Interesting Facts about Vitamin P - Bioflavonoids - source
THE BIOLOGICAL ACTIVITY OF A FLAVONOID (VITAMIN “P”) COMPOUND Boris Sokoloff, … ,
Walter H. Eddy, James B. Redd J Clin Invest. 1951;30(4):395-400. JCI - THE BIOLOGICAL ACTIVITY OF A FLAVONOID (VITAMIN “P”) COMPOUND.
The elaboration of a practical and reliable biological test for the estimation of vitamin "P" activity is the most urgent and important problem with which every investigator in this field is confronted. The complexity of the physiological activity of flavonoid compounds was responsible for the obstacles in finding a satisfactory solution of this problem. The attempts to induce experimental avitaminosis "P" gave contradictory observations making this test unreliable for any practical use (1-8). A method was suggested for the estimation of vitamin "P" activity by using the capillary bed in the rat-mesoappendix, with a compound topically applied. It was found, however, that most of the flavonoid compounds, except catechins, did not produce any vasoconstrictor effect (9, 10). Considerable work was done with the determination of capillary permeability by using chloroform wheals applied to the skin and simultaneous injections of trypan blue. This test pertaining rather to permeability changes than to increased capillary fragility has demonstrated a great variation in the response of experimental animals to the same flavonoid compound (11, 12). More recently it was suggested that radiation injury to the capillary wall might serve as a basis for the estimation of vitamin "P" activity. Purpura, for which ascorbic acid has proved ineffective, has been a constant feature of radiation illness. It has been shown that some flavonoid compounds exert protective action against radiation injury to the capillary system (13-18). In our present report which covers both experimental and clinical data particular attention was paid to the determination of vitamin "P" activity in the condition where increased capillary fragility rather than permeability changes were evidenced.
THE BIOLOGICAL ACTIVITY OF A FLAVONOID (VITAMIN “P”) COMPOUND Boris Sokoloff, … ,
Walter H. Eddy, James B. Redd J Clin Invest. 1951;30(4):395-400. JCI - THE BIOLOGICAL ACTIVITY OF A FLAVONOID (VITAMIN “P”) COMPOUND.
The elaboration of a practical and reliable biological test for the estimation of vitamin "P" activity is the most urgent and important problem with which every investigator in this field is confronted. The complexity of the physiological activity of flavonoid compounds was responsible for the obstacles in finding a satisfactory solution of this problem. The attempts to induce experimental avitaminosis "P" gave contradictory observations making this test unreliable for any practical use (1-8). A method was suggested for the estimation of vitamin "P" activity by using the capillary bed in the rat-mesoappendix, with a compound topically applied. It was found, however, that most of the flavonoid compounds, except catechins, did not produce any vasoconstrictor effect (9, 10). Considerable work was done with the determination of capillary permeability by using chloroform wheals applied to the skin and simultaneous injections of trypan blue. This test pertaining rather to permeability changes than to increased capillary fragility has demonstrated a great variation in the response of experimental animals to the same flavonoid compound (11, 12). More recently it was suggested that radiation injury to the capillary wall might serve as a basis for the estimation of vitamin "P" activity. Purpura, for which ascorbic acid has proved ineffective, has been a constant feature of radiation illness. It has been shown that some flavonoid compounds exert protective action against radiation injury to the capillary system (13-18). In our present report which covers both experimental and clinical data particular attention was paid to the determination of vitamin "P" activity in the condition where increased capillary fragility rather than permeability changes were evidenced.
