Do active substances of the thymus influence the processes of aging? I. Effects of treatment with embryonal and early fetal thymic calf extracts (ETCE) on some organs of grown-up young mice.

Our previous investigations indicated that embryonal and early fetal thymic calf extracts (ETCE), unlike those obtained from adult thymus, cause lymphopenia and hypogammaglobulinemia, counteract anaphylactic shocks and prolong the survival of allografts and xenografts in adult rodents. This paper presents the level of unsaturated fatty acid peroxides and the morphology of some organs in adult mice treated parenterally with ETCE. ETCE treatment resulted in the fall in the level of cerebral and splenic unsaturated fatty acid peroxides. Histology of thymus, liver and spleen in mice injected with ETCE remained similar to that of corresponding neonatal mouse organs. Experimental results, supplemented by such previous observations as longevity of some animals treated with ETCE, disappearance of presbyopia and climacteric symptoms in people treated with embryonal thymus per os, suggest that active substances produced by embryonal and early fetal thymus not only affect the immunological system but also interfere with the processes of organ differentiation and aging.