*2.1.3.2 Analysis of human plasma*

Aliquot of 50 μL human plasma was used for each sample analysis. The procedure including deproteinization is shown in **Figure 1**.

TRP metabolic pathways are shown in **Figure 1**.

**Figure 1** shows metabolic pathways of TRP. Metabolites were measured by an ultrahigh-speed liquid chromatography/mass spectrometry.

One-way ANOVA was used for evaluating statistical significance. A, b, c, and d indicate values of young and old men and women. Tukey's test was used for post hoc test.

**Table 2** shows that there are significant gender and age differences in plasma levels of TRP of healthy volunteers.

**137**

**Table 2.**

*Measurements of plasma levels of TRP metabolites in healthy volunteers.*

*Studies on Tryptophan Metabolites in Patients of Major Monopolar Depression*

young men and old women than in young women and old men.

Generally speaking, plasma levels of 5-hydroxyindoleacetic acid (5-HIAA), indole-3-acetic acid (IAA), KYN, and AA are higher in young women and old men than in young men and old women. Plasma levels of XA and 3HK are higher in

One-way ANOVA was used for evaluating statistical significance. A, b, c, and d indicate values of young and old men and women. Tukey's test was used for post

**Table 3** shows that in contrast to cases in healthy people, age and gender differ-

*DOI: http://dx.doi.org/10.5772/intechopen.91967*

ences disappeared in MMD except for KYN.

hoc test.

**Figure 1.** *Metabolic pathways of tryptophan.*

*Studies on Tryptophan Metabolites in Patients of Major Monopolar Depression DOI: http://dx.doi.org/10.5772/intechopen.91967*

Generally speaking, plasma levels of 5-hydroxyindoleacetic acid (5-HIAA), indole-3-acetic acid (IAA), KYN, and AA are higher in young women and old men than in young men and old women. Plasma levels of XA and 3HK are higher in young men and old women than in young women and old men.

One-way ANOVA was used for evaluating statistical significance. A, b, c, and d indicate values of young and old men and women. Tukey's test was used for post hoc test.

**Table 3** shows that in contrast to cases in healthy people, age and gender differences disappeared in MMD except for KYN.


#### **Table 2.**

*Melatonin - The Hormone of Darkness and Its Therapeutic Potential and Perspectives*

consideration of each range of measurement concentration.

ultrahigh-speed liquid chromatography/mass spectrometry.

dure including deproteinization is shown in **Figure 1**. TRP metabolic pathways are shown in **Figure 1**.

*2.1.3.2 Analysis of human plasma*

levels of TRP of healthy volunteers.

All mother solutions of 1 mg/mL had been stocked under −80°C, and standard samples for calibration curve were prepared prior to use as mixture solution by

Aliquot of 50 μL human plasma was used for each sample analysis. The proce-

**Figure 1** shows metabolic pathways of TRP. Metabolites were measured by an

One-way ANOVA was used for evaluating statistical significance. A, b, c, and d indicate values of young and old men and women. Tukey's test was used for post hoc test. **Table 2** shows that there are significant gender and age differences in plasma

**136**

**Figure 1.**

*Metabolic pathways of tryptophan.*

*Measurements of plasma levels of TRP metabolites in healthy volunteers.*


#### **Table 3.**

*TRP metabolite levels of patients of MMD.*
