N-Methyltyramine (NMT) a promising new stimulant
by Anthony Roberts
I’m always interested in new stimulants, and especially ones that I’m vaguely familiar with already – I suspect much of the same literature that lead to the arrival of this stuff on the nutritional market can likely be found on my own book shelf (some of that literature led to an interesting six and a half months for me, when I was in New Zealand).
Instead of burdening you with too many details, I’m just going to publish some of the studies that have been done on this particular ingredient, and let you make your own decisions. It’s derived from numerous DSHEA-compliant sources, at least one of which will be very familiar to most of my readers as bitter orange (typically cited on nutritional labels as the source for either synephrine or octopamine).
Personally, I think this ingredient looks really promising both from a stimulant and potential fat loss perspective. However, the true test of a stimulant is very subjective and dependent on how it makes you “feel” both during and after its use…and since it’s already on the market, and looks very good, I’m probably going to give it a try:
Stimulatory effect of N-methyltyramine, a congener of beer, on pancreatic secretion in conscious rats
Tsutsumi E, Kanai S, Ohta M, Suwa Y, Miyasaka K.
SourceResearch Center, Suntory Limited, 1-1-1 Wakayamadai, Shimamoto-cho, Mishima-gun, Osaka 618-8503, Japan. Eri_Tsutsumi@skal.suntory.co.jp
Abstract
BACKGROUND:
Alcoholic beverages stimulate gastric acid secretion and increase the appetite. Although ingested ethanol stimulates pancreatic secretion, alcoholic beverages contain several congeners. N-methyltyramine (NMT) was isolated from beer as a factor in stimulating gastric acid secretion. In this study, we examined NMT to determine whether the congener stimulated pancreatic secretion in conscious rats.
METHODS:
Cannulae were inserted into male Wistar rats to separately drain bile and pancreatic secretions: 2 duodenal cannulae, a gastric cannula, and an external jugular vein cannula. The rats were placed in modified Bollman-type restraint cages. After a 4-day recovery period, experiments were conducted on unanesthetized rats. Different concentrations of NMT (5, 25, and 50 microg/kg) solutions were infused into the stomach. To examine the mechanism, the effects of the proton pump inhibitor, cholecystokinin (CCK-BR) antagonist (YM022), CCK-AR antagonist (CR1505), and atropine were administered prior to the NMT (25 microg/kg) infusion. The effect of intravenous infusion of NMT (7.5 microg/kg) was then determined. Moreover, dispersed acini were prepared, and the effect of different concentrations of NMT on amylase release was determined.
RESULTS:
Intragastric administration of NMT significantly increased pancreatic exocrine secretion in a dose-dependent manner. Atropine eliminated the stimulatory effect of NMT, but the infusion of the proton pump inhibitor, YM022, and CR1505 did not. Intravenous infusion of NMT did not affect pancreatic secretion, and NMT did not stimulate amylase release in vitro.
CONCLUSIONS:N-methyltyramine stimulates pancreatic secretion via the cholinergic gastro-pancreatic reflex. The NMT content in beer was 2 mg/l, so that if a person weighing 60 kg consumes a 750 ml of beer, 25 microg/kg NMT will be ingested. Therefore, the stimulatory effect of beer on pancreatic secretion was produced not only by ethanol but also by the congener, NMT.
Certification of standard reference materials containing bitter orange
Sander LC, Putzbach K, Nelson BC, Rimmer CA, Bedner M, Thomas JB, Porter BJ, Wood LJ, Schantz MM, Murphy KE, Sharpless KE, Wise SA, Yen JH, Siitonen PH, Evans RL, Nguyen Pho A, Roman MC, Betz JM.Source: National Institute of Standards and Technology, Chemical Science and Technology Laboratory, 100 Bureau Drive, MS 8392, Gaithersburg, MD 20899-8392, USA. lane.sander@nist.gov
Abstract
A suite of three dietary supplement standard reference materials (SRMs) containing bitter orange has been developed, and the levels of five alkaloids and caffeine have been measured by multiple analytical methods. Synephrine, octopamine, tyramine, N-methyltyramine, hordenine, total alkaloids, and caffeine were determined by as many as six analytical methods, with measurements performed at the National Institute of Standards and Technology and at two collaborating laboratories. The methods offer substantial independence, with two types of extractions, two separation methods, and four detection methods. Excellent agreement was obtained among the measurements, with data reproducibility for most methods and analytes better than 5% relative standard deviation. The bitter-orange-containing dietary supplement SRMs are intended primarily for use as measurement controls and for use in the development and validation of analytical methods.
Antagonistic effect of N-methyltyramine on alpha2-adrenoceptor in mice.
Koda H, Yokoo Y, Matsumoto N, Suwa Y, Fukazawa H, Ishida H, Tsuji K, Nukaya H, Kuriyama K.
Source: Products Safety & Alcohol Science Laboratory, Suntory Limited, Mishima-gun, Osaka, Japan.
AbstractWe examined the effect of N-methyltyramine (NMT) on alpha2-adrenoceptor. NMT (10(-8)-10(-3) M) inhibited the binding of [3H]p-aminoclonidine to alpha2-adrenoceptor dose-dependently. However, the IC50 value for NMT (5.53 x 10(-6) M) was higher than that for RX821002, an alpha2-adrenoceptor antagonist (1.07 x 10(-8) M). RX821002 (5 mg/kg, i.p.) inhibited hypermotility induced by scopolamine (8 mg/kg, s.c.) in male ddY mice. NMT (20 or 100 mg/kg, i.p.) was found to have a dose-dependent inhibitory effect similar to that of RX821002. These findings indicate that NMT has the properties of an alpha2-adrenoceptor antagonist. However, the affinity of NMT for alpha2-adrenoceptor is weaker than that of RX821002.
COMMENTS