Acta Univ. Palacki. Olomuc., Fac. Med. Volume 143, 2000 | DOI: 10.5507/bp.2000.008

ULTRASTRUCTURE OF SYNAPSES IN THE SUPRAOPTIC NUCLEUS OF THE CAT AFTER INDUCED HYPOTHERMIA

Jarmila Malínská^a, Jiří Malínský^b

^a Department of Normal Anatomy, Medical Faculty, Palacký University, Hněvotínská 3, 775 15 Olomouc, Czech Republic

^b Department of Microscopic Methods, Medical Faculty, Palacký University, Hněvotínská 3, 775 15 Olomouc, Czech Republic

Ultrastructure of axosomatic (AS) and axodendritic (AD) synapses in the supraoptic nucleus (NSO) wasinvestigated in a group of normothermic cats and compared with another group of cats after short-term inducedhypothermia. Quantitative analysis demonstrated a significant decrease of number of AS synapses, smaller size ofAD synaptic knobs, shorter length of the synaptic contact and an increase of the active zone. Evaluation of theshape of the synaptic cleft demonstrated an increase of both positive (P) and negative (N) types in hypothermicanimals. The observed morphological changes can be ascribed to the decreased synaptic activity in a greater part ofthe synaptic population and to the increased activity in a smaller portion of synapses.

Keywords: Supraoptic nucleus, Cat, Synapses, Induced hypothermia

Published: July 1, 2000  Show citation