Sudden (acute) colitis. If your dog suddenly develops colitis, it is probably induced by stress, such as boarding, moving, severe weather or some other change in lifestyle, or it could be from a dietary indiscretion, such as emptying the garbage can, too many treats or a sudden change in diet.
âVitamin D is needed for the production of brain chemicals such as dopamine and norepinephrine and acetylcholine. These brain chemicals are known to improve and increase attention span, and its concentration in the brain is directly correlated with the ability to focus for sustained periods of time.â.
Norepinephrine Synthesis and Release. Norepinephrine (NE) is the primary neurotransmitter for postganglionic sympathetic adrenergic nerve s. It is synthesized inside the nerve axon, stored within vesicles, then released by the nerve when an action potential travels down the nerve.Below are the details for release and synthesis of NE: 1  The amino acid tyrosine is transported into the sympathetic nerve axon. The amino acid tyrosine is transported into the sympathetic nerve axon. 2  Tyrosine (Tyr) is converted to DOPA by tyrosine hydroxylase (rate-limiting step for NE synthesis). 3  DOPA is converted to dopamine (DA) by DOPA decarboxylase.