
TY  - JOUR
A1  - Shutt, DA 
A1  - Braden, AWH 
A1  - Lindner, HR 
T1  - Plasma coumestrol levels in sheep following administration of synthetic coumestrol or ingestion of medic hay (<I>Medicago littoralis</I>)
JF  - Australian Journal of Agricultural Research
JO  - Aust. J.  Agric. Res.
Y1  - 1969
VL  - 20
IS  - 1
SP  - 65
EP  - 69
KW  - 
UR  - https://doi.org/10.1071/AR9690065 
N2  - Administration of coumestrol to ovariectomized sheep by either intraruminal (i/r) infusion (350 mg/day) or intramuscular (i/m) injection (7.5-&ndash;25 mg/day) gave rise to mean plasma levels of 0.6-3.1 &#181;g coumestrol per 100 ml and to near-maximal stimulation of uterine growth. In addition the plasma contained water-soluble conjugates of coumestrol, hydrolysable by molluscan &#223;-glucuronidase; this fraction was quantitatively more important, relative to 'free' coumestrol, following i/r infusion of coumestrol, but seemed less closely related to oestrogenic action than was "free" plasmacoumestrol. Feeding on a ration of medic hay (Medicago littoralis), supplying approximately 146 mg coumestrol and 124 mg 4&#180;-methoxycoumestrol per day, gave rise to plasma levels of 0.5&ndash;0.7 &#181;g "free" coumestrol and 1.2&ndash;4.0 &#181;g conjugated coumestrol per 100 ml, and was associated with oestrogenomimetic changes in the composition of the cervical mucus. 4&#180;-methoxycoumestrol was not detected in the plasma, which suggested that this compound had been converted to coumestrol by O-demethylation in the medic-fed sheep. 
ER  -

