EFFECT OF PROPYLTHIOURACIL-INDUCED HYPOTHYROIDISM ON CEREBRAL-CORTEX OF YOUNG AND AGED RATS - LIPID-COMPOSITION OF SYNAPTOSOMES, MUSCARINICRECEPTOR-SITES, AND ACETYLCHOLINESTERASE ACTIVITY

The effect of hypothyroidism on the lipid composition of synaptosomes, density and affinity of muscarinic receptor sites, and acetylcholines terase activity in the cerebral cortex of young and aged rats was inve stigated. The animals were made hypothyroid by adding 0.05% propyl-2-t hiouracil to their drinking water for four weeks. This pathological st ate induced an increase in the relative percentage of sphingomyelin in young rats. In aged rats hypothyroidism induced a decrease of sphingo myelin and glycerophosphocholine and an increase of cholesterol. The e ffect of hypothyroid state on cerebral cortex resulted in an increase of acethylcholinesterase activity both in young and aged rats and was also reflected in an increase of density of M1-AChRs but only in the f ormer.