There' class='bbc_url' title='External link' rel='nofollow external'>http://en.wikipedia.org/wiki/Uncaria_tomentosa']There are two species of Cat's Claw, Uncaria tomentosa and Uncaria guianensis, each having different properties and uses. The two are frequently confused but U. tomentosa is the more heavily researched for medicinal use and immune modulation, while U. guianensis may be more useful for osteoarthritis. U. tomentosa is further divided into two chemotypes with different properties and active compounds, a fact ignored by most manufacturers that can have significant implications on both its use as an alternative medicine and in clinical trials to prove or disprove its efficacy...→ source (external link)
U. tomentosa is used in nootropic drugs, as well as in treatment of cancer and HIV infection. It contains several alkaloids that are responsible for its medical effects, as well as tannins and various phytochemicals. The chemotype of the plant determines the dominant type of alkaloid it produces, and thus its properties in vivo. One chemotype has roots which produce mostly the pentacyclic alkaloids that are responsible for the immune-strengthening effects desired by most consumers. The second chemotype produces tetracyclic oxindole alkaloids known as rhynchophylline and isorhynchophylline which counteract the immune-strengthening actions of the pentacyclic alkaloids, reduces the speed and force of the heart's contraction, and in high doses produce ataxia, lack of coordination and sedative effects. Since U. tomentosa comes in at least these two different chemotypes, without chemical testing it is impossible to know which chemical compounds will predominate in a plant collected randomly from a natural setting.
Right. You bring up a valid point. The Cat's Claw lacking tetracyclic alkaloids will be more stimulating. Thus, if you notice sedating/inhibiting effects, you most likely are experiencing the strain with Rhyncophylline.
