| Popis: |
1. 1. Laboratory bred specimens of Lymnaea stagnalis have an anoxic tolerance of about 40 hr at 20°C. The physiological significance is discussed. 2. 2. Although the haemolymph amounts to 45% of the total body wt, data on anaerobic end products, determined separately in tissues and haemolymph, are lacking up to now. Therefore, both components were examined after various periods of anoxia. 3. 3. After 48 hr carbohydrates in the tissues are decreased to 30% of the initial content, both in living and dead snails. 4. 4. During 24 hr of anoxia, d -lactate and succinate increase markedly in tissues and haemolymph. Haemolymph levels, however, are about 4 times higher, indicating that active transport to this compartment is involved. 5. 5. Haemolymph calcium increases almost linearly during this period, due to buffering of acid end products by dissolution of calcium carbonate. 6. 6. Haemolymph samples allow a rapid and accurate check for anaerobic metabolism. |
