ULTRASTRUCTURE OF HYPOTHALAMIC NEUROSECRETORY NUCLEI OF DORMOUSE (ELIOMYS-QUERCINUS L) IN AWAKENING AND HIBERNATING STATES

  • 1 January 1978
    • journal article
    • research article
    • Vol. 127  (OCT) , 239-249
Abstract
The ultrastructure of the chief neurosecretory nuclei, supraoptic (SON), paraventricular (PVN) and infundibular (IN) of the dormouse (E. quercinus) was studied during active and hibernating states. In the active state, all 3 nuclei contained light, dark and intermediate neurons. In hibernation, the SON showed only a single light type differing from the light neurons of the active state; the endoplasmic reticulum was vacuolized and sometimes grouped in honeycomb structures; and the cytoplasm contained accumulations of filamentous crystalline material. None of these features occurred in the active state neurons. In the PVN and IN during hibernation, a light and dark neuron were present. Honeycomb structures were seen in neurons of the PVN during hibernation, but never in those of the IN. Specific morphological features in the SON and PVN appear associated with the physiological changes of hibernation.