Methscopolamine

Methscopolamine (Pamine) is a muscarinic acetylcholine receptor blocker.Methylscopolamine is an oral medication used along with other medications to treat peptic ulcers by reducing stomach acid secretion. With the advent of proton pump inhibitors and anti

Determination of phenylephrine hydrochloride, chlorpheniramine maleate, and methscopolamine nitrate in tablets or capsules by liquid chromatography with two UV absorbance detectors in series.[Pubmed:16512228]

J AOAC Int. 2006 Jan-Feb;89(1):53-7.

A procedure is presented for the simultaneous determination of phenylephrine HCI (PE), chlorpheniramine maleate (CM), and Methscopolamine nitrate in commercial tablets or capsules by liquid chromatography (LC) with 2 UV absorbance detectors in series. Reference and sample solutions are prepared in methanol. LC separations are performed on a 7.5 cm Novapak silica column. The mobile phase is prepared by mixing 930 mL methanol with 70 mL of a 0.5% aqueous solution of 1-pentanesulfonic acid, sodium salt. The injection volume is 20 microL; the flow rate is approximately 1 mL/min. Retention times are approximately 1.5 min for PE, 3 min for CM, and 6 min for Methscopolamine nitrate. One detector determines the first 2 compounds at 265 nm, but the third compound does not produce a detectable peak. The other detector set at 210 nm generates peaks for all 3 compounds, but only Methscopolamine is within the recorder range; the other 2 compounds are exceedingly off scale. If it is not feasible or desirable to arrange 2 UV absorbance detectors in series, separate determinations can be made, one for the first 2 compounds and the other for the third component of the mixture. Two commercial samples of tablets and 2 commercial samples of capsules were analyzed by the proposed method. Recovery studies were also conducted with amounts of the 3 compounds ranging from 80 to 120% of the quantities present in the sample solutions.

The muscarine antagonist methscopolamine and the NMDA antagonist AP-5 injected unilaterally into the nucleus accumbens cause mice to rotate in opposite directions.[Pubmed:8695045]

J Neural Transm Gen Sect. 1995;101(1-3):149-57.

Previously, we have reported that the NMDA antagonist AP-5, injected unilaterally into the nucleus accumbens of mice, induces ipsilateral rotation in monoaminergically intact mice, but contralateral rotation in monoamine-depleted animals. In this paper we report that the muscarine antagonist Methscopolamine, injected unilaterally into the nucleus accumbens, induced predominantly contralateral rotation in monoaminergically intact mice. In monoamine-depleted animals intra-accumbens Methscopolamine induced only a weak stimulation of rotational behaviour (not significant), but the direction of the rotation was exclusively contralateral, and the animals showed contralateral body deviation. Moreover, when these animals received additional treatment with the alpha-adrenergic agonist clonidine, which potentiates the motor effects of cholinergic antagonists in monoamine-depleted mice (Carlsson et al., 1991), a clear-cut contralateral rotation was induced. The observed behavioural effects are discussed in relation to the positive and negative feedback circuits, which link the nucleus accumbens with the cerebral cortex and thalamus. In previous papers, we have suggested that the ipsilateral rotation induced by AP-5 is mediated primarily by the positive feedback circuit, whereas the AP-5-induced contralateral rotation is due to interference with primarily the negative feedback circuit. Applying this reasoning to the rotational effects of Methscopolamine, it seems that Methscopolamine interferes primarily with the negative feedback circuit.

Reducing milk production in ewes at weaning using restricted feeding and methscopolamine bromide.[Pubmed:9250502]

J Anim Sci. 1997 Jun;75(6):1434-42.

Restricted feed (RF) and Methscopolamine bromide (MB), an anticholinergic agent reported to block growth hormone secretion, were evaluated as potential means for reducing milk production in ewes at weaning. On d 58 +/- 1 postpartum (d 0), 40 fall-lambing ewes were allotted to treatments in a 2 (RF vs full feed [FF]) x 2 (MB vs saline [SAL]) factorial arrangement according to breed, age, and number of lambs born and suckled. On d 0 at 0800, ewes were separated from lambs, injected with 40 IU of oxytocin, and machine milked 30 s later. Ewes remained separated from lambs for 3 h, and at 1100 they were milked and yields were determined. From d 0 through 6, FF ewes received a daily ration of 1.8 kg of alfalfa hay and .9 kg of corn; RF ewes received only 1.8 kg of alfalfa hay. On d 7 at 0800 and 1400, ewes were separated from lambs, milked, treated with a s.c. injection of either 96 mg of MB dissolved in 2 mL of SA or SA alone, and after 3-h separations were milked at 1100 and 1700 and yields determined. Lambs were weaned at 1400. After milking at 1700, all ewes were placed in drylot without feed or water. At 1100 on d 9, residual milk yields were collected. Milk samples were retained for compositional analysis at each collection time. The RF ewes produced less milk than FF ewes (106 vs 137.4 g; P < .01) at 1100 on d 7, but yields of MB and SA ewes were similar. At 1700 on d 7, milk yield was only 15.9 g less (74.3 vs 90.2 g; P < .10) for RF than for FF ewes, but it was 26 g less (69.2 vs 95.2 g; P < .01) for MB than for SA ewes. On d 9, there was no significant difference in yields of RF and FF ewes; however, MB ewes continued to produce less milk than SA ewes (96.6 vs 125.4 g; P < .10). No significant interactions between feeding regimen and MB treatment were found for milk yield. These data provide evidence that MB treatment of ewes is effective in reducing milk production. Furthermore, even greater reduction can be achieved when MB is combined with RF.

Methscopolamine bromide blocks hypothalamic-stimulated release of growth hormone in ewes.[Pubmed:9159285]

J Anim Sci. 1997 May;75(5):1359-62.

Twenty-five nonlactating ewes were used to test the hypothesis that Methscopolamine bromide (MB) blocks secretion of growth hormone (GH) by affecting hypothalamic rather than pituitary mechanisms. Ewes were randomly assigned to receive a s.c. injection of 96 mg of MB or 2 mL of saline at min = 0. Saline-treated ewes were assigned to receive a subsequent (at +60 min) i.v. injection of 10 microg of growth hormone-releasing hormone (GHRH) to test pituitary responsiveness or .3 mg of clonidine to test hypothalamic responsiveness. Methscopolamine bromide-treated ewes were assigned to receive a subsequent (at +60 min) i.v. injection of 10 microg of GHRH, .3 mg of clonidine, or 2 mL of saline. Jugular blood samples were collected at 10-min intervals from -120 min to +240 min, and serum concentrations of GH were quantified with a RIA. No difference was detected in serum concentrations of GH with respect to MB vs saline treatment (P = .20). Concentrations of GH increased in saline-pretreated ewes following injections of clonidine or GHRH (P < .01). Treatment of ewes with MB, however, limited the ability of clonidine-induced mechanisms to increase concentrations of GH, but did not affect pituitary responsiveness to GHRH (P < .01). These data support the hypothesis that MB inhibits hypothalamic and not pituitary mediated mechanisms that regulate the secretion of GH.