Abstract / Summary
The natural amino acid, 5 – Hydroxytryptophan (5 – HTP) is intermediate metabolite of the essential amino acid tryptophan (Trp). Both 5 –HTP and Trp are precursor of a neurotransmitter serotonin (5 –tryptamine (5 – HT), often called the happiness hormone for its crucial role in regulating mood, sleep, appetite and digestion. In humans. There are two sites for serotonin synthesis, the gut provides approximately, 95 % of total body serotonin, most of which exists in plasma, and acts as a hormone, primarily regulating gut functions like gut motility, while the other site is the neurogenic neurons in the brain. The brain uses both tryptophan and 5 – hydroxytryptophan as precursors for serotonin synthesis because both can cross brain blood barrier (BBB), while serotonin found in the plasma cannot pass BBB. Although both Trp and 5 – HTP can cross the brain blood barrier “BBB” and reach the neurogenic neurons in brain where serotonin can be synthesized ,however, 5- hydroxytryptophan is generally recommended over tryptophan because it crosses the” BBB” at higher rate with minimum competition with the branched amino acids.In this study, using mice as widely used and well accepted animal model for such kind of study, the anti-radiation potential of different concentrations of 5 – HTP, alone and in combination with very low and nontoxic concentration of a sulfhydryl compound, S (2 - amino ethyl) isothiouronium bromide hydrobromide (AET) on survival, hair, and skin embedment. Significant encouraging results were obtained regarding survival, hair and skin health in treated animals. Moreover, successive administration three folds of this combination within an hour unwanted effects on survival, hair and skin embedment were observed 30 day after treatment.