Abstract
1) D.H.Q. is water soluble. It shows very little toxicity when used on mice and rabbits. 2) D.H.Q. causes a transitory fall in the blood pressure of rabbits. On the isolated hearts of frogs, it produces a slight acceleration in low concentrations and a diastolic arrest in high concentrations. No remarkable action is observed in the auricular vessels of rabbits or in the vessels of frog's hind legs.3) D.H.Q. inhibits, the movement of the isolated intestines of rabbits and guinea pigs. 4) D.H.Q. facilitates the action of adrenaline on the peripheral vessels and intestines. 5) D.H.Q. has a slight antihistaminic and antiacetylcholinic. action on the isolated intestines of guinea pigs. 6) D.H.Q. restrains an increase in capillary permeability which has been attributed to hyaluronidase or Menkin factors. In mice, it inhibits a pulmonary bleeding, which is due to low atmosphere. 7) In many respects, the actions of D.H.Q. coincide with those of rutin and quercetin.
