The neurophysin-vasopressin-like system in migratory locust embryos. Immunohistological and radioimmunological studies.
Using immunohistology and radioimmunoassay (RIA), we detected an early synthesis of the neurosecretory product related to vasopressin-neurophysin in the central nervous system of locust embryos. Both techniques gave similar results. By means of immunohistology vasopressin (VP)-like and neurophysin (NP)-like substances can be simultaneously detected as early as stage 10, i.e. 3 days before hatching. Immunofluorescent reactions are visible not only at the level of 2 suboesophageal pericarya but also in fibers and terminal arborizations running in the ventral nerve cord. These results are confirmed by RIAS at stage 10. The VP-like substance could be dosed in the same structures of the central nervous system as where it is normally found in adult locusts. The amounts in the embryos are fairly comparable to those in the adult given the different sizes of their respective nervous system. However, RIAS detected the VP-like neuropeptide in the brain as early as stage 9, i.e. 1 day earlier than with the immunohistological technique.
Romeuf
M
M
Laboratoire de Neuroendocrinologie, UA 1138 CNRS, University of Bordeaux I, 33405 Talence Cedex, France.
Proux
J
J
Remy
C
C