动物造模,药效评价 z-bio 2024-09-02 379

　　The rapid growth and development of the gastrointestinal tract in newborns after birth, and its regulatory mechanism is still not fully understood. Breast milk, with its balanced and comprehensive nutrition, is considered the most ideal diet and has a significant promoting effect on the growth and development of the gastrointestinal tract in newborns. Meanwhile, other intestinal nutrients, hormones, and growth factors are also involved in this process. After birth, newborns can only digest and absorb various nutrients through the gastrointestinal tract. Therefore, once human milk feeding begins, newborns begin to adapt to intestinal food and bacterial colonization, and begin the development of the gastrointestinal tract. The development of the intestine is reflected in rapid changes in its structure and functional parameters, such as enhanced digestive enzyme activity, increased nutrient absorption, and improved immune function. The development of the stomach is gradually completed before and after birth, and the adaptive changes of the stomach are most obvious when its nutrient intake changes from liquid milk to solid food. The neonatal period is the most rapid and important period for the development of the gastrointestinal tract. However, the gastrointestinal tract of newborns is very fragile and easily affected by various factors and diseases, such as food nutrition, food form, gut microbiota, necrotizing enterocolitis or gastrointestinal malformations. This not only affects the intake of gastrointestinal nutrients, but also leads to delayed growth and development of the gastrointestinal tract and even atrophy of the gastrointestinal mucosa. Therefore, it is necessary to replicate different animal models of feeding and gastrointestinal diseases in order to adjust the diet of newborns, explore the pathogenesis and treatment methods of diseases, avoid the occurrence of diseases or shorten the course of the disease, and promote the healthy growth of newborns.

　　The miniature pig model is commonly used for research on the regulatory effect of colostrum on the development of the gastrointestinal tract in newborns. Previous studies have shown that colostrum can promote protein synthesis in intestinal mucosal cells and the formation of intestinal enzyme systems, but the mechanism is not clear; The regulatory effects of hormones and growth factors on gastrointestinal development. Hormones are closely involved in the regulation of neonatal gastrointestinal growth and development, mainly including adrenal cortex hormones, thyroid hormones, growth hormones, and gastrointestinal hormones. They exert regulatory effects through direct stimulation or synergistic effects with intestinal nutrients and growth factors, and their relationships are complex and require further research; The role of bacterial colonization in the development of the gastrointestinal tract and the acquisition of immune function in the body. For newborns, bacterial colonization and enteral nutrition are very important for their early gastric development and immune acquisition. However, for premature infants, bacterial colonization and enteral nutrition can lead to obvious intestinal inflammation and diseases, such as necrotizing enterocolitis, and the underlying reasons need further exploration. At present, research has confirmed that although neonatal gastrointestinal bacteria are influenced by maternal vaginal microbiota, the main source of intestinal bacteria, lactobacilli, and bifidobacteria is maternal feces. The colonization of these microorganisms takes some time and is easily disrupted by other physical conditions, such as obstructed breast milk intake, greatly reduced immunoglobulin intake, low body resistance, and microbial colonization becoming invasive. These subtle relationships need to be further clarified in animal models; The impact of necrotizing enterocolitis on the development of gastrointestinal tract is a very common disease in newborns. Both incidence rate and mortality are high, and people attach great importance to it. The study of this disease has been for a long time and has made some progress, but there are still many problems to be solved; The impact of parenteral nutrition on the adaptation process of the gastrointestinal tract. Extraintestinal nutrition is a common nutritional support method for newborns, especially premature infants. The composition and timing of parenteral nutrition vary among newborns with different physical conditions. This nutritional method has a significant regulatory effect on gastrointestinal development and nutrient absorption. The above are all problems faced by the gastrointestinal development of newborns, while the gastrointestinal development of premature infants faces more complex problems. Among them, smooth adaptation of the gastrointestinal tract is a fundamental issue for the survival of premature infants. In addition, it also includes the ability to tolerate enteral and parenteral nutrition. Immature sucking, swallowing, breathing, or ataxia among the three can lead to hypoxia, apnea, bradycardia, and inability to rely solely on oral feeding in premature infants. As an organism, the study of the impact of one action on the development of the gastrointestinal tract and other systems in premature infants is particularly important.