Prostacyclin (PGX) is the endogenous metabolite responsible for relaxation of coronary arteries induced by arachindonic acid.

The actions of prostacyclin (PGX) and several other derivatives of arachidonic acid were examined on spiral-strips of bovine coronary artery. The strips were contracted by PGE2 and thromboxane A2. Although PGH2 usually cause a transient contraction followed by a relaxation, a few strips were only contracted whilst others were only relaxed.

Humoral response and blood pressure regulation during hypercapnia and haemorrhage in dogs.

1. The blood-bathed organ technique was used to study the release of catecholamines, angiotensin II and prostaglandin-like (PL) substances into the circulation during hypercapnia and after haemorrhage in anaesthetized dogs. 2.

Acidaemia produced by spinal stimulation in the pithed rat.

1. Electrical stimulation of the thoraco-lumbar spinal nervous outflow in the pithed rat preparation produces a fall in arterial blood pH.2.

Depressor responses to spinal stimulation in the pithed rat.

1. Electrical stimulation of the spinal nerves in the pithed rat preparation produces a pressor response due to sympathetic vasoconstriction.2.