THORACIC DUCT LYMPH AND LYMPHOCYTES DURING PRIMARY HYPOXIA AND REBOUND.

Abstract

Thoracic duct lymph flow and lymphocytes were first studied in 18 normal guinea pigs. Similar studies were then made on a) 25 guinea pigs placed in a decompression chamber at a simulated altitude of 14,000 ft for times ranging from 1 to 5 days, this being the period of "primary hypoxia" during which erythropoiesis is stimulated and polycythemia develops, and b) 25 guinea pigs exposed to primary hypoxia for 5 days, then kept in room air for times ranging from 1 to 5 days, this period of posthypoxic polycythemia being known as "rebound." By the end of rebound the polycythemia had almost disappeared. The flow of thoracic duct lymph increased significantly from a control level of 0.86 ± 0.21 ml/hr to 1.23 ± 0.1 ml/hr by the 5th day of primary hypoxia, and to a peak of 1.89 ± 0.23 ml/hr by the 3rd day of rebound, falling slightly to 1.56 ± 0.14 ml/hr by the 5th day of rebound, when it was still markedly above control level. The total cell content of the lymph also rose significantly, from 34.5 ± 10.3 x 106 lymphocytes/hr in the control animal to 59.1 ± 8.9 x 106 /hr on the 5th day of primary hypoxia, and to a peak of 93.8 ± 23.0 x 106 on the 3rd day of rebound.