[Tryptophan, its metabolism and function in the human body (with emphasis on metabolic diseases and depressive syndromes)].

There is shown a brief review of essential amino acid tryptophan. The tryptophan is known as the most precious essential amino acid. There is also presented review about synthesis, degradation and metabolism of tryptophan, about effects of tryptophan and degradation products of tryptophan. There are described diseases from pathologic metabolism and intake of tryptophan.