| Popis: |
The distribution of neurons which express the gene for the growth-associated protein, GAP-43, in the adult carp central nervous system (CNS) was studied by in situ hybridization using newly formed RNA probes for carp GAP-43 mRNA. A great number of neurons heavily labeled by the 35S-labeled antisense probe were found in the telencephalon, diencephalon, mesencephalon, optic tectum, pontine area, medulla oblongata and spinal cord. Motoneurons of the cranial nerves, i.e., the oculomotor, trochlear, trigeminal and spinal motor nerves, also strongly expressed GAP-43 mRNA, in contrast to the low level of GAP-43 signals in the motoneurons in the adult mammalian CNS. These results suggested that synaptogenesis and continuous synaptic reorganization might normally occur in the adult carp nervous system, since GAP-43 protein is generally accepted to be essential for the dynamic growth of axonal processes which leads to synaptogenesis. In the mature skeletal muscle of the adult carp, a number of small-sized ... |
