Depolarization-dependent release of [3H]-norepinephrine was studied using the pheochromocytoma clone, PC12. Norepinephrine release in response to nicotinic receptor stimulation or elevated K+ was enhanced substantially by 3-deazaadenosine, a compound known to cause inhibition of S-adenosylmethionine-dependent transmethylations. The enhancement was evident at a 3-deazaadenosine concentration as low as 10−5 M and increased with concentration. Simultaneous addition of L-homocysteine thiolactone increased the effects of 3-deazaadenosine. These results suggest that either transmethylations play some role in stimulation/secretion or that inhibition of transmethylations can indirectly enhance secretion.
ASJC Scopus subject areas
- General Biochemistry, Genetics and Molecular Biology
- Pharmacology, Toxicology and Pharmaceutics(all)