Excretion of estrone, estradiol, and progesterone in the urine and feces of the female cotton-top tamarin (Saguinus oedipus oedipus).

Abstract

The excretion of three gonadal steroids was studied in the urine and feces of female cotton-top tamarins (Saguinus oedipus oedipus). Each steroid, 14C-estrone, 14C-estradiol, and 14C-progesterone, was injected into a separate female cotton-top tamarin. Urine and feces were collected at 8 hr intervals for 5 days on the three tamarins. Samples were analyzed to determine the proportion of free and conjugated steroids. Steroid excretion patterns were determined by sequential ether extraction, enzyme hydrolysis, and chromatography. Labeled estrone was excreted in a slow and continuous manner into the urine (57%) and feces (43%) with 90% of the steroid conjugated. The nonconjugated form had an elution profile identical to 3H estrone, but the conjugated portion was not completely hydrolyzed by enzyme. Labeled estradiol was excreted primarily in the urine (87%) and was released rapidly. Over 90% of the injected 14C-estradiol was excreted in urine as a conjugate, of which 41% was converted to an estrone conjugate and the remaining 59% was excreted as a polar estradiol conjugate. Labeled progesterone was excreted primarily in the feces (95%), 61% of which was free steroid. Four to six individual peaks of radioactivity were found when using celite chromatography and high performance liquid chromatography (HPLC), indicating that progesterone is metabolized into several urinary and fecal metabolites. One of these peaks matched 3H-progesterone and others may be pregnanediols, pregnanetriols, and 17-hydroxyprogesterone. These steroidal excretion patterns help explain the atypical hormonal patterns seen during the tamarin ovarian cycle.