title: An electron microscopical morphometrical study on pinealocytes of pregnant rats.
abstract: A morphometrical study was made on the cut-surface of the pinealocytes in electron micrographs of the pineals from pregnant, puerperal and non-pregnant female rats. No significant differences in the cross-sectional area of the pinealocytes and the nuclei or in the nucleo-cytoplasmic ratio were found among the three groups of pregnant, puerperal and non-pregnant rats. The cross-sectional area of the nucleoli was, however, larger in the pinealocytes of the rats in pregnancy and early puerperium. This has been statistically confirmed by the ranking method (the U-test) of Wilcoxon, Mann and Whitney. The enlargement of nucleoli suggests the enhanced function of the pineal in pregnancy and early puerperium.
mesh_terms: D000375:Aging; D000818:Animals; D005260:Female; D008854:Microscopy, Electron; D010870:Pineal Gland / Q000254:growth & development / Q000502:physiology / Q000648:ultrastructure*; D011247:Pregnancy; D011270:Pregnancy, Animal; D051381:Rats; D012741:Sexual Maturation