Morphological changes in spiral artery of the mammalian ovary with age.

Morphological changes which take place in ovarian arteries at different ages in human and monkey, were investigated by light microscopy, transmission electron microscopy and scanning electron microscopy. The ovarian arteries in both species were characterized by a spiral configuration throughout their course. The hilar and medullar arteries were especially convoluted. In the pubertal monkey, the hilar and medullary arteries exhibited some intimal thickenings in which smooth muscle cells of a synthetic phenotype were longitudinally arranged. These arteries in adult monkeys had considerable intimal thickening. In a 30-year-old woman, arteries with intimal thickenings were detected in the hilus and medulla. Around 40 years of age, the intima of the arteries were considerably thickened with a diameter usually equal to half of the wall. In women after menopause, the tunica intima of these arteries was approximately two-thirds or more of the total artery wall thickness. Spiral arteries of the ovary were also thickened with advancing age.