TY - JOUR
T1 - Aerobic and anerobic metabolism of the crystalline lens of a poikilotherm; the toad Bufo marinus
AU - Yorio, T.
AU - Cruz, Elizabeth
AU - Bentley, P. J.
N1 - Funding Information:
Acknowledgements--This work was supported by NIH Grant No. EY 01278.
PY - 1979
Y1 - 1979
N2 - 1. 1. The O2 consumption and lactic acid production of the lens of the toad Bufo marinus was measured under various conditions. The energy consumption was very low compared to other amphibian tissues and about 20% of that previously described in the rat lens. About 80% was derived from oxidative metabolism, which is the converse of that seen in mammals. 2. 2. Cyanide abolished O2 consumption and increased lactate production 20-30 times ("Pasteur effect"). 3. 3. Under aerobic conditions about 40% of the energy requirements of the lens are related to the presence of Na in the bathing-media but this was not seen in the presence of CN. 4. 4. Oxidative metabolism was predominant in the outer cortical regions of the lens while glycolysis persisted even in the central nucleus. The energetic requirements of this region were, however, only about 10% of those in the intact lens. 5. 5. Lactate readily leaves the lens and passes into its bathing fluids, and at high rates of glycolysis this occurs more readily across the posterior surface. 6. 6. The results are discussed in relation to the unique physiological needs, structure and situation of the lens.
AB - 1. 1. The O2 consumption and lactic acid production of the lens of the toad Bufo marinus was measured under various conditions. The energy consumption was very low compared to other amphibian tissues and about 20% of that previously described in the rat lens. About 80% was derived from oxidative metabolism, which is the converse of that seen in mammals. 2. 2. Cyanide abolished O2 consumption and increased lactate production 20-30 times ("Pasteur effect"). 3. 3. Under aerobic conditions about 40% of the energy requirements of the lens are related to the presence of Na in the bathing-media but this was not seen in the presence of CN. 4. 4. Oxidative metabolism was predominant in the outer cortical regions of the lens while glycolysis persisted even in the central nucleus. The energetic requirements of this region were, however, only about 10% of those in the intact lens. 5. 5. Lactate readily leaves the lens and passes into its bathing fluids, and at high rates of glycolysis this occurs more readily across the posterior surface. 6. 6. The results are discussed in relation to the unique physiological needs, structure and situation of the lens.
UR - http://www.scopus.com/inward/record.url?scp=0018547926&partnerID=8YFLogxK
U2 - 10.1016/0305-0491(79)90295-5
DO - 10.1016/0305-0491(79)90295-5
M3 - Article
C2 - 122582
AN - SCOPUS:0018547926
SN - 0305-0491
VL - 62
SP - 123
EP - 126
JO - Comparative Biochemistry and Physiology -- Part B: Biochemistry and
JF - Comparative Biochemistry and Physiology -- Part B: Biochemistry and
IS - 2
ER -