The effect of tryptamine on serotonin release from hypothalamic slices is mediated by a cholinergic interneurone

✍ Scribed by Christine Ennis; Barry Cox

• Publisher: Springer
• Year: 1982
• Tongue: English
• Weight: 429 KB
• Volume: 78
• Category: Article
• ISSN: 0033-3158
• DOI: 10.1007/bf00470595

✦ Synopsis

Tryptamine produced a concentration-related inhibition of potassium-evoked release of tritium from slices of rat hypothalamus preloaded with 3 H-serotonin. This effect of tryptamine was blocked by a series of serotonin antagonists with a relative order of potency 'which suggested that tryptamine was acting on a post-junctional serotonin receptor. However, the response to tryptamine was also blocked by tetrodotoxin, indicating that tryptamine may be acting indirectly via the release of a second neurotransmitter. The finding that physostigmine enhanced, whilst atropine antagonised the effect of tryptamine suggests that the second neurotransmitter may be acetylcholine. This possibility is discussed.