Abstract
The relevance of serotonin and in particular that of 5-HT 3 receptors is unequivocal with respect to emetic/antiemetic effects, but it is controversial with respect to antidiabetic effects. The effects of tropisetron (5-HT 3 receptor antagonist) and various ginger ( Zingiber officinale) extracts (known to interact with the 5-HT 3 receptor channel system) were investigated. Serotonin (32 to 500 µM) inhibits insulin release (RIA) from INS-1 cells which is reversed by tropisetron (10 to 100 µM) and two different ginger extracts (spissum and an oily extract). Their effects are obvious even in the absence of serotonin but are more pronounced in its presence (doubled to tripled). Specific 5-HT 3 binding sites are present in INS-1 cells using 0.4 nM [ 3H] GR65630 in displacement experiments. The in vitro data with respect to ginger are corroborated by in vivo data on glucose-loaded rats showing that blood glucose (Glucoquant ®) is decreased by ~ 35% and plasma insulin (RIA) is increased by ~ 10%. Both the spissum extract and the oily ginger extract are effective in two other models: they inhibit [ 14C] guanidinium uptake into N1E-115 cells (model of 5-HT 3 effects) and relax rat ileum both directly and as a serotonin antagonistic effect. Other receptors addressed by ginger are 5-HT 2 receptors as demonstrated by using methysergide and ketanserin. They weakly antagonize the serotonin effect as well. It may be concluded that serotonin and in particular the 5-HT 3 receptor channel system are involved in modulating insulin release and that tropisetron and various ginger extracts can be used to improve a diabetic situation.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.