Three-dimensional computer-aided reconstruction of FMRFamide immunopositive neuron distribution in the ventral ganglion of the barnacle Balanus amphitrite (Cirripedia, Crustacea)

We have implemented a simple program to solve three of the problems related to 3D reconstruction (3D-Rec) of soft tissues: alignment of sections, dist ortions, and estimation of the spatial position of elements of interest ins ide the tissues. As a model, we chose the distribution of FMRFamide-like im munopositive neurons in the ventral ganglion of the barnacle Balanus amphit rite collected during different seasonal periods. Images of immunostained s ections were acquired by means of a CCD-camera-equipped microscope and a PC and the reference points were taken inside the sections. The FMRFamide-lik e immunopositive neurons detected in the barnacle ventral ganglion were gro uped into four different classes according to size, shape and staining inte nsity. More numerous FMRFamide-like immunopositive neurons were detected in the autumn-collected barnacle than in the summer counterpart. The two 3D r econstructions obtained from transverse and longitudinal ventral ganglion s ections were efficaciously compared after 90 degrees rotation of one of the m. Comparison of these two 3D-Rec suggests the presence of at least two gro ups of FMRFamide-like immunopositive neurons that are seasonally-related an d probably involved in reproduction.