Kinetics of the structure of neurites in mollusk brain after its dissociation

Using phase microscopy the behaviour of living neurons directly after their enzymatic isolation from ganglia of Clione limacina and Lymnaea stagnalis was studied. Apart from single-processed unipolar neurons, numerous dipolar and unipolar ones were found in mollusc which does not conform to neuron classification generally adopted. Disrupted neurons were seen to shorten gradually in Ringer solution and -1640 medium at the rate of 0.84-0.27 mm min. Serial photomicrography revealed that the process has two stages. Neurite retraction is interrupted by the expansion stage (extrusion and urgent regeneration). Duration of retraction and extrusion stages made 22.7-3.3 and 6.6-9.1 min respectively. Retraction speed was 24-0.5 mm/min while that of extrusion was 2.8-0.4 mm/min. different processes of the same neuron contract asynchronously. Process invagination leads to its rounding. Thus the cell acquires most thermodynamically stable from which is arranged to prompt its survival. Spherical neurons lacking processes migrate and demonstrate capacity of regeneration. As the conditions somehow resembling the experimental ones (high proteolytic activity of the medium and process loss in part of neurons) arise in cerebral trauma nidus of it is suggested that viable neuron behaviour is alike in this situation.