Summary
Pools of motoneurons in the ventral horn of the brachial spinal cord segments 13–16, innervating muscles of an ectopic hindlimb were mapped in chicks with the use of retrograde axoplasmic transport of horseradish peroxidase (HRP).
On the third day of incubation the right wing bud of the acceptor embryo was removed and replaced by either a right or left hindlimb bud of the donor embryo. HRP was injected tnto selected muscles of the ectopic and intact hindlimbs as well as into muscles of the intact left wing between 17–21 days of incubation and after hatching. The position of labelled motoneuron pools representing individual muscles was determined. In 19–21 day old embryos and in hatched chicks the movement of the ectopic limbs was also studied.
HRP histochemistry showed that the ectopic limb muscles of dorsal and ventral embryonic muscle mass origin were innervated by motoneurons located in the lateral and medial parts of the ventral horn, respectively. This is similar to the innervation pattern of normal wing and hindlimb muscles. Depite the ordered motor nerve supply to the ectopic limbs they failed to display any co-ordinated movements characteristic of a normal hindlimb.
These observations indicate specific target affinities between pools of motoneurons in the spinal cord segments and appropriate limb muscles, even when the motoneuron pools and the limb are inappropriately matched. Nevertheless, it is evident that the ‘wing-like’ motor activation pattern of the brachial spinal cord segments is unable to initiate coordinated movements of the ectopic hindlimb.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Abercrombie M (1946) Estimation of nuclear population from microtome sections. Anat Rec 94:239–247
Bennett MR, Lindeman R, Pettigrew AG (1979) Segmental innervation of the chick forelimb following embryonic manipulation. J Embryol Exp Morph 54:141–154
Hamburger V (1975) Cell death in the development of the lateral motor column of the chick embryo. J Comp Neurol 160:535–546
Hamburger V, Hamilton H (1951) A series of normal stages in the development of the chick embryo. J Morphol 88:49–92
Hollyday M (1980) Organization of motor pools in the chick lumbar lateral motor column. J Comp Neurol 194:143–170
Hollyday M (1981) Rules of motor innervation in chick embryos with supernumerary limbs. J Comp Neurol 202:439–465
Hollyday M, Hamburger V (1976) Reduction of the naturally occurring motor neuron loss by enlargement of the periphery. J Comp Neurol 170:311–320
Hollyday M, Hamburger V, Farris JMG (1977) Localization of motor neuron pools supplying identified muscles in normal and supernumerary legs of chick embryo. Proc Natl Acad Sci USA 74:3582–3586
Horder TJ (1978) Functional adaptability and morphogenetic opportunism, the only rules for limb development? Zoon Suppl 6:181–192
Jacobson RD, Hollyday M (1982) A behavioral and electromyographic study of walking in the chick. J Neurophysiol 48:238–256
Lamb AH (1979) Ventral horn cell counts in a Xenopus with naturally occurring supernumerary hindlimbs. J Embryol Exp Morphol 49:13–16
Lance-Jones C, Landmesser L (1980a) Motoneurone projection pattern in the chick hind limb following early partial reversals of the spinal cord. J Physiol (London) 302:581–602
Lance-Jones C, Landmesser L (1980b) Motoneurone projection patterns in embryonic chick limbs following partial deletion of the spinal cord. J Physiol (London) 302:559–580
Lance-Jones C, Landmesser L (1981a) Pathway selection by chick lumbosacral motoneurons during normal development. Proc R Soc London B 214:1–18
Lance-Jones C, Landmesser L (1981b) Pathway selection by embryonic motoneurons in an experimentally altered environment. Proc R Soc London B 214:19–52
Landmesser L (1978a) The distribution of motoneurones supplying chick hindlimb muscles. J Physiol (London) 284:371–389
Landmesser L (1978b) The development of motor projection patterns in the chick hind limb J Physiol (London) 284:391–414
Mesulam MM (1978) Tetramethyl benzidine for horseradish peroxidase neurochemistry: a non-carcinogenic blue reaction-product with superior sensitivity for visualizing neural afferents and efferents. J Histochem Cytochem 26:106–117
Narayanan CH (1964) An experimental analysis of peripheral nerve pattern development in the chick. J Exp Zool 156:49–60
Pettigrew AG, Lindeman R, Bennett MR (1979) Development of the segmental innervation of the chick forelimb. J Embryol Exp Morphol 49:115–137
Romer AS (1927) The development of the thigh musculature of the chick. J Morphol 43:34–385
Romanes GJ (1951) The motor cell columns of the lumbar-sacral spinal cord of the cat. J Comp Neurol 94:79–101
Stirling RV, Summerbell D (1977) The development of functional innervation in the chick wing bud following truncations and deletions of the proximodistal axis. J Embryol Exp Morphol 41:189–207
Straznicky K (1963) Function of heterotopic spinal cord segments investigated in the chick. Acta Biol Acad Sci Hung 14:145–155
Straznicky C (1982) The innervation and the function of ectopic limbs in the chick. Neurosci Letts Suppl 10:p 463
Strazicky C, Tay D (1983) The localization of motoneuron pools innervating wing muscles in the chick. Anat Embryol 166:209–218
Sullivan GE (1962) Anatomy and embryology of the wing musculature of the domestic fowl (Gallus). Aust J Zool 10:458–518
Summerbell D, Stirling RV (1981) The innveration of dorsoventrally reversed chick wing: evidence that motor axons do not actively seek out their appropriate targets. J Embryol Exp Morphol 61:233–247
Székely G (1963) Functional specificity of spinal cord segments in the control of limb movements. J Embryol Exp Morphol 11:3–18
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Straznicky, C. The patterns of innervation and movements of ectopic hindlimb supplied by brachial spinal cord segments in the chick. Anat Embryol 167, 247–262 (1983). https://doi.org/10.1007/BF00298514
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00298514