title: Effects of serotonin on the heartbeat of pond snails in a hunger state.
abstract: Serotonin (5-hydroxytryptamine: 5-HT) is a multimodal transmitter that controls both feeding response and heartbeat in snails. However, the effects of 5-HT on the hunger state are still unknown. We therefore examined the relation among the hunger state, the heartbeat rate and the 5-HT action in food-starved snails. We found that the hunger state was significantly distinguished by the heartbeat rate in snails. The heartbeat rate was high in the food-satiated snails, whereas it was low in the food-starved snails. An increase in 5-HT concentration in the body boosted the heartbeat rate in the food-starved snails, but did not affect the rate in the food-satiated snails. These results suggest that 5-HT application may mimic the change from a starvation to a satiation state normally achieved by direct ingestion of food.
authors: Kagawa School of Pharmaceutical Sciences, Tokushima Bunri University, Sanuki 769-2193, Japan.
authors: Miki
authors: M
authors: Yamagishi
authors: Research Institute for Electronic Science, Hokkaido University, Sapporo 060-0812, Japan.
authors: Takayuki
authors: T
authors: Watanabe
authors: Kagawa School of Pharmaceutical Sciences, Tokushima Bunri University, Sanuki 769-2193, Japan.
authors: Dai
authors: D
authors: Hatakeyama
authors: Kagawa School of Pharmaceutical Sciences, Tokushima Bunri University, Sanuki 769-2193, Japan.
authors: Etsuro
authors: E
authors: Ito
keywords: Lymnaea; food satiation; food starvation; heartbeat; serotonin