Purpose: To evaluate the morphological changes in murine cornea upon metoclopramide-induced hyperprolactinemia during the proestrous phase or pregnancy.
Methods: Forty adult mice were divided into two groups: (control) CTR1 and (treated with metoclopramide (MET1). After fifty days, half of the mice were sacrificed. The remaining animals were mated, and then labeled as pregnant controls (CTR2). Part of these animals were treated with metoclopramide and constituted the metoclopramide-treated pregnant (MET2) group. The groups CTR2 and MET2 were sacrificed on the 6th day of pregnancy. The hormonal levels were assessed by chemioluminescence and radioimmunoassay methods and the cornea was removed for the histomorphometric study.
Results: The epithelial, stromal, endothelial and total thickness in the experimental group was: MET1 and MET2 were higher than one in the control group: CTR1 and CTR2. There was a significant reduction of the hormonal level in the animals that received metoclopramide as compared to controls (CTR1: estradiol = 156.6 +/- 42.2 pg/ml; progesterone = 39.4 +/- 5.1 ng/ml; prolactin = 130.4 +/- 26.2 ng/ml; MET1: estradiol = 108.0 +/- 33.1 pg/ml; progesterone = 28.0 +/- 6.4 ng/ml; prolactin = 551.5 +/- 23.3 ng/ml; CTR2: estradiol = 354.0 +/- 56.0 pg/ml; progesterone = 251.0 +/- 56.0 ng/ml; prolactin = 423.2 +/- 28.1 ng/ml; MET2: estradiol = 293.0 +/- 43.0 pg/ml; progesterone = 184.0 +/- 33.0 ng/ml; prolactin = 823.1 +/- 51.1 ng/ml).
Conclusion: The metoclopramide-induced hyperprolactinemia may increase corneal layers, mainly in pregnant mice. Possibly, this effect is related to reduction in estrogen and progesterone production.