Relationship between weight gain and lymph flow in dog lungs.
Lung weight is a useful indicator of increases in lung extravascular volume. In addition, the lung lymph flow rate (QL) is an important factor in lung fluid balance. We have studied the weight and QL responses to elevations in capillary pressure (Pc) in intact dog lung lower left lobes. We measured lobe weight continuously. We also measured QL from small lymph vessels from the same lobes. The base-line QL was 1.7 +/- 1.5 microliter/min, and the weight was constant. After we increased Pc by 8-20 cmH2O, both weight and QL increased transiently. In most lungs the weight reached a new steady state. When we increased Pc further, weight increased continuously; however, QL reached a plateau. The continuous weight gain was due to edema. These results show that weight and QL respond similarly in nonedematous lungs; however, the weight and QL responses in edematous lungs may be different.
D000818:Animals; D001794:Blood Pressure; D002196:Capillaries / Q000502:physiology; D004285:Dogs; D004487:Edema / Q000503:physiopathology; D008168:Lung / Q000502:physiology* / Q000503:physiopathology; D008196:Lymph / Q000502:physiology*; D009929:Organ Size