Uterine catecholamines and prostaglandins during the estrous cycle of the rat.
The uterine contents of norepinephrine, epinephrine, dopamine, and prostaglandins F and E were determined on each day of the rat estrous cycle. Catecholamines were determined by high performance liquid chromatography with electrochemical detection (HPLC-EC) as well as by a radioenzymatic technique; prostaglandins were quantitated by RIA. The norepinephrine and dopamine values obtained by the radioenzymatic assay were approximately 1.5 times as high as the values obtained by HPLC-EC (norepinephrine, 285 vs. 188 ng/g; dopamine, 11.0 vs. 7.5 ng/g). Despite this difference in levels, both analytic techniques showed a decline in uterine norepinephrine from diestrus to estrus, followed by a significant (P less than 0.01) increase in norepinephrine on the day of metestrus. A cyclic pattern was also revealed for uterine dopamine concentration. There was a decline in dopamine concentration from diestrus to proestrus (radioenzymatic, P less than 0.01), followed by a return to high levels at metestrus (HPLC-EC). Epinephrine levels were low (undetectable by radioenzymatic assay; 24 ng/g by HPLC-EC) and showed no variation during the estrous cycle. Prostaglandin F was uniformly higher than prostaglandin E (10 vs. 2.5 ng/uterus). Significant increases in the uterine contents of both prostaglandins were shown on the day of proestrus.
D000818:Animals; D002395:Catecholamines / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D004031:Diestrus; D004298:Dopamine / Q000378:metabolism; D004837:Epinephrine / Q000378:metabolism; D004971:Estrus; D005260:Female; D008686:Metestrus; D009638:Norepinephrine / Q000378:metabolism; D011247:Pregnancy; D011359:Proestrus; D011453:Prostaglandins / Q000378:metabolism*; D011458:Prostaglandins E / Q000378:metabolism; D011460:Prostaglandins F / Q000378:metabolism; D051381:Rats; D014599:Uterus / Q000378:metabolism*
D002395:Catecholamines; D011453:Prostaglandins; D011458:Prostaglandins E; D011460:Prostaglandins F; D004298:Dopamine; D009638:Norepinephrine; D004837:Epinephrine