Acetylcholine (ACh) is a neurotransmitter a chemical messenger that plays a crucial role in transmitting signals in both the central and peripheral nervous systems. Biosynthesis of acetylcholine Location Synthesized in the cytoplasm of cholinergic neurons, particularly at nerve terminals. Precursors Choline: Obtained from diet and recycled ACh. Acetyl-CoA: Formed in mitochondria from pyruvate (product of … Read more
Loratadine is a second-generation, non-sedating H₁-antihistamine commonly used to manage allergic rhinitis, urticaria, and seasonal allergic reactions. It features a tricyclic structure that enhances peripheral selectivity and reduces central nervous system penetration, resulting in minimal sedation. It works by selectively blocking peripheral H₁ receptors, providing long-lasting relief from histamine-induced symptoms such as sneezing, itching, and … Read more
Cetirizine is a second-generation H₁-antihistamine derived from hydroxyzine, widely used for managing allergic rhinitis, chronic urticaria, and seasonal allergies. Its structure includes a piperazine ring substituted with a carboxylic acid group and an aromatic ring, contributing to its peripheral selectivity. By blocking H₁ receptors without significant CNS penetration, it effectively relieves histamine-mediated symptoms with minimal … Read more
Astemizole is a second-generation H₁-antihistamine known for its non-sedating action due to limited blood-brain barrier penetration. Structurally, it features a benzoxazole ring fused to a piperazine moiety, contributing to its high receptor selectivity. It effectively treats allergic rhinitis, urticaria, and chronic idiopathic urticaria by blocking H₁ receptors and exhibiting mild anti-inflammatory properties without significant central … Read more
Metoprolol is a selective beta-1 adrenergic receptor blocker (β1-blocker) used primarily to manage cardiovascular conditions. It reduces the effects of adrenaline on the heart, leading to decreased heart rate, cardiac output, and blood pressure. Chemical Structure & Formula: Comprises an aromatic ring joined to an oxypropanolamine chain and is typically used as a racemic mixture … Read more
General Introduction to Rauwolfia: Rauwolfia alkaloids are indole alkaloids known primarily for their sedative and antihypertensive effects. They have been used extensively in traditional medicine for treating hypertension and mental disorders. Synonyms of Rauwolfia: Common Name: Indian snakeroot alkaloids Scientific Name: Rauwolfia serpentina alkaloids Other Names: Reserpine, Ajmaline, Serpentine alkaloids Biological Source: Plant: Extracted from … Read more
General Introduction to Vinca: Vinca alkaloids are a group of dimeric indole alkaloids highly regarded for their anticancer properties. Initially extracted from the Madagascar periwinkle plant, they are used to treat various cancers by inhibiting mitotic cell division. Synonyms: Common Name: Periwinkle alkaloids Scientific Name: Catharanthus roseus alkaloids Other Names: Vincristine, Vinblastine, Catharanthus alkaloids Biological … Read more
Introduction to Alkaloids: Naturally occurring nitrogenous compounds found in plants. Introduction to Alkaloids: Known for diverse pharmacological actions like analgesic and antimalarial effects. Alkaloids are naturally occurring, nitrogen-containing compounds produced primarily by plants (though some are produced by fungi, bacteria, and animals). They often have a strong physiological effect on humans and animals. The nitrogen … Read more
Cholinergic neurotransmitters refer specifically to acetylcholine (ACh), a key chemical messenger used by certain neurons to communicate with each other or with muscle cells. These neurons are called cholinergic neurons because they release acetylcholine as their primary neurotransmitter. Function and Importance of Cholinergic Neurotransmitters Acetylcholine is involved in various physiological functions depending on where in … Read more
Labetalol is a dual-action adrenergic antagonist used primarily as an antihypertensive agent. It blocks both α1-adrenergic receptors and β-adrenergic receptors (non-selective β-blocker with selective α1-blocking activity). Chemical Structure & Formula: Unique among beta blockers, it contains dual-acting structural features (aromatic rings and a secondary amine) that allow it to block both beta and α₁ receptors. … Read more
