Bicuculline is a phthalide-isoquinoline compound that is a light-sensitive competitive antagonist of GABAA receptors. It was originally identified in 1932 in plant alkaloid extracts and has been isolated from Dicentra cucullaria, Adlumia fungosa, and several Corydalis species. Since it blocks the inhibitory action of GABA receptors, the action of bicuculline mimics epilepsy; it also causes convulsions. This property is utilized in laboratories around the world in the in vitro study of epilepsy, generally in hippocampal or cortical neurons in prepared brain slices from rodents. This compound is also routinely used to isolate glutamatergic receptor function.
Noscapine is a benzylisoquinoline alkaloid, of the phthalideisoquinoline structural subgroup, which has been isolated from numerous species of the family Papaveraceae. It lacks significant hypnotic, euphoric, or analgesic effects affording it with very low addictive potential. This agent is primarily used for its antitussive (cough-suppressing) effects.
The GABAA-rho receptor is a subclass of GABAA receptors composed entirely of rho (ρ) subunits. GABAA receptors including those of the ρ-subclass are ligand-gated ion channels responsible for mediating the effects of gamma-amino butyric acid (GABA), the major inhibitory neurotransmitter in the brain. The GABAA-ρ receptor, like other GABAA receptors, is expressed in many areas of the brain, but in contrast to other GABAA receptors, the GABAA-ρ receptor has especially high expression in the retina.
Cirazoline is a full agonist at the α1A adrenergic receptor, a partial agonist at both the α1B and α1D adrenergic receptors, and a nonselective antagonist to the α2 adrenergic receptor. It is believed that this combination of properties could make cirazoline an effective vasoconstricting agent.
The alpha-1A adrenergic receptor, also known as ADRA1A, formerly known also as the alpha-1C adrenergic receptor, is an alpha-1 adrenergic receptor, and also denotes the human gene encoding it. There is no longer a subtype α1C receptor. At one time, there was a subtype known as α1C, but it was found to be identical to the previously discovered α1A receptor subtype. To avoid confusion, the naming convention was continued with the letter D.
The alpha-1D adrenergic receptor, also known as ADRA1D, is an alpha-1 adrenergic receptor, and also denotes the human gene encoding it.
Laudanosine or N-methyltetrahydropapaverine is a recognized metabolite of atracurium and cisatracurium. Laudanosine decreases the seizure threshold, and thus it can induce seizures if present at sufficient threshold concentrations; however such concentrations are unlikely to be produced consequent to chemodegradable metabolism of clinically administered doses of cisatracurium or atracurium.
Glaucine(1,2,9,10-TetraMethoxyAporphine, Bromcholitin, Glauvent, Tusidil, Tussiglaucin) is an aporphine alkaloid found in several different plant species in the family Papaveraceae such as Glaucium flavum, Glaucium oxylobum and Corydalis yanhusuo, and in other plants like Croton lechleri in the family Euphorbiaceae.
Amidephrine, or amidefrine, is a sulfonamide α1-adrenergic receptor agonist.
Urapidil is a sympatholytic antihypertensive drug. It acts as an α1-adrenoceptor antagonist and as an 5-HT1A receptor agonist. Although an initial report suggested that urapidil was also an α2-adrenoceptor agonist, this was not substantiated in later studies that demonstrated it was devoid of agonist actions in the dog saphenous vein and the guinea-pig ileum. Unlike some other α1-adrenoceptor antagonists, urapidil does not elicit reflex tachycardia, and this may be related to its weak β1-adrenoceptor antagonist activity, as well as its effect on cardiac vagal drive. Urapidil is currently not approved by the U.S. Food and Drug Administration, but it is available in Europe.
Higenamine (norcoclaurine) is a chemical compound found in a variety of plants including Nandina domestica (fruit), Aconitum carmichaelii (root), Asarum heterotropioides, Galium divaricatum, Annona squamosa, and Nelumbo nucifera.
SR 59230A is a selective antagonist of the beta-3 adrenergic receptor, but was subsequently shown to also act at α1 adrenoceptors at high doses. It has been shown to block the hyperthermia produced by MDMA in animal studies.
(S)-Canadine, also known as (S)-tetrahydroberberine and xanthopuccine, is a benzylisoquinoline alkaloid (BIA), of the protoberberine structural subgroup, and is present in many plants from the family Papaveraceae, such as Corydalis yanhusuo and C. turtschaninovii.
Protopine is an alkaloid occurring in opium poppy, Corydalis tubers and other plants of the family papaveraceae, like Fumaria officinalis. Protopine is metabolically derived from the benzylisoquinoline alkaloid (S)-Reticuline through a progressive series of five enzymatic transformations: 1) berberine bridge enzyme to (S)-Scoulerine; 2) (S)-cheilanthifoline synthase/CYP719A25 to (S)-Cheilanthifoline; 3) (S)-stylopine synthase/CYP719A20 to (S)-Stylopine; 4) (S)-tetrahydroprotoberberine N-methyltransferase to (S)-cis-N-Methylstylopine; and ultimately, 5) N-methylstylopine hydroxylase to protopine.
Anisodine, also known as daturamine and α-hydroxyscopolamine, is an antispasmodic and anticholinergic drug used in the treatment of acute circulatory shock in China. It is a tropane alkaloid and is found naturally in plants of the family Solanaceae - notably Anisodus tanguticus (syn. Scopolia tangutica. Anisodine acts as a muscarinic acetylcholine receptor antagonist and α1-adrenergic receptor antagonist.
SKF-97,541 is a compound used in scientific research which acts primarily as a selective GABAB receptor agonist. It has sedative effects in animal studies and is widely used in research into potential treatment of various types of drug addiction.
FG-8205 (L-663,581) is an imidazobenzodiazepine derivative related to bretazenil, which acts as a partial agonist at GABAA receptors, with slight selectivity for the α1-containing subtype. In animal tests it has anxiolytic and anticonvulsant effects but with little sedation or ataxia produced.
(S)-Magnoflorine is a quaternary benzylisoquinoline alkaloid (BIA) of the aporphine structural subgroup which has been isolated from various species of the family Menispermaceae, such as Pachygone ovata,Sinomenium acutum, and Cissampelos pareira.
Domesticine is an α1D-adrenergic receptor antagonist. The compound belongs to the group of Aporphine alkaloids.
Isoquinoline alkaloids are natural products of the group of alkaloids, which are chemically derived from isoquinoline. They form the largest group among the alkaloids.
