The β-subunit of hCG gonadotropin (beta-hCG) contains 145 amino acids, encoded by six highly homologous genes that are arranged in tandem and inverted pairs on chromosome 19q13.3 - CGB (1, 2, 3, 5, 7, 8). It is known that CGB7 has a sequence slightly different from that of the others.The two subunits create a small hydrophobic core surrounded by a high surface area-to-volume ratio: 2.8 times that of a sphere. The vast majority of the outer amino acids are hydrophilic.beta-hCG is mostly similar to beta-LH, with the exception of a Carboxy Terminus Peptide (beta-CTP) containing four glycosylated serine residues that is responsible for hCGs longer half-life. Function
Human chorionic gonadotropin interacts with the LHCG receptor of the ovary and promotes the maintenance of the corpus luteum for the maternal recognition of pregnancy at the beginning of pregnancy. This allows the corpus luteum to secrete the hormone progesterone during the first trimester. Progesterone enriches the uterus with a thick lining of blood vessels and capillaries so that it can sustain the growing fetus.It has been hypothesized that hCG may be a placental link for the development of local maternal immunotolerance. For example, hCG-treated endometrial cells induce an increase in T cell apoptosis (dissolution of T cells). These results suggest that hCG may be a link in the development of peritrophoblastic immune tolerance, and may facilitate the trophoblast invasion, which is known to expedite fetal development in the endometrium.
Nadolol, sold under the brand name Corgard among others, is a medication used to treat high blood pressure, heart pain, atrial fibrillation, and some inherited arrhythmic syndromes. It has also been used to prevent migraine headaches and complications of cirrhosis. It is taken orally.Common side effects include dizziness, feeling tired, a slow heart rate, and Raynaud syndrome. Serious side effects may include heart failure and bronchospasm. Its use in pregnancy and breastfeeding is of unclear safety. It is a non-selective beta blocker and works by blocking β1-adrenergic receptors in the heart and β2-adrenergic receptors in blood vessels.Nadolol was patented in 1970 and came into medical use in 1978. It is available as a generic medication. In 2016, it was the 283rd most commonly prescribed medication in the United States, with more than a million prescriptions. Medical uses
Nadolol is used to treat hypertension and for long-term treatment of angina pectoris and is approved by the FDA for these purposes.It is regularly used off-label for control of heart rate in people with atrial fibrillation, prevention of migraine headaches; prevention of bleeding veins in people with portal hypertension caused by cirrhosis; and to treat people with high levels of thyroid hormone.Nadolol is the preferred beta-blockers in the management of patients with LQTS for prevention of ventricular arrhythmia. It is more efficacious than selective beta blockers or propranolol in the prevention of breakthrough cardiac events.