Biomaterial Database

Blood-brain barrier opening following transient reflex sympathetic hypertension. 1994

T Ijima, and Y Kubota, and T Kuroiwa, and H Sankawa

Department of Anesthesiology, School of Dentistry, Tokyo Medical and Dental University, Japan.

Numerous researchers have shown that experimentally induced hypertension opens the blood-brain barrier (BBB), whereas physiologically induced hypertension is accompanied by sympathetic activation, which exerts a protective effect on the BBB via cerebral vasoconstriction. It has not yet been established that transient reflex sympathetic hypertension can open the BBB. In this study, 14 lightly-anesthetized adult cats were subjected to electrical stimulation of a tooth and transient reflex sympathetic hypertension (duration of less than 60 s) was elicited repeatedly. Continuous flowmetry of the cerebral blood flow showed that autoregulation breakthrough occurred. Light halothane anesthesia supplemented with 30 or 60% nitrous oxide, or 1.2% halothane anesthesia occasionally suppressed the elicited pressor response and prevented such breakthrough. Leakage of Evans blue (EB), which was administered before the hypertensive insult, was confirmed in the marginal and suprasylvian gyri in 5 cats. The EB positive cats reached a significantly (p < 0.05) higher mean arterial blood pressure (198 +/- 16 mmHg) during reflex sympathetic hypertension than EB negative cats (189 +/- 19 mmHg). Breakthrough occurred 16 times in EB positive, but only 8 times in EB negative cats. In conclusion, transient reflex sympathetic hypertension can elicit cerebrovascular autoregulation breakthrough and if the breakthrough occurs repeatedly it is followed by the opening of the BBB.

UI	MeSH Term	Description	Entries
D006973	Hypertension	Persistently high systemic arterial BLOOD PRESSURE. Based on multiple readings (BLOOD PRESSURE DETERMINATION), hypertension is currently defined as when SYSTOLIC PRESSURE is consistently greater than 140 mm Hg or when DIASTOLIC PRESSURE is consistently 90 mm Hg or more.	Blood Pressure, High,Blood Pressures, High,High Blood Pressure,High Blood Pressures
D009619	Nociceptors	Peripheral AFFERENT NEURONS which are sensitive to injuries or pain, usually caused by extreme thermal exposures, mechanical forces, or other noxious stimuli. Their cell bodies reside in the DORSAL ROOT GANGLIA. Their peripheral terminals (NERVE ENDINGS) innervate target tissues and transduce noxious stimuli via axons to the CENTRAL NERVOUS SYSTEM.	Pain Receptors,Receptors, Pain,Nociceptive Neurons,Neuron, Nociceptive,Neurons, Nociceptive,Nociceptive Neuron,Nociceptor,Pain Receptor
D012018	Reflex	An involuntary movement or exercise of function in a part, excited in response to a stimulus applied to the periphery and transmitted to the brain or spinal cord.
D001794	Blood Pressure	PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.	Systolic Pressure,Diastolic Pressure,Pulse Pressure,Pressure, Blood,Pressure, Diastolic,Pressure, Pulse,Pressure, Systolic,Pressures, Systolic
D001812	Blood-Brain Barrier	Specialized non-fenestrated tightly-joined ENDOTHELIAL CELLS with TIGHT JUNCTIONS that form a transport barrier for certain substances between the cerebral capillaries and the BRAIN tissue.	Brain-Blood Barrier,Hemato-Encephalic Barrier,Barrier, Blood-Brain,Barrier, Brain-Blood,Barrier, Hemato-Encephalic,Barriers, Blood-Brain,Barriers, Brain-Blood,Barriers, Hemato-Encephalic,Blood Brain Barrier,Blood-Brain Barriers,Brain Blood Barrier,Brain-Blood Barriers,Hemato Encephalic Barrier,Hemato-Encephalic Barriers
D001929	Brain Edema	Increased intracellular or extracellular fluid in brain tissue. Cytotoxic brain edema (swelling due to increased intracellular fluid) is indicative of a disturbance in cell metabolism, and is commonly associated with hypoxic or ischemic injuries (see HYPOXIA, BRAIN). An increase in extracellular fluid may be caused by increased brain capillary permeability (vasogenic edema), an osmotic gradient, local blockages in interstitial fluid pathways, or by obstruction of CSF flow (e.g., obstructive HYDROCEPHALUS). (From Childs Nerv Syst 1992 Sep; 8(6):301-6)	Brain Swelling,Cerebral Edema,Cytotoxic Brain Edema,Intracranial Edema,Vasogenic Cerebral Edema,Cerebral Edema, Cytotoxic,Cerebral Edema, Vasogenic,Cytotoxic Cerebral Edema,Vasogenic Brain Edema,Brain Edema, Cytotoxic,Brain Edema, Vasogenic,Brain Swellings,Cerebral Edemas, Vasogenic,Edema, Brain,Edema, Cerebral,Edema, Cytotoxic Brain,Edema, Cytotoxic Cerebral,Edema, Intracranial,Edema, Vasogenic Brain,Edema, Vasogenic Cerebral,Swelling, Brain
D002415	Cats	The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)	Felis catus,Felis domesticus,Domestic Cats,Felis domestica,Felis sylvestris catus,Cat,Cat, Domestic,Cats, Domestic,Domestic Cat
D002540	Cerebral Cortex	The thin layer of GRAY MATTER on the surface of the CEREBRAL HEMISPHERES that develops from the TELENCEPHALON and folds into gyri and sulci. It reaches its highest development in humans and is responsible for intellectual faculties and higher mental functions.	Allocortex,Archipallium,Cortex Cerebri,Cortical Plate,Paleocortex,Periallocortex,Allocortices,Archipalliums,Cerebral Cortices,Cortex Cerebrus,Cortex, Cerebral,Cortical Plates,Paleocortices,Periallocortices,Plate, Cortical
D003782	Dental Pulp	A richly vascularized and innervated connective tissue of mesodermal origin, contained in the central cavity of a tooth and delimited by the dentin, and having formative, nutritive, sensory, and protective functions. (Jablonski, Dictionary of Dentistry, 1992)	Dental Pulps,Pulp, Dental,Pulps, Dental
D004558	Electric Stimulation	Use of electric potential or currents to elicit biological responses.	Stimulation, Electric,Electrical Stimulation,Electric Stimulations,Electrical Stimulations,Stimulation, Electrical,Stimulations, Electric,Stimulations, Electrical