Effects of centrally and systemically administered L-tyrosine and L-leucine on ovarian function in the old rat.
The effects of centrally and systemically administered L-leucine and L-tyrosine on ovarian function were studied in the old female rat. Systemically administered L-tyrosine reinstated regular vaginal cycling and ovulation, whereas systemically administered L-leucine did not. When administered centrally, through an indwelling cannula in the medial preoptic area, neither L-tyrosine nor L-leucine altered the ovarian or vaginal condition of the old female. When these females were subsequently treated with L-dopa, both systemic and central application were found to reinstate ovarian cycles. Potential mechanisms of action at the level of CNS monoaminergic neurotransmission are discussed.
D000375:Aging; D000818:Animals; D002395:Catecholamines / Q000378:metabolism; D004971:Estrus / Q000187:drug effects; D005260:Female; D007930:Leucine / Q000494:pharmacology*; D007980:Levodopa / Q000494:pharmacology; D010053:Ovary / Q000187:drug effects*; D011247:Pregnancy; D011301:Preoptic Area / Q000187:drug effects; D051381:Rats; D012701:Serotonin / Q000378:metabolism; D014443:Tyrosine / Q000494:pharmacology*
D002395:Catecholamines; D012701:Serotonin; D014443:Tyrosine; D007980:Levodopa; D007930:Leucine