Earlier we have described the role of glucocorticoids in ontogenetic regulation. Present paper reviewed the literature data on possible participation of glucocorticoid interactions with somatolactogens (growth hormone, prolactin) and related peptides (insulin-like growth factor-I, oxytocin) in ontogeny, especially in aging. The bibliographic analysis included also evaluation of these hormones as antistress or anticatabolic factors. It was concluded that such important bioactivities of somatolactogens and related peptides are necessary for optimizing immune defense and survival, in spite of the observed negative influences on life expectancy of at least some of them. It appears also that more complex hormonal interactions should be considered for interpretation of these paradoxical data.