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The Chemistry and Biology of Nerve Growth Factor

  • Isaac Schenkein

Abstract

The “field” of nerve growth factor (NGF) has developed out of a series of investigations performed some 20 years ago by Bueker.(1–3) His experiments, done within the framework of the “center-periphery” problem, dealt with magnitude of peripheral innervation and its causal relationship to the relative size of the “center,” whence the innervating neurons had their origin.(4–10) Prior to Bueker’s unorthodox procedures, most investigators had used implantation or ablation techniques in order to produce the desired increases or decreases of peripheral fields. Bueker departed from these, implanting tumor masses in the body wall of the study object (the chick embryo) instead of the usual homologous or heterologous structures. The importance of the limb periphery as a factor essential for the differentiation of the lateral motor column in the limb segments of the spinal chord was known, as was the fact that the “stimulus,” i.e., altered size of periphery, was not species-specific.(10) Successful implantation of tumor masses (sarcoma 180) in lieu of the hind limb periphery quickly revealed important deviations from the previously observed relationships between size of periphery and development of center.(1–3) Bueker observed that:
  1. 1.

    The tumor became “innervated” by the peripheral nerves which normally form the lumbosacral plexus.

     
  2. 2.

    There was marked hypertrophy and hyperplasia of the spinal ganglia on the experimental side, although the periphery (i.e., the tumor mass) at the time of observation was decidedly smaller than the contralateral control side.

     
  3. 3.

    The lateral motor neurons of the experimental side were significantly smaller than those of the other side.

     
  4. 4.

    The tumor maintained its cellular autonomy.

     
  5. 5.

    Successful implants of rhabdo-myosarcomas did not produce these effects, an observation which was later extended by Bueker’s survey of mouse neoplasias, which showed that only certain sarcomas were effective, all carcinomas investigated being negative.(11–13)

     

Keywords

Nerve Growth Factor Chick Embryo Snake Venom Sympathetic Ganglion Spinal Ganglion 
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Copyright information

© Plenum Press, New York 1971

Authors and Affiliations

  • Isaac Schenkein
    • 1
  1. 1.Irvington House Institute Department of MedicineNew York University School of MedicineNew YorkUSA

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