TY - JOUR
T1 - Regulation of cerebral microcirculation - Update
AU - Tomita, Minoru
AU - Suzuki, Norihiro
AU - Hamel, Edith
AU - Busija, David
AU - Lauritzen, Martin
PY - 2000/1/1
Y1 - 2000/1/1
N2 - The present symposium during Brain 99 was convened to explore the current aspects of the neural (extrinsic and intrinsic) and chemical control of the microvasculature in the brain with specific relevance to stimuli and rapid flow responses. N. Suzuki demonstrated the presence of neurokinin-1 receptors along the axons of vasoactive intestinal polypeptide-containing cerebrovascular parasympathetic nerves. Since the receptors were activated by substance P, calcitonin gene-related peptide and neurokinin released from coexisting sensory nerve fibers, the parasympathetic (vasodilating) fibers could effect rapid local flow increases. N. Suzuki, however, considered this as part of an elaborate defensive network protecting the brain from invasions by noxious substances. E. Hamel discussed the responses of the microvessels to neurotransmitters and suggested that nitric oxide (NO) released from intrinsic neurons may serve as a relay in the flow activation responses by intracerebral cholinergic fibers originating in the basal forebrain nuclei. D. Busija summarized a vasodilating system of activated N-methyl-D-asparate receptors located on neurons involving Ca influx-NO production, and activated ATP-sensitive potassium channels located in the vascular system. According to Busija, such interactions were disrupted during hypoxia and ischemia due to cyclooxygenase-derived superoxide anion. M. Lauritzen observed a 10 times larger increase in blood flow on stimulation of the climbing nerve as compared with that following the parallel nerve stimulation. The former transmitters are considered by him to be NO and K, and the latter NO and adenosine. Each speaker singled out NO as a common mediator for the microvasculature in the rapid local flow increases.
AB - The present symposium during Brain 99 was convened to explore the current aspects of the neural (extrinsic and intrinsic) and chemical control of the microvasculature in the brain with specific relevance to stimuli and rapid flow responses. N. Suzuki demonstrated the presence of neurokinin-1 receptors along the axons of vasoactive intestinal polypeptide-containing cerebrovascular parasympathetic nerves. Since the receptors were activated by substance P, calcitonin gene-related peptide and neurokinin released from coexisting sensory nerve fibers, the parasympathetic (vasodilating) fibers could effect rapid local flow increases. N. Suzuki, however, considered this as part of an elaborate defensive network protecting the brain from invasions by noxious substances. E. Hamel discussed the responses of the microvessels to neurotransmitters and suggested that nitric oxide (NO) released from intrinsic neurons may serve as a relay in the flow activation responses by intracerebral cholinergic fibers originating in the basal forebrain nuclei. D. Busija summarized a vasodilating system of activated N-methyl-D-asparate receptors located on neurons involving Ca influx-NO production, and activated ATP-sensitive potassium channels located in the vascular system. According to Busija, such interactions were disrupted during hypoxia and ischemia due to cyclooxygenase-derived superoxide anion. M. Lauritzen observed a 10 times larger increase in blood flow on stimulation of the climbing nerve as compared with that following the parallel nerve stimulation. The former transmitters are considered by him to be NO and K, and the latter NO and adenosine. Each speaker singled out NO as a common mediator for the microvasculature in the rapid local flow increases.
KW - ATP-sensitive potassium channel
KW - Electrical-vascular correlates
KW - Intracerebral cholinergic innervation
KW - Neurokinin-1 receptor
KW - NMDA receptors
UR - http://www.scopus.com/inward/record.url?scp=0034155169&partnerID=8YFLogxK
U2 - 10.2302/kjm.49.26
DO - 10.2302/kjm.49.26
M3 - Journal article
C2 - 10750378
AN - SCOPUS:0034155169
SN - 0022-9717
VL - 49
SP - 26
EP - 34
JO - Keio Journal of Medicine
JF - Keio Journal of Medicine
IS - 1
ER -