenaline
α-adrenoceptors are further divided into α1 and α2-adrenoceptors.
α1-Adrenoceptors: These receptors are located postsynaptically on the effector organs and cause constriction of smooth muscle mediated by activation of phospholipase C—inositol-1,4,5-trisphosphate...
Adrenergic Receptors: β Subtype01:26

Adrenergic Receptors: β Subtype

β-adrenoceptors have varied sensitivities towards adrenaline, noradrenaline, and isoprenaline. The order of agonist potency is as follows:
Isoprenaline > Adrenaline > Noradrenaline
Neurotransmitter binding to these receptors causes activation of adenylyl cyclase resulting in increased concentrations of cAMP and modulation of calcium ion channels within the cell. They are further classified into β1, β2, and β3 subtypes.
β1-adrenoceptors: β1-adrenoceptors have equal affinities for...
Adrenergic Antagonists: Pharmacological Actions of β-Receptor Blockers01:27

Adrenergic Antagonists: Pharmacological Actions of β-Receptor Blockers

β-receptor blockers significantly impact the cardiovascular system by counteracting catecholamine-induced sympathetic responses. These medications decrease heart rate, contractility, and cardiac output, potentially leading to cardiac depression, life-threatening bradycardia, and death. Therapeutically, β-blockers function as mild antihypertensives and are utilized in treating angina pectoris and cardiac arrhythmias. However, nonselective β-blockers inhibit β2-receptors in bronchial smooth...
Adrenergic Antagonists: ɑ and β-Receptor Blockers01:31

Adrenergic Antagonists: ɑ and β-Receptor Blockers

Third-generation β-blockers, such as labetalol and carvedilol, represent a significant advancement in managing cardiovascular conditions. Unlike conventional β-blockers, which can induce peripheral vasoconstriction, third-generation drugs block α1 adrenoceptors. This promotes vasodilation through several mechanisms, such as increased nitric oxide production, inhibition of calcium ion entry, opening of potassium ion channels, and antioxidant action. Labetalol, for instance, is clinically...