Possible Interaction: Glutamine and Serotonin

“In this sense, serotonin hypoactivity could occur through a strong presynaptic inhibition of glutaminergic neurons via the subtype 5 of metabotropic glutaminergic receptors, and noradrenaline hypoactivity could be due to an enhanced presynaptic inhibition of GABAergic neurons via GABAB receptors.”

“Increased flux through the 5-HT pathway during hyperammonemia was indicated by a significant positive correlation between Gln concentration and the ratio of 5-HIAA to 5-HT in the brain of spf mice taken after microwave irradiation to prevent postmortem changes in metabolites.”

“1 … and glutamine release from control preparations, but no inhibition was observed from diabetic preparations with <0.1 mM. 10 … lactate production from control muscle but stimulation in diabetic preparations was observed only at 0.1 mM. Serotonin inhibited amino acid release and stimulated … in control and diabetic muscle.”

“Increasing concentrations of serotonin (1 nM-0.1 mM) produced a concentration-dependent decrease in the rate of alanine and glutamine release from muscle; intracellular levels of these amino acids were also decreased slightly by serotonin.”

“These data indicate that serotonin inhibits alanine and glutamine synthesis and release from intact skeletal muscle.”

“ Serotonin eliminates the induction of glutamine synthetase by hydrocortisone and potentiates the depressive action of glutamine on the induced enzyme.”

“Studies with protein synthesis inhibitors indicate that the action of serotonin on glutamine synthetase involves inhibition ofthe synthesis of the enzyme.”

“One example is serotonylation, which consists of covalent binding of 5-HT to the primary amine of glutamine.”