There are pasture grasses, such as reed canarygrass, that can produce a central nervous system disruption in grazing sheep. Chemical analyses of these plants (such as Phalaris tuberosa, P. arundinacea, and P. aquatica ) have revealed the presence of alkaloids like DMT and 5-MeO-DMT, but these compounds require intravenous administration to duplicate the toxicity symptoms. The observation of 5-MeO-NMT being present does not help explain the toxicity. How can something that is not orally active be orally active? A possible explanation is the presence of another indole with a one-carbon shorter chain. This is gramine, or 3-(N,N-dimethylaminomethyl)indole which is synthesized in the plant with an entirely different set of enzymes. Its human pharmacology is not known. A related homologue, one carbon longer, is the three-carbon chain compound 3-[3-(dimethylamino)propyl]indole, produced by the Upjohn Company. It has been studied clinically under the code name U-6056, at levels of up to 70 milligrams in 10 subjects, by i.m. injection. There were no reports of visual, auditory or tactile disturbances. Physically, there was a slight increase in blood pressure anad pulse rate. Certainly there were no psychological effects.