Atrial natriuretic peptide augments the blood-brain transfer of water but not leucine and glucose.
Recent evidence predicts an effect of atrial natriuretic peptide (ANP) on the blood-brain transfer of water. To test this prediction, we measured the blood-brain transfer of water, L-leucine, and D-glucose in 9 brain regions of male rats after intravenous injection of 10 pmol ANP. The peptide elicited an increase of the permeability-surface area (PaS) product of labeled water by 28-108% while the PaS products of leucine and glucose remained unchanged. Cerebral blood flow increased 15-48% while cardiac output and plasma volume in brain did not alter, indicating no change of capillary surface area (CSA). Regionally, the CSA varied from 63 cm2/g (striatum) to 97 cm2/g (colliculi) and the fraction of capillaries contributing to the total vascular volume varied from 29% (olfactory bulb/lobe) to 62% (striatum). The blood-brain barrier (BBB) permeability to water (5.7 micron/s) was an order of magnitude higher than to glucose (0.4 micron/s) or to leucine (0.3 micron/s).
Brust
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P
Universität Leipzig, Sektion Biowissenschaften, F.R.G.
Baethmann
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Gjedde
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Ermisch
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A
D000818:Animals; D009320:Atrial Natriuretic Factor / Q000494:pharmacology*; D001812:Blood-Brain Barrier / Q000187:drug effects*; D001834:Body Water / Q000378:metabolism*; D001921:Brain / Q000033:anatomy & histology; D002560:Cerebrovascular Circulation / Q000187:drug effects; D005947:Glucose / Q000378:metabolism*; D007930:Leucine / Q000378:metabolism*; D008297:Male; D008353:Mannitol; D051381:Rats; D011919:Rats, Inbred Strains
D008353:Mannitol; D009320:Atrial Natriuretic Factor; D007930:Leucine; D005947:Glucose