It is supposed that these improvements of clinical symptoms are based on inhibition of vasoconstriction and platelet aggregation in pulmonary circulation.
Reduced invasion will leave the spiral arteries vasoreactive, and thus more likely to undergo spontaneous transient vasoconstriction.
Activation of the extrinsic coagulation pathway causes additional adherence of platelets and even greater vasoconstriction.
Traditionally phenylephrine was reserved as a second-line drug for obstetrics because of concern about potential uteroplacental vasoconstriction.
Elevated high-density lipoprotein levels ameliorate abnormal vasoconstriction in early atherosclerosis.
When the core temperature falls, the hypothalamus increases core heat production and causes vasoconstriction which minimizes heat transfer to the skin.
In particular, these studies showed that large doses of vasopressors caused vasoconstriction in the uteroplacental circulation which could result in fetal hypoxia.
First, ongoing perfusion of the placenta may cause continuous stimulation of production of vasoactive substances, which will tend to increase placental vasoconstriction.
