Effect of prepubertal retinyl palmitate treatment on uterine development and subsequent uterine capacity in swine.

Abstract

The effect of prepubertal retinyl palmitate treatment on uterine development and uterine capacity was determined. Gilts remained intact or were unilaterally hysterectomized-ovariectomized (UHO) on d 28, 84, or 112 of age. Starting at birth, half of the gilts in each UHO group were treated with retinyl palmitate (14,000 IU.kg-1.wk-1) and half received control carrier solution. All intact gilts received control carrier solution. Blood samples (d 28, 56, 84, and 112 of age) were analyzed for retinoid and retinol-binding protein (RPB). At UHO, part of the excised uterine horn was processed for morphometric analysis of the uterine wall, and tissues were incubated in minimal essential medium with [3H]leucine to assess total protein and RBP production. After puberty, gilts were mated and then killed on d 44 to 47 of pregnancy; uterine length, number of corpora lutea and fetuses, and fetal, placental, and empty uterine weights were recorded. Endometrial tissues were incubated in minimal essential medium with [3H]leucine, and nondialyzable radioactivity, acid phosphatase, and RBP production were measured. During the prepubertal period, retinyl palmitate treatment decreased (P < .05) myometrial area (longitudinal and circular), but it had no effect on other components of the uterine wall or production of nondialyzable radioactivity or secretion of RBP by uterine tissue. During pregnancy, prepubertal retinyl palmitate treatment increased (P < .05) uterine length but had no effect on uterine weight, number of fetuses, placental or fetal weights, or endometrial production of nondialyzable radioactivity, acid phosphatase, or RBP. Therefore, prepubertal retinyl palmitate treatment at the dosage administered had no effect on uterine capacity.