title: Age-related changes in central nervous system enkephalins and substance P.
mesh_terms: D000375:Aging; D000818:Animals; D001921:Brain / Q000378:metabolism*; D004723:Endorphins / Q000378:metabolism*; D004743:Enkephalin, Leucine; D004744:Enkephalin, Methionine; D004745:Enkephalins / Q000378:metabolism*; D007031:Hypothalamus / Q000378:metabolism; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013373:Substance P / Q000378:metabolism*; D001615:beta-Endorphin
chemical_list: D004723:Endorphins; D004745:Enkephalins; D013373:Substance P; D004744:Enkephalin, Methionine; D004743:Enkephalin, Leucine; D001615:beta-Endorphin