Each day, about 9 liters of fluid enters the duodenum. Most chemical digestion takes place in the duodenum by chemicals secreted by the liver, pancreas and small intestine. The other two sections of the small intestine, the jejunum and the ileum, absorb food molecules by way of the villi directly into the blood stream.
Histamine is synthesised in the brain in the hypothalamus, in a specific area known as the tuberomamillary nucleus (TMN), where it acts as a signalling messenger (or neurotransmitter). The hypothalamus is the area of the brain that overseas the metabolic processes of the body found in the central nervous system.
When the histamine system is dysregulated the body acts like there is danger when there is not, and can result in the following symptoms, all of which have histamine as their root cause: 1. Adrenal Fatigue. H3R regulates the sympathetic nervous system, through the adrenal glands, and plays a role in the release of hormones under stress. Histamine activates the release of corticosterone through the activation of the hypothalamus-adrenal axis by H1R. Adrenal fatigue is quite common with histamine intolerance.