title: Effect of sympathetic stimulation on the blood brain barrier dysfunction induced by amphetamine and by epileptic seizures.
abstract: Stimulation of the sympathetic nerves to the brain is known to make the resistance vessels able to withstand a higher blood pressure, i.e. to prevent blood-brain barrier (BBB) dysfunction and overperfusion in acute hypertension. When hypertension occurs concomitantly with a metabolic vasodilatation e.g. during epileptic seizures and after amphetamine-administration, protein leakage in the brain is more pronounced than in hypertension per se. Unilateral stimulation of the cervical sympathetic chain during the administration of amphetamine or bicuculline--the latter a GABA-receptor blocking substance that induces epileptic activity--attenuated the leakage of Evans blue-albumin and 125IHSA into the brain. Our results thus indicate a prophylactic effect of sympathetic stimulation also when hypertension is combined with a metabolically induced vasodilatation. The sympathetic nerves may constrict both extracerebral arteries and intracerebral resistance vessels. Unexpectedly the effect on the BBB of unilateral stimulation was to a great extent bilateral under the present experimental conditions.
mesh_terms: D000818:Animals; D001640:Bicuculline / Q000494:pharmacology; D001794:Blood Pressure / Q000187:drug effects; D001812:Blood-Brain Barrier / Q000187:drug effects*; D003913:Dextroamphetamine / Q000494:pharmacology*; D004558:Electric Stimulation; D006973:Hypertension / Q000503:physiopathology; D008297:Male; D051381:Rats; D012640:Seizures / Q000503:physiopathology*; D013564:Sympathetic Nervous System / Q000502:physiology*
chemical_list: D003913:Dextroamphetamine; D001640:Bicuculline