Therefore, if you're planning a long journey, you should always apply for the Russian visa before you leave. It's possible to get a tourist visa support at any moment before your journey, however, you can only apply for a tourist visa not earlier than 90 days before the date of your first entry to Russia.
Serotonin is a common neuromediator in the brain. It belongs to the group of so-called biogenic amines, relatively simple chemicals that facilitate the transfer of signals between the cells of the body.
Serotonin affects many aspects of your gut function, including: 1  It changes the motility of your bowels (how fast food moves through your system). 2  It affects how much fluid, such as mucus, is secreted in your intestines. 3  It affects how sensitive your intestines are to sensations like pain and fullness.erotonin is one of the most important neurotransmitters for that brain in your gut. Serotonin is important for the functions of your brain and your mood, but it is crucial to the function of your digestive system.