Emetic activity

Koenig, W. A., Rahn, W., Vetter, R., Identify and quantify emetic active constituents in roast coffee, Coll. Sci. Int. Cafe, 9, 145, 1980. (CA96 121183c)... 

SEA (Leu-48-Gly) and SEB (Phe-44-Ser) mutants unable to bind major histocompatibility complex class II remain emetic but lack T-cell mitogenic effects. " A disulfide loop in SEs, which is absent in the non-enterotoxic TSST-1, may be responsible for the emetic activity of SEs but that too remains controversial. Carboxymethylation of histidines on SEA or SEB generates superantigenic molecules devoid of enter-otoxicity or skin reactivity. This chemically modified SEB also inhibits, perhaps in a competitive fashion, the... 

The alpha and beta nomenclature has been convenient to classify structures which clearly contain a dopamine like fragment. Ignoring for the moment subtypes of receptors, it seems the data have generally supported the idea that the alpha rotameric form of dopamine is more important for emetic activity and activity at DA2 receptors, while the beta rotameric form is more essential for action at the renal DA receptor. Some Important exceptions to this generalization will be presented later. 

Tyers MB, Freeman AJ. Mechanism of the anti-emetic activity of 5-HT3 receptor antagonists. Oncology 1992 49(4) 263-268. 

The existence of chirality in nature is of particular importance in numerous recognition processes, often illustrated by examples detectable by non-spectroscopic methods such as the different orange and lemon odors of R-(+)- and S-(-)-limonene, respectively (Fig. 3) [8]. As such, chiral discrimination is also of considerable consequence in the medical sciences, as often one enantiomer is pharmaceutically active whereas the other may show adverse side effects. A historic example is the anti-emetic activity of one of the enantiomers of thalidomide, while the other can cause fetal damage [9,10]. These considerations highlight the importance of chiral discrimination in the production of biologically active materials, whereas on the other hand, the design of routes to asymmetric synthesis presents an active challenge to synthetic chemists worldwide. 

Prochlorperazine is widely used for its anti-emetic activity and its effectiveness in suppressing dizziness due to labrintine disorder. Oral bioavailability is very low, due to extensive intestinal and hepatic frrstpass metabolism. Furthermore, the oral route is impractical in patients with nausea and vestibular disturbance, who have been demonstrated to have impaired gastric emptying. 

A new efficient method for the direct amidation of /-lysergic acid was used to prepare a variety of lysergamides. A pharmacological evaluation of these compounds, their di- and tetrahydro derivatives, and derivatives bearing substituents in the indole portion of the molecule showed that, in general, only 9,10-dihydrolysergamides of primary amines possess activity comparable to the potent emetic activity of the components of dihydroergotoxine. 

Pharmacology. Compounds were examined for their emetic activity by intravenous administration to mongrel dogs of either sex weighing 10-14 kg. Three to four animals were medicated at each dose, at 0.3 log dose intervals. A few of the compounds were soluble in aqueous solution but most required the use of PEG 200 or dilute lactic acid for solubilization. Animals were observed continuously for up to 60 min following medication and only the actual expulsion of gastric contents was scored as emesis.18... 

The mechanism of cannabinoid antiemetic activity is not well understood. As pointed out above, it does not seem to involve CB, or CB2. Fan has shown that anandamide and some synthetic cannabinoid agonists inhibit the activation of 5-HT3 receptors in rat nodose ganglion neurons [61]. These receptors are known to mediate emetic activity. However, we have found that HU-211 does not bind to 5-HT3 receptors (unpublished observations). Hence, although cannabinoids may act, in part at least, through this serotonin receptor, this mode of action does not account for the total activity. 

PARP-1 inhibitor with the specificity and in vivo activity to enhance chemotherapy and radiation therapy of human cancer (Calabrese et al, 2004). GR205171 has the most potent anti-emetic activity of any tachykinin NKl receptor antagonist described to date. The compound is orally active in the ferret and dog, long-lasting, and warrants further investigation as a potential broad-spectrum anti-emetic agent (Gardner et al, 1996). 

The fruit of Euonymus europaeus (the European spindle tree) and the bark of Euonymus atropurpureus (Wahoo bark) have cathartic and emetic activity, due to sesquiter-penoids and cardiac glycosides that they contain. 

Detection in nasal isolates1, % Emetic activity HLA specificity Human TCR specificity... 

Antidotes can change the chemical nature of a poison by rendering it less toxic or preventing its absorption. Formaldehyde poisoning can be treated with ammonia to promote formation of hexamethylenetetramine sodium formaldehyde sulfoxylate can convert mercuric ion to the less soluble metallic mercury and sodium bicarbonate converts ferrous iron to ferrous carbonate, which is poorly absorbed. Chemical inactivation techniques seldom are used today, however, because valuable time may be lost, whereas emetics, activated charcoal, and gastric lavage are rapid and effective. The treatment of choice for ingestion of either acids or alkalis is dilution with water or milk. Similarly, bums produced by acid or alkali on the skin should be treated with copious amounts of water. 

A patient can be induced to vomit to regurgitate ingested toxins by administering an emetic. Activated charcoal should be administered if the patient ingested caustic material. 

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