Acetoacetate, d-3-hydroxybutyrate and glucose utilization by capillaries isolated from developing rat brain

Area of Science:

• Neuroscience
• Biochemistry
• Metabolism

Background:

• Cerebral capillaries are crucial for brain energy supply.
• Understanding substrate utilization in developing brains is vital.

Purpose of the Study:

• To investigate glucose and ketone body utilization by isolated rat cerebral capillaries.
• To compare oxidative metabolism and lipid synthesis from these substrates.

Main Methods:

• Isolated cerebral capillaries from developing rats.
• Incubation with radiolabeled glucose and ketone bodies ([U-(14)C]glucose).
• Measurement of CO(2) production and incorporation into lipids and sterols.

Main Results:

• Capillaries utilized both glucose and ketone bodies for oxidative metabolism.
• CO(2) production was higher from glucose than ketone bodies, except at 5 mM.
• Ketone body utilization and lipid synthesis were concentration-dependent and comparable to glucose at low concentrations.

Conclusions:

• Developing rat cerebral capillaries rely on both glucose and ketone bodies.
• Glucose is a primary oxidative substrate, while ketone bodies contribute significantly to lipid synthesis at higher concentrations.