The same nuclei in the
    brainstem auditory pathway that
    are first to become myelinated
    also have the  highest blood flow
    and metabolism.
3 -  Site of highest metabolic activity
  Sokoloff et al. (1977) refined the autoradiographic
method further by using carbon-14 labeled
deoxyglucose [1].  This is an analogue of glucose that
enters the brain but then is not further metabolized.  
Results of this method provide a measure of glucose
utilization that can differ from blood flow in some
circumstances.  Normally glucose uptake is greatest in
the same brain areas with the highest rate of
circulation.  Baseline values for blood flow and
deoxyglucose uptake can both be used as estimates
of metabolic rate, and these methods are now
revealing more and more the often surprising effects
of drugs and other factors that alter homeostasis in
the brain.

 Sokoloff (1981) discussing measurements of regional
glucose uptake stated, “the inferior colliculus is clearly
the most metabolically active structure in the brain”  
[2]. Figure 12 is an autoradiographic photo (from an
article by Kety 1962) that shows the high rate of blood
flow in the inferior colliculus [3].

 Using other measures of cerebral metabolism,
Rahner-Welsch et al (1995) and Zeller et al (1997)
reported the highest levels of glucose transport
proteins in the inferior colliculus of rat brains [4, 5].  
Hovda et al (1992) found the mitochondrial enzyme
cytochrome oxidase (COX) to be highest in the inferior
colliculus of developing cats, corresponding to the
finding of Chugani et al (1991) of greatest uptake of
glucose during early development [6, 7].  Gonzalez-
Lima (1997) confirmed the high levels of COX in the
inferior colliculus in the human brain, and that this
enzyme is diminished in the brains of Alzheimer
patients [8].

 Energy production in the brain supports
neurotransmission, and neurons that are involved in
the most active circuits of the brain also have the
greatest need for metabolic maintenance.  
Transcription of DNA to messenger and transfer RNA
components, then assembly of peptide subunits for
enzymes that synthesize neurotransmitters and
accomplish aerobic energy production are on-going
processes that must take place at high levels.  Kirikae
et al. (1988) demonstrated a coupling of glucose
metabolism to the production of protein and
maintenance of structural components of nerve cells.  
The rate of incorporation of the amino acid valine into
proteins was found to be highest in the inferior
colliculus, as expected from the high rate of energy
production in this auditory nucleus [9].
Full References
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References
  1. Sokoloff L, Reivich M, Kennedy C, Des Rosiers MH, Patlak CS, Pettigrew KD, Sakurada O,
    Shinohara M (1977) The [14C]deoxyglucose method for the measurement of local cerebral
    glucose utilization: theory, procedure, and normal values in the conscious and anesthetized
    albino rat. Journal of Neurochemistry 28:897-916.
  2. Sokoloff L (1981) Localization of functional activity in the central nervous system by
    measurement of glucose utilization with radioactive deoxyglucose.  Journal of Cerebral
    Blood Flow and Metabolism 1:7-36.
  3. Kety SS (1962) Regional neurochemistry and its application to brain function. In French, JD,
    ed, Frontiers in Brain Research. New York: Columbia University Press, pp 97-120.
  4. Rahner-Welsch S, Vogel J, Kuschinsky, W (1995) Regional congruence and divergence of
    glucose transporters (GLUT1) and capillaries in rat brains.  Journal of Cerebral Blood Flow
    and Metabolism 15:681-686.
  5. Zeller K, Rahner-Welsch S, Kuschinsky W (1997) Distribution of Glut1 glucose transporters
    in different brain structures compared to glucose utilization and capillary density of adult rat
    brains. Journal of Cerebral Blood Flow and Metabolism 17:204-209.
  6. Hovda DA, Chugani HT, Villablanca JR, Badie B, Sutton RL (1992) Maturation of cerebral
    oxidative metabolism in the cat: a cytochrome oxidase histochemistry study. Journal of
    Cerebral Blood Flow and Metabolism 12:1039-1048.
  7. Chugani HT, Hovda DA, Villablanca JR, Phelps ME, Xu, W-F (1991) Metabolic maturation of
    the brain: a study of local cerebral glucose utilization in the developing cat. Journal of
    Cerebral Blood Flow and Metabolism 11:35-47.
  8. Gonzalez-Lima F, Valla J, Matos-Collazo S (1997) Quantitative cytochemistry of cytochrome
    oxidase and cellular morphometry of the human inferior colliculus in control and Alzheimer's
    patients. Brain Research 752:117-126.
  9. Kirikae M, Diksic M, Yamamoto YL (1988) The transfer coefficients for L-valine and the rate
    of incorporation of L-[1-14C] valine into proteins in normal adult rat brain. Journal of
    Cerebral Blood Flow and Metabolism 8:598-605.
Deoxyglucose uptake in monkey & rat brain
Brain StructureMonkeyAlbino RatBrain System

SD 1-4SD 2-7
Inferior colliculus103197auditory
Auditory cortex79162
Vestibular nucleus66128
Medial geniculate65131auditory
Superior olivary nucleus63133auditory
Visual cortex59107
Mammillary body57121limbic
Superior colliculus5595auditory
Thalamus, lateral nucleus54116
Caudate-putamen52110subcortical motor
Cochlear nucleus51113auditory
Cerebellar nuclei45100
Sensorimotor cortex44120
Lateral geniculate3996visual
Hippocampus3979limbic
Cerebellar cortex3157
Cerebellar white matter1237

    Figure 12 -

    Blood flow and metabolism
    are not uniform throughout
    the brain.  The same nuclei
    in the brainstem auditory
    pathway that are first to
    become myelinated during
    prenatal life also have the
    highest blood flow and
    metabolism.
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Table 4
  1. Sokoloff L et al. (1977) The
    [14C]deoxyglucose method
    for the measurement of local
    cerebral glucose utilization:
    theory, procedure, and
    normal values in the
    conscious and anesthetized
    albino rat.
  2. Sokoloff L (1981)
    Localization of functional
    activity in the central nervous
    system by measurement of
    glucose utilization with
    radioactive deoxyglucose.  
  3. Kety SS (1962) Regional
    neurochemistry and its
    application to brain function.
  4. Rahner-Welsch S et al.
    (1995) Regional congruence
    and divergence of glucose
    transporters (GLUT1) and
    capillaries in rat brains.  
  5. Zeller K et al. (1997)
    Distribution of Glut1 glucose
    transporters in different
    brain structures compared
    to glucose utilization and
    capillary density of adult rat
    brains.
  6. Hovda DA et al. (1992)
    Maturation of cerebral
    oxidative metabolism in the
    cat: a cytochrome oxidase
    histochemistry study.
  7. Chugani HT et al. (1991)
    Metabolic maturation of the
    brain: a study of local
    cerebral glucose utilization
    in the developing cat.
  8. Gonzalez-Lima Fet al. (1997)
    Quantitative cytochemistry of
    cytochrome oxidase and
    cellular morphometry of the
    human inferior colliculus in
    control and Alzheimer's
    patients.
  9. Kirikae M et al. (1988) The
    transfer coefficients for L-
    valine and the rate of
    incorporation of L-[1-14C]
    valine into proteins in
    normal adult rat brain.
Table 4
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Figure 12
From Kety (1962) with permission from
Columbia University Press