CALCITONIN GENE-RELATED PEPTIDE IDENTIFIES SPINAL MOTONEURONS INVITRO

Cell dissociation of E6 chick spinal cord followed by isolation of larger low‐density cells by using a discontinuous density metrizamide gradient resulted in the obtention of a motoneuron‐enriched fraction of cells. These cells were cultured in the presence of horse serum and muscle extract for a period of 8 days and examined for the presence of calcitonin gene‐related peptide. More than 90% of such cells were positive for calcitonin gene‐related peptide. When E14 spinal cord was examined, calcitonin gene‐related peptide was present only in the axons of primary sensory neurons and in the somas of motoneurons in the ventral horns. It is concluded that more than 90% of the neurons in our cultures are motoneurons. Copyright © 1990 Wiley‐Liss, Inc.