Atosiban is a co-receptor antagonist of oxytocin and vasopressin V1A, and the oxytocin receptor is similar in structure to the vasopressin V1A receptor. When the oxytocin receptor is blocked, oxytocin can still play a role through the V1A receptor, so it is necessary to block the above two receptor pathways at the same time, and a single antagonistic receptor can effectively inhibit uterine contraction. This is one of the main reasons why beta-agonists, calcium channel blockers and prostaglandin synthase inhibitors are not effective in inhibiting uterine contraction (see related literature)
