Oxytocin is a cyclic nonapeptide hormone with amino acid sequence CYIQNCPLG that also acts as a neurotransmitter in the brain, it is a uterine contraction drug that can be extracted from the posterior pituitary gland of the animal or chemically synthesized. The chemical synthesis product does not contain vasopressin and has no boosting effect. It has a selective excitatory effect on uterine smooth muscle and strengthens its contraction. The uterus is most sensitive to oxytocin (increased estrogen secretion), the immature uterus is not responsive to this product, the uterus is less responsive to oxytocin in the first or second trimester of pregnancy, and gradually increases in the second trimester, reaching the highest level before labor . A small dose can strengthen the rhythmic contraction of the smooth muscles at the bottom of the uterus, making it stronger in contraction, speeding up the contraction frequency, the contraction properties are similar to natural labor, and maintaining polarity and symmetry, so it is used clinically to induce labor and induce labor. Large doses make the uterine muscles to exhibit ankylosing contraction. It is used clinically to compress the interfibrous blood vessels to prevent postpartum hemorrhage and postpartum insufficiency. It also promotes lactation, shrinks the ducts of the breast, and promotes milk excretion from the breast, but it cannot increase the secretion of milk. Can only promote breast milk.

Specification

Appearance

White to off-white amorphous powder

Solubility

Very soluble in water (>1mg/ml)

Identification By HPLC

Retention time is same with the reference substance

Molecular Ion Mass

1007.2±1

Amino Acid Composition

±10%

Purity (HPLC) :

NLT 98.0 %

Related Substances(HPLC)

Total impurities <2.0%

Any individual impurity: <1.0%

Acetic acid (HPLC)

5.0 to 10.0%

pH  (20 mg/mL in water)

3 to 6

Water Content

≦10 %

Activity

≧400IU/mg

Bacterial Endotoxins : 

≦200IU/mg

a. Physiological effect

(1) Effect on the breast: The breast during lactation continuously secretes milk under the action of prolactin and is stored in breast acinar. Oxytocin shrinks myoepithelial-like cells around breast acinars, and promotes breast milk with lactation.

(2) Effect on the uterus: Oxytocin has a strong contraction promoting effect on the uterus, but it is more sensitive to the uterus during pregnancy. Estrogen increases the sensitivity of the uterus to oxytocin, while progesterone does the opposite.

(3) Effect on social shyness and autism: Oxytocin can help people who have been left out in social situations due to shyness to overcome the feeling of social shyness. But oxytocin nasal sprays don't work for people who are already confident.

(4) When the mood is cheerful or has a strong sense of belonging, the heart will secrete oxytocin and the stress will be relieved. At the same time, the amount of oxygen supplied by the tissues in the body increased significantly.

b. Special effect

Affect baby-mother relationship

Some experiments have shown that in infancy with people who have established a close relationship, after using oxytocin, mothers in memory will become more caring and considerate; and from people who are relatively indifferent to their mothers in infancy, oxytocin will deepen his indifference. Good memories.

c. Women's Divorce Gene

Test results show that women who carry A-allele, a variant of the oxytocin receptor gene, are generally more difficult to maintain a close relationship with others, and it is more difficult to enter the marriage hall. Even if they get married, they are 50% more likely to get married or eventually divorce than women who do not carry the genetic variant. Researchers call A-allele a "divorce gene." Men who marry women with a "divorce gene" have lower marriage satisfaction.

d. Secretory regulation

Oxytocin secretion is mainly regulated by neuroreflexivity. When the baby sucks the nipple, the stimulation information is transmitted to the supraoptic and paraventricular nucleus of the hypothalamus, which causes the secretion of oxytocin and causes the mammary glands to eject, called the ejection reflex, which is a neuroendocrine reflex. On this basis, a conditioned reflex can be formed, and crying or stroking the baby can cause ejaculation.

During childbirth, the cervix and vagina are oppressed and pulled, which can reflect the secretion of oxytocin and help the childbirth. Although oxytocin can stimulate uterine contraction, it is not a determinant of uterine contraction during delivery. In addition, emotional responses such as panic and anxiety can inhibit oxytocin secretion..

Side effect of Oxytocin

With oxytocin during sacral block, severe hypertension can occur, and even cerebral vascular rupture. Cannot be injected in the same solution as noradrenaline. Compatibility with hydrolyzed proteins is contraindicated.

Some cosmetics may have added oxytocin, and there are also "spray oxytocin" sales on the Internet, and even some people buy autism that hopes to cure children. In this regard, scientists expressed deep concern.