Natriuresis following fourth ventricle perfusion with high-sodium artificial CSF.
Perfusion of the fourth cerebral ventricle with high-sodium artificial cerebrospinal fluid was found to result in an increase in urinary sodium excretion in anesthetized cats. The natriuresis was accompanied by an increase in blood pressure and glomerular filtration rate. However, in animals with the changes in blood pressure and glomerular filtration rate prevented by alpha adrenergic blockade (phenoxybenzamine), the increase in urinary sodium excretion persisted. the data suggest the presence of a neural mechanism in the vicinity of the fourth ventricle sensitive to cerebrospinal fluid sodium levels and capable of affecting urinary sodium excretion independent of changes in blood pressure or glomerular filtration rate. The possible role of the area postrema and adjacent medulla is considered.
D000317:Adrenergic alpha-Antagonists; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D001798:Blood Proteins; D001921:Brain / Q000378:metabolism*; D002415:Cats; D005919:Glomerular Filtration Rate / Q000187:drug effects; D006400:Hematocrit; D007552:Isotonic Solutions; D007668:Kidney / Q000187:drug effects*; D008297:Male; D009318:Natriuresis; D009994:Osmolar Concentration; D010477:Perfusion; D012964:Sodium / Q000134:cerebrospinal fluid* / Q000652:urine; D012965:Sodium Chloride; D013238:Stereotaxic Techniques; D013268:Stimulation, Chemical
D000317:Adrenergic alpha-Antagonists; D001798:Blood Proteins; D007552:Isotonic Solutions; D012965:Sodium Chloride; D012964:Sodium