Alkaloidal drugs

Clinical signs and symptoms of toxicity are related to the overstimulation of muscarinic, nicotinic, and central nervous system receptors in the nervous system. Muscarinic receptors are those activated by the alkaloid drug muscarine. These receptors are under the control of the parasympathetic nervous system, and their hyperactivity results in respiratory and gastrointestinal dysfunction, incontinence, salivation, bradycardia, miosis, and sweating. Nicotinic receptors are those activated by nicotine. Hyperactivity of these receptors results in muscle fasciculations even greater stimulation results in blockade and muscle paralysis (Lefkowitz et al. 1996 Tafliri and Roberts 1987). Hyperactivity of central nervous system receptors results in the frank neurological signs of confusion, ataxia, dizziness, incoordination, and slurred speech, which are manifestations of acute intoxication. Muscarine and nicotine are not... 

Popik P, Glick SD. (1996). Ibogaine, a putatively anti-addictive alkaloid. Drugs of the Future. 21(11) 1109-15. 

The addition of organic modifiers may lead to either an increase or a decrease in retention. Moreover, the effects can differ considerably for different solutes, as is illustrated in figure 3.26 for some basic alkaloid drugs using unmodified alumina as the ion-exchange material. 

Figure 3.26 Variation of the retention of alkaloid drugs in I EC with the concentration of various organic modifiers in the mobile phase. Conditions citric acid and trimethylammonium hydroxide Figures (a) and (b) 0.01 M, pH = 6 Figure (c) (see opposite page) 0.002 M, pH = 6. Column Spherisorb A 10 Y (alumina). Solutes cocaine ( ), dihydromorphine ( ), morphine ( ), dihydrocodeine (A), ephedrine (o) and brucine (x). Figure taken from ref. [373]. Reprinted with permission.

Explain how the alkaloid drug colchicine, which binds tightly to tubulin dimers, blocks mitosis. 

LC-MS/MS Approaches to the Identification/Structural Elucidation of Alkaloid Drug Metabolites... 

To avoid the expensive use of deuterated solvents for H/D exchange experiments, Tolonen et al. [21] have described the postcolumn infusion of D2O to facilitate the LC-MS detection and identification of labile protons in a column eluant. Whilst acknowledging the potential limitations with respect to a reduced level of exchange, and hence sensitivity, compared to the use of deuterated mobile-phase solvents, they optimized the column effluent flow rate (via a splitting connector) with the infused D2O flow rate to enable the very useful determination of up to four labile protons. The method was exemplified by the differentiation of hydroxylated metabolites of the alkaloidal drugs imipramine and omeprazole (Figure 13.5) from the N-oxide and sulfone metabolites, respectively [21]. This was a differentiation that could not be achieved by high-resolution mass measurements. 

Phenyl-polydimethyl siloxane OV-3, SE-52 350 Fatty acid methyl esters, alkaloids, drugs, halogenated compounds... 

Interestingly, scientists think that many of the alkaloid "drugs" in frog skin come from the bug meals they eat—spiders and other arthropods in particular. 

Alkaloid drugs with medium to high alkaloid contents ( 1%)... 

The principal alkaloids of the most common alkaloid drugs can be identified. 

The chromatograms of the specific alkaloid drugs are reproduced according to their alkaloid types (Fig. 1-30). 

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