Ouabain

``In addition to the classical mechanism of action of ouabain, a small number of reports spanning the last 30–40 years[update] have observed that low (i.e., subnanomolar) concentrations of ouabain may sometimes stimulate the Na-K-ATPase. e.g., [2] This stimulatory effect does not appear to be mimicked by digoxin. [3] The mechanism of the stimulatory effect and its relevance to cell function is not understood.''

``Ouabain isolated from plants is widely used by scientists in in vitro studies to specifically block the sodium pump (Na-K-ATPase). In many non rodent species, low concentrations of this substance (i.e., in the subnanomolar range) may stimulate the Na-K-ATPase. The mechanism of the stimulatory effect is not understood and remains controversial. Further, the issue in rodents is more complicated because there are different isoforms of the Na-K-ATPase - some of which are very sensitive to ouabain while others are not.''

Taken from Wikipedia.

According to Ling this substance is useful to disprove the Na pump, and support his Association-Induction Hypothesis.

40 years and not understood.

I guess these problems are like math ones, which can last one hundred years (Poincaré Conjecture; now Perelman-Hamilton Theorem).

I guess that is why Dr. Ling has not given up yet, and now he has an ally; Prof. Pollack.