Hypotensive effect of gamma-glutamylmethylamide in spontaneously hypertensive rats.

The effect of gamma-glutamylmethylamide(GMA), one of the components of green tea extract, on the blood pressure in spontaneously hypertensive rats (SHR) was investigated. The effect of glutamic acid and r-glutamylethylamide (theanine), which is structurally similar to GMA, was also examined. When SHR were injected with glutamic acid (2000mg/kg), the blood pressure was not altered. The same dose of theanine decreased it significantly. GMA administration to SHR reduced the blood pressure significantly, and its degree of hypotensive action was more effective than that by theanine administration.