Moguisteine

Moguisteine is a novel peripheral non-narcotic antitussive drug.

Determination of the active metabolite of moguisteine in human plasma and urine by LC-ESI-MS method and its application in pharmacokinetic study.[Pubmed:22626894]

J Chromatogr B Analyt Technol Biomed Life Sci. 2012 Jun 15;899:31-5.

In this study, a sensitive and reproducible electro-spray ionization liquid chromatography-mass spectrometry (LC-ESI-MS) method was established to determine the concentration of M1, the main active metabolite of Moguisteine in human plasma and urine. The analysis was performed on a Diamonsil(R) C(1)(8)(2) column (150 mm x 4.6 mm, 5 mum) with the mobile phase consisting of 0.1% formic acid-acetonitrile (57:43, v/v, pH=3.0) at a flow rate of 0.8 mL min(-)(1). The pseudo-molecular ions [M+H]+ (m/z 312.2 for M1 and 446.3 for glipizide) were selected as the target ions for quantification in the selected ion monitoring (SIM) mode. Plasma samples were analyzed after being processed by acidification with formic acid and protein precipitation with acetonitrile. Urine samples were appropriately diluted with blank urine for analysis. Calibration curve was ranged from 0.02 to 8 mug mL(-)(1). The extraction recovery in plasma was over 90%. Both the inter- and intra-day precision values were less than 7.5%, and the accuracy was in the range from -6.0% to 6.0%. This is the first reported LC-ESI-MS method for analyzing M1 in human plasma and urine. The method was successfully applied to the pharmacokinetic study after oral administration of single-dose and multiple-dose of Moguisteine tablets in healthy Chinese subjects.

Involvement of ATP-sensitive K(+) channels in the anti-tussive effect of moguisteine.[Pubmed:10794823]

Eur J Pharmacol. 2000 Apr 28;395(2):161-4.

The effect of glibenclamide, an ATP-sensitive K(+) channel blocker, on the anti-tussive effect of Moguisteine and of pinacidil, an ATP-sensitive K(+) channel opener in guinea pigs was studied. Pinacidil (1 and 5 mg/kg, subcutaneous (s.c.)) dose-dependently reduced the number of coughs. The anti-tussive effect of pinacidil was significantly and dose-dependently antagonized by pre-treatment with glibenclamide (3 and 10 mg/kg, i.p.). Moguisteine (1 and 5 mg/kg, s.c.) dose-dependently reduced the number of coughs. The anti-tussive effect of Moguisteine was also reduced by pre-treatment with glibenclamide, in a dose-dependent manner. However, pre-treatment with glibenclamide had no effect on the anti-tussive effects of dihydrocodeine and dextromethorphan. Glibenclamide (10 mg/kg, i.p.), by itself, had no significant effect on the number of coughs. These results suggest that pinacidil and Moguisteine may exert their anti-tussive effects through the activation of ATP-sensitive K(+) channels. Furthermore, it is possible that ATP-sensitive K(+) channels may be involved in the anti-tussive effect of peripherally acting non-narcotic anti-tussive drugs.

Effects of moguisteine on the cough reflex induced by afferent electrical stimulation of the superior laryngeal nerve in guinea pigs.[Pubmed:9874172]

Eur J Pharmacol. 1998 Dec 4;362(2-3):207-12.

The study aimed to further demonstrate the peripheral antitussive properties of Moguisteine. Firstly, the antitussive effect of Moguisteine on the cough reflex induced by inhalation of citric acid aerosol was evaluated in conscious guinea pigs. Secondly, the effects of both Moguisteine and codeine on the centrally mediated cough reflex induced by afferent electrical stimulation of the superior laryngeal nerve were investigated in anesthetized guinea pigs. Moguisteine (2.5-10 mg/kg, intravenously, i.v.) reduced the cough reflex induced by 7.5% citric acid aerosol in a dose-dependent manner, with an ED50 value of 0.55 mg/kg. Both i.v. (0.5-4 mg/kg) and intracerebroventricular (i.c.v., 5-20 microg) injection of codeine dose dependently inhibited the cough reflex induced by afferent electrical stimulation of the superior laryngeal nerve; the ED50 values were 0.91 mg/kg and 7.90 microg, respectively. The inhibitory effect of codeine (4 mg/kg i.v.) was abolished by pretreatment with naloxone (2 mg/kg intraperitoneally). In contrast to codeine, neither i.v. (4 and 20 mg/kg) nor i.c.v. (20 microg) injection of Moguisteine affected the cough reflex. These results suggest that the antitussive effect of codeine is mediated by central opioid mechanisms, whereas the antitussive effect of Moguisteine is mediated by peripheral mechanisms.

Inhaled pinacidil, an ATP-sensitive K+ channel opener, and moguisteine have potent antitussive effects in guinea pigs.[Pubmed:12120760]

Jpn J Pharmacol. 2002 Jun;89(2):171-5.

We investigated whether inhaled pinacidil and Moguisteine inhibit capsaicin-induced coughs in guinea pigs. Inhaled pinacidil (15 - 60 microg/ml), an ATP-sensitive K+ channel opener, and Moguisteine (15 - 60 microg/ml) each dose-dependently inhibited the number of capsaicin-induced coughs. The antitussive effects of pinacidil and Moguisteine were significantly antagonized by pretreatment with glibenclamide (10 mg/kg, i.p.), an ATP-sensitive K+ channel blocker. However, pretreatment with naloxone methiodide (10 mg/kg, s.c.) had no significant effect on the antitussive effects of either pinacidil or Moguisteine. On the other hand, inhaled dihydrocodeine (15 - 60 microg/ml) also dose-dependently suppressed the number of capsaicin-induced coughs. The antitussive effect of inhaled dihydrocodeine was significantly antagonized by pretreatment with naloxone methiodide (10 mg/kg, s.c.), but not by glibenclamide (10 mg/kg, i.p.). These results indicate that inhaled pinacidil and Moguisteine both attenuate capsaicin-induced coughs. Pinacidil and Moguisteine may exert their antitussive effects through the activation of ATP-sensitive K+ channels in the tracheobronchial tract. Furthermore, it is possible that ATP-sensitive K+ channels may be involved in the antitussive effects of peripherally acting non-narcotic antitussive drugs.