Androstane and withanolides from Physalis cinerascens

Bronchodilators are critical in managing asthma, a chronic respiratory condition characterized by airway constriction due to inflammation and hyper-reactivity. Specifically, bronchodilators ease this constriction by relaxing the bronchial muscles, facilitating easier breathing.
One class of bronchodilators includes β2-adrenoceptor agonists. These agents target the β2-adrenoceptors located on bronchial smooth muscle cells. By stimulating these receptors, β2-agonists induce relaxation in these...

Prostacyclin receptor agonists are a class of therapeutic agents integral to managing pulmonary arterial hypertension (PAH). These drugs operate by mimicking the action of prostaglandin I2, or PGI2, a naturally occurring compound in the body.
These agonists bind to the IPR receptor situated on the plasma membrane of the pulmonary artery smooth muscle cells. This binding triggers a cascade of reactions known as the GS-AC-cAMP-PKA pathway. This pathway results in the relaxation of smooth muscle...

Adrenergic antagonists, or sympatholytics, inhibit adrenoceptor activation driven by catecholamines or agonists. Based on their adrenoceptor specificity, adrenergic blockers can be categorized into two primary groups: α-adrenergic blockers (α-blockers) and β-adrenergic blockers (β-blockers). α-blockers interact with α1 and α2 subtypes of α-adrenoceptors.
Nonselective α-blockers: Nonselective α-blockers contain haloalkylamine or imidazoline moieties. Phenoxybenzamine, with a haloalkylamine...

Muscarinic receptor antagonists, also known as antimuscarinic agents, are a class of bronchodilators used to treat asthma, although they are more commonly used to treat COPD. They work by inhibiting the action of acetylcholine (ACh), a neurotransmitter, on muscarinic receptors found in the airways.
Antimuscarinic agents compete with ACh for the same binding site on the muscarinic receptors. By binding to these receptors, they inhibit the downstream effects of ACh and block the parasympathetic...

Drugs that mimic the action of endogenous catecholamines like noradrenaline and adrenaline are called adrenergic agonists or sympathomimetics. Based on their mechanism of action, sympathomimetics can be classified as direct-, indirect-, or mixed-acting sympathomimetics. Direct-acting adrenergic agonists activate adrenoceptors without affecting presynaptic neurons, making them independent of neuronal catecholamine-depleting agents like reserpine and guanethidine.
These agents can be classified...

α-Adrenergic antagonists, known as α-blockers, exert their effects by inhibiting α-adrenoceptors, leading to specific physiological actions. α1-blockers and α2-blockers have distinct pharmacological actions and therapeutic applications.
α1-blockers: These drugs inhibit α1-adrenoceptors on smooth muscle cells, resulting in vasodilation. This vasodilation lowers blood pressure, making α1-blockers valuable in treating hypertension. Additionally, α1-blockers effectively address urinary obstruction...