| Abstract: | Abstract— The distribution in vivo of glucose and lactate between the complete or sub- divided retina and the blood has been evaluated in DBA and C3H mice during postnatal development. Levels in vivo of several intermediates of glucose and energy metabolism were measured by enzyme-linked fluorometric assays of freeze-dried retinae; glucose and lactate were determined in freshly-drawn plasma. DBA retinae. During the first 20 days of postnatal life, the level of glucose in the plasma rose slightly while that in the retina declined: during this period the level of lactate in the plasma rose and became nearly equal to that in the retina. Changes during development in levels of glucose and glycogen were consistent with the interpretation that the rate of utilization of glucose in vivo is enhanced during early postnatal life. C3H retinae. The levels of glucose and glycogen in vivo were abnormally high throughout the developmental period, whereas levels of lactate were normal. The rise in levels of glucose after the 15th postnatal day was not related to an increase in blood levels of glucose but rather to a decreased utilization of glucose during this period. For the first 10 postnatal days the content of glucose, lactate, ATP and P-creatine within the photoreceptor layer of C3H retinae were within normal limits. Then, biochemical changes occurred which were secondary to ultrastructural pathology in the photoreceptors. This observation suggested that glucose metabolism and energy production are not involved in the primary aetiology of the inherited disease. |
