[Asp5]-Oxytocin

[Asp5]-Oxytocin is the first 5-position neurohypophyseal hormone analogue possessing significant biological activity. [Asp5]-Oxytocin causes uterine contractions in vitro, enhanced by Mg2+. [Asp5]-Oxytocin has the ability of rat uteroconstrictor, avian vasodilator, and rat antidiuretic.