[Dynamics, following axotomy, of the A1 and A2 median protocerebral neurosecretory cells of the African locust. II. Ultrastructural study].

In the African locust after axotomy of the A1 and A2 median protocerebral neurosecretory cells (M-NSC), the decrease of the basophil neurosecretory products into the pericaryons does not result from an increase of the granulolysis but results from an inhibition of the production. The A1 and A2 neurosecretory products, stored anteriorly and posteriorly to the site of the axonal section, seem destroyed by: 1. a suspected entrance of lytic enzymes into the granule (individual granulolysis); 2. a vacuolar inclusion of small or big cytoplasmic areas rich in granules (partial or total collective granulolysis). The axons of the M-NSC, regenerated without reconnexion to the corpora cardiaca (CC), are not separated by glial elements. This glial deficiency could be at the origin of the inhibition of the neurosecretory dynamics observed in the A1 and A2 M-NSC after axotomy and regeneration without reconnexion to the CC.