Abstract
The activities of various presynaptic cholinergic parameters were determined in hippocampal synaptosomes of rats 29 weeks after intracerebroventricular injection of ethylcholine aziridinium (AF64A) (3 nmol/2 μl/side) or vehicle (saline). Synaptosomes were preloaded with [3H]choline ([3H]Ch), treated with diisopropyl fluorophosphate to inhibit cholinesterase activity and then were assayed for their content of [3H]Ch and [3H]acetylcholine ([3H]ACh) and for their ability to synthesize and release [3H]ACh. In synaptosomes from AF64A-treated rats compared with synaptosomes from vehicle-treated rats we observed that: (i) specific uptake of [3H]ACh was reduced to 60% of control; (ii) residing [3H]ACh levels were 43% of control while residing [3H]Ch levels were 72% of control; (iii) basal and K+-induced [3H]ACh release were 77% and 73% of control, respectively; (iv) high K+-induced synthesis of [3H]ACh was only 9% of control; (v) but, choline acetyltransferase activity remained relatively high, being 80% of control. These results suggest that AF64A-induced cholinergic hypofunction is expressed by both loss of some cholinergic neurons and impairment in the functioning of the spared neurons.
Original language | English |
---|---|
Pages (from-to) | 148-151 |
Number of pages | 4 |
Journal | Brain Research |
Volume | 586 |
Issue number | 1 |
DOIs | |
State | Published - 17 Jul 1992 |
Externally published | Yes |
Keywords
- AF64A
- Acetylcholine release
- Acetylcholine synthesis
- Cholinergic dysfunction
- Cholinergic toxicity
ASJC Scopus subject areas
- General Neuroscience
- Molecular Biology
- Clinical Neurology
- Developmental Biology