Maintenance of Contraction of Embryonic Chick Hearts in Vitro

Abstract

In a soln. of 5/9 ml. of 72-hr. yolk of incubated egg added to 24 ml. of Tyrode''s sol., 72-hr. chick embryo hearts are kept alive and beating for at least 90 days on perforated cellophane disks in tightly-stoppered Carrel flasks. The flasks are never opened, and no further soln. is added. Practically no cell proliferation occurs and the cultured heart decreases in size with time.