[Ultrastructural changes in the supraoptica-neurohypophyseal system after induction of lesions in the pituitary stalk in rats].
Fine structural changes occurring in the supraoptic nucleus and the neural lobe have been studied in rats following the electrolytic lesion of the hypophysial stalk. Supraoptic neurosecretory neurones undergo a typical chromatolytic reaction. In addition, proliferating microglial cells disconnect axosomatic synapses and phagocytose degenerating neurones. Surviving neurones show signs of structural restitution 3 to 4 weeks after surgery. In the neurohypophysis degeneration of secretory nerve endings started with the disintegration of secretory vesicles 3 to 4 d postoperatively. Degenerated axon terminals were engulfed by pituicytes. Signs indicative of axonal regeneration were not observed in the neural lobe up to the end of the 4th postoperative week.
D000818:Animals; D008854:Microscopy, Electron; D009474:Neurons / Q000502:physiology / Q000648:ultrastructure; D010902:Pituitary Gland / Q000502:physiology*; D010904:Pituitary Gland, Posterior / Q000648:ultrastructure*; D051381:Rats; D013495:Supraoptic Nucleus / Q000648:ultrastructure*; D013569:Synapses / Q000648:ultrastructure; D013997:Time Factors
Ultrastrukturelle Veränderungen des supraoptico-neurohypophysären Systems nach Läsion des Hypophysenstiels bei der Ratte.