[Relationship between opioid peptides and mediator systems in children].

Examinations of 98 healthy children and prepubertal and pubertal adolescents have revealed sex-related differences in blood plasma levels of beta-endorphin and methionine-enkephalin: the content of these peptides was higher in pubertal boys. Blood plasma leucin enkephalin content of boys and girls was virtually unchanged over the entire period of sexual maturation. Analysis of correlations helped detect the relationship between the examined peptides and the end product of catecholamine metabolism, vanilmandelic acid, and a negatively significant relationship between beta-endorphin and serotonin levels.