We studied trophic effects of angiotensin II, vasopressin and oxytocin on explanted ventral spinal cord cultures from 13-14-old day rat embryos. There was a significant neurite promoting effect in angiotensin II and vasopressin-treated cultures. Angiotensin II had the most potent effect at any concentrations. It became clear that minimum effective concentration was 10(-8) M in angiotensin II and vasopressin respectively. Effect of these two neuropeptides was concentration-dependent. However, oxytocin had no neurotrophic effect at any concentrations. Our results demonstrated that angiotensin II and vasopressin have a neurotrophic effect on ventral spinal cord in cultures, and may contribute to therapeutic strategy of amyotrophic lateral sclerosis.