BIOMOLECULES AND ENZYMES

Detailed explanation-1: -Prolactin. Prolactin is necessary for the secretion of milk by the cells of the alveoli. The level of prolactin in the blood increases markedly during pregnancy, and stimulates the growth and development of the mammary tissue, in preparation for the production of milk (19).

Detailed explanation-2: -The luteinizing hormone (LH) remains low during lactation but at weaning, LH concentrations increase as prolactin levels decrease.

Detailed explanation-3: -During breastfeeding, FSH serum levels remain at a level comparable to that observed during the follicular phase of normal ovulatory cycles (Glasier et al., 1983; Shaaban et al., 1987). Therefore, anovulation associated with breastfeeding has not been ascribed to alterations in FSH secretion.

Detailed explanation-4: -Quantities of milk produced are very variable. The role of all the following hormones in lactogenesis are described: prolactin; adrenocorticotropin (ACTH, which stimulates glucocorticoid secretion); estrogens; placental lactogens. Maintenance of intense lactation also depends on a complex of hormones.