The nature of the transmitters for both nerves, however, is not positively determined, nor is the functional role of these nerves clarified. Light and electron microscopy will provide details of sites of storage of the transmitter and of the neuromuscular relationship. Biochemical analysis will help to understand the synthesis of transmitter substances and the coupling mechanisms involved in vasomotor responses. Since the neuroeffector and myo-endothelial mechanisms may change with age and diseases such as hypertension and stroke, a detailed examination of this process in brain arteries under such diseased conditions is currently underway . Inhibition of cerebral neurogenic vasodilation by L-glutatmine and nitric oxide synthase inhibitors.
Norepinephrine attenuates serotonin inhibition of pial venous tone.
Endothelial messengers and cerebral vascular tone regulation. Dopamine constricts porcine pial veins. Cholinergic, nitric oxidergic innervation in cerebral arteries of the cat. Extracts of Ginkgo biloba and ginsenosides exert cerebral vasorelaxation via a nitric oxide pathway. Mechanism of nicotine-induced relaxation in the porcine basilar artery.