A mammary gland is an exocrine gland in humans and other mammals that produces milk to feed young offspring. Mammals get their name from the Latin word mamma"breast". The mammary glands are arranged in organs such as the breasts in primates for example, humans and chimpanzeesthe udder in ruminants for example, cows, goats, and deerand the dugs of other animals for example, dogs and cats.
Each breast has 15 to 20 sections, or lobes, that surround the nipple in a radial manner, like spokes on a wheel. Inside these lobes are smaller sections, called lobules. At the end of each lobule are tiny "bulbs" that produce milk.
Metrics details. Involution of the mammary gland is an essential process that removes the milk-producing epithelial cells when they become redundant at weaning. It is a two-step process that involves the death of the secretory epithelium and its replacement by adipo-cytes.
Human Cell. Recent studies have demonstrated that breast milk contains a population of cells displaying many of the properties typical of stem cells. This review outlines progress made in this newly emerging field of stem cell biology and provides an analysis of the available data on purification, propagation and differentiation of certain types of progenitor cells from breast milk.
Lactationsecretion and yielding of milk by females after giving birth. The milk is produced by the mammary glandswhich are contained within the breasts. The breasts, unlike most of the other organscontinue to increase in size after childbirth.
The breasts are specialised organs, which are located on the anterior chest wall. The female breast is more developed than the male breast, as their primary function is to produce milk for nutrition of the infant and baby. There are lots of glands in our breasts, which grow and develop during puberty and maturation.
Mammary gland development during puberty and reconstruction during pregnancy and lactation is under the control of circulating endocrine hormones, such as growth hormone, which are released from the pituitary. In this study, we explored the influence of overexpression of growth hormone in the mammary gland on breast development and milk production in goats. Using transcriptome sequencing, we found that the number of highly expressed genes was greater in GH transgenic goats than non-transgenic goats.
Cold Spring Harbor, NY — Anecdotal reports of nursing mothers have long suggested that giving milk is a lot easier in second and subsequent pregnancies, compared with a first pregnancy. Their work shows the mammary gland forms a long-term memory of pregnancy that primes it to respond to the hormonal changes that announce succeeding pregnancies. The results appear online today in Cell Reports. Secretion of the hormones estrogen and progesterone set the stage for dramatic changes that take place in the breast during pregnancy: a massive proliferation of mammary epithelial cells, and the formation of thousands of ductal structures, which support milk production and transport during lactation.
Metrics details. Milk is synthesized by mammary epithelial cells of lactating mammals. The synthetic capacity of the mammary gland depends largely on the number and efficiency of functional mammary epithelial cells.
At birth, the mammary gland contains only rudimentary ducts that have small club-like ends, which grow throughout childhood. During puberty the breast begins to enlarge through the formation of adipose tissue and the branching and elongation of the ductal system. However, it is during pregnancy that the most significant growth and development of the breast occurs. In the first half of pregnancy secretory differentiation the differentiation of alveolar epithelial cells into milk-secreting cellsductal branching and lobular formation of the breast mammogenesis occur.