Changes in the conformation of the rat mammary artery during reproductive cycle

Rights statement
Awarding institution
  • University of Strathclyde
Date of award
  • 2008
Thesis identifier
  • T12563
Qualification Level
Qualification Name
Department, School or Faculty
  • Mammary gland is a characteristic organ in mammals, it gained this from its development, adaptation, and function. The developments of mammary gland are stimulated by a complex of repeated stimuli during different stages of the reproductive cycle. The mammary gland undergoes periodic development at oestrus cycle and during pregnancy, this development prepares the gland to fulfill its function. The amount of milk yield is dependent on the blood flow. The rate of blood flow change during different stages of the reproductive life is regulated by local factors that are secreted by the mammary epithelial cells, hormonal stimuli, and nerves within the gland. One of the important hormones is oestrogen, which plays an important role in regulating mammary artery tone, causing relaxation effect during pregnancy, but still the mechanism of this regulation is unknown. The cardiac output is increased during pregnancy and lactation. Blood flow within the mammary gland is regulated by a number of local factors, which increased the rate of blood flow during lactation to satisfy the high requirement of gland to nutrients and hormonal stimuli. The blood flow regulates through adjustment the tone of the mammary artery; this was shown by a number of studies in many species, regardless to the location of the mammary gland or the origin of the mammary artery. There is a strong relationship between blood flow within the mammary gland and milk production. The aim of this study is to open the window on the remodelling that occurs to the wall and lumen of the mammary artery, at three stages of the reproductive life, which are pregnancy, lactation, and after weaning. While a number of studies showed that uterine artery tone is regulated by steroid hormones, oestrogen and progesterone, by stimulating the oestrogen receptors located on the endothelium and smooth muscles of the uterine artery, this may help to understand the mechanism of remodelling that occurs in mammary artery. The results did show that the lumen dimensions changed at different stages along the term of pregnancy, lactation, and post lactation. This accompanied with an adaptation in the arterial wall thickness. The wall thickness was at minimum thickness during lactation while the luminal diameter was at maximum. At post-lactation stage, the luminal diameter reduced and the arterial wall thickness tend to return to normal, but with slight increase in thickness.
Resource Type
Date Created
  • 2008
Former identifier
  • 814304