Age-related morphometrical changes of arteries of uterine wall in mares.

The research investigated the anatomical changes in uterine wall arteries of Thoroughbred broodmares as they age, finding that specific alterations such as increased intimal thickness and a decrease in medial thickness were significantly correlated with age and could potentially influence endometrial pathology.

Objective and Methodology of the Study

• The main aim of this study was to investigate the morphological changes that occur in the arteries of the uterine wall of Thoroughbred broodmares as they age.
• The study was conducted on uterine wall arteries from 13 mares aged between 2 to 31 years.
• Standard histomorphometry, a method of measuring the microscopic structure of tissues, was used in the investigation.
• In addition, electron microscopy was employed to ascertain the cross-sectional area of the tunica media (the middle layer of the artery wall) occupied by smooth muscle cells.

Findings of the Study

• Researchers found that the ratio of intimal (innermost) thickness to external diameter increased due to an increase (hyperplasia) of elastic fibers and was strongly correlated with the age of the mares.
• In contrast, the ratio of medial (middle layer) thickness to external diameter showed a decrease which was also significantly correlated with the age of the mares.
• Analysis using electron microscopy revealed that the cross-sectional area of the tunica media occupied by smooth muscle cells gradually decreased with the mares’ increasing age.

Implications and Conclusions of the Findings

• The findings of this study demonstrate that in the arteries of the uterine wall in mares, there is an increase in intimal elastic fiber and a thinning of the medial smooth muscular layer associated with aging.
• This suggests that these morphological changes in uterine wall arteries, which are reflective of natural aging processes, can potentially influence endometrial pathology, i.e., diseases associated with the lining of the uterus in mares.
• Such findings can be significant to equine health and fertility research, as understanding these age-related changes can help shape more effective veterinary interventions targeting reproductive health in horses, particularly broodmares.