Effect of Irradiated Ergosterol on Mammalian Thrombocyte Counts. ∗

Abstract

The suggestion for this work was found in the observations of F. D. Gunn, 1 who found that by exposing young rabbits to radiations from the mercury vapor lamp, a distinct increase in the number of thrombocytes was obtained in one week. Brougher 2 had demonstrated that large doses of cod liver oil administered to dogs with an experimental obstructive jaundice caused a return to normal of the coagulation time, which had been prolonged. Moise and Sooy 3 showed a rise in the thrombocyte count in thrombocytopenic purpura in human beings following irradiation with ultra violet rays over a period of 3 weeks.

The question arose in our minds as to whether or not irradiated ergosterol would produce a similar rise in thrombocytes. We did not concern ourselves with the coagulation time at the beginning of these experiments.

We chose rats, since Laurens and Sooy 4 had described a simple method for thrombocyte counts in these animals and charted what they found to be the normal counts. Five rats, male and female, of unknown age, were selected at random, and the erythrocytes and thrombocytes were counted for several successive days until we obtained what we considered normal variations. The indirect method we used is as follows: The tail of the rat is carefully cleansed with soap and water and coated with vaseline. A small piece is snipped from the tip with vaseline coated scissors. The cut end is immediately immersed in the diluting fluid and a suspension of sufficient concentration obtained. The suspension of thrombocytes and red cells is then carefully shaken for 2 minutes and the counting chamber loaded therewith. The number of thrombocytes per cc. is determined from the ratio of reds to thrombocytes and the actual red count. Each thrombocyte count was done in duplicate, thus checking one against the other.