Simultaneous and Continuous Measurement of Choroid Plexus Blood Flow and Cerebrospinal Fluid Production: Effects of Vasoactive Intestinal Polypeptide

Using laser-Doppler flowmetry during ventriculocisternal perfusion with inulin-[14C]carboxylic acid, choroid plexus blood flow (CPBF) and CSF production were measured simultaneously in rats during periods of 3 h. Blood flow and CSF production decreased only slightly during control experiments. The effect of vasoactive intestinal polypeptide (VIP) was studied at different concentrations of the peptide given either intraventricularly or intravenously. Intraventricular administration of VIP (10−9 or 10−7 M) resulted in a decrease in CSF production of up to 30%, while CPBF increased by 20%, also demonstrating that CSF production and blood flow are not directly coupled in the choroid plexus. When infused intravenously, VIP (10 or 100 pmol/kg/min) increased CPBF, an effect partly antagonized at higher concentrations owing to a VIP-induced systemic hypotension. No effect of VIP on CSF production could be seen with intravenous administration.

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Chapter 58: Effects of vasoactive intestinal polypeptide on choroid plexus blood flow and cerebrospinal fluid production

Progress in Brain Research - Circumventricular Organs and Brain Fluid Environment - Molecular and Functional Aspects ◽

10.1016/s0079-6123(08)62365-1 ◽

1992 ◽

pp. 445-449 ◽

Cited By ~ 3

Author(s):

Christer Nilsson ◽

Maria Lindvall-Axelsson ◽

Christer Owman

Keyword(s):

Blood Flow ◽

Cerebrospinal Fluid ◽

Choroid Plexus ◽

Vasoactive Intestinal Polypeptide ◽

Fluid Production ◽

Intestinal Polypeptide

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Vasoactive intestinal polypeptide reduces hydrochloric acid-induced duodenal mucosal permeability

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1993.264.2.g272 ◽

1993 ◽

Vol 264 (2) ◽

pp. G272-G279 ◽

Cited By ~ 3

Author(s):

O. Nylander ◽

E. Wilander ◽

G. M. Larson ◽

L. Holm

Keyword(s):

Blood Pressure ◽

Blood Flow ◽

Vasoactive Intestinal Polypeptide ◽

Lesion Score ◽

Morphological Examination ◽

Mucosal Permeability ◽

Doppler Flowmetry ◽

Arterial Blood ◽

51Cr Edta ◽

Intestinal Polypeptide

The duodenum in anesthetized rats was perfused with HCl, and mucosal integrity was assessed by measuring the clearance of 51Cr-labeled EDTA from blood to lumen and/or by morphological examination (lesion score). Duodenal blood flow was determined by laser Doppler flowmetry and luminal alkalinization as well as H+ disappearance by backtitration. Intravenous infusion of vasoactive intestinal polypeptide (VIP; 13.5 micrograms.kg-1.h-1) increased luminal alkalinization threefold and decreased clearance of 51Cr-EDTA by 50%. VIP also decreased arterial blood pressure and induced a small and irregular decrease in duodenal blood flow. Perfusion with 10 mM HCl increased clearance of 51Cr-EDTA 2.1-fold, but the lesion score was not different from that in saline-perfused animals. Perfusion with 20 mM HCl increased clearance of 51Cr-EDTA four-fold and induced a greater lesion score than did 10 mM. Perfusion with either 10 or 20 mM HCl did not affect the duodenal blood flow. VIP reduced the rise in clearance of 51Cr-EDTA in response to 10 mM but not that to 20 mM HCl. Intravenous injection of prazosin (50 micrograms/kg) decreased luminal alkalinization, clearance of 51Cr-EDTA, blood pressure, and duodenal blood flow. In prazosin-pretreated rats, perfusion with 10 mM HCl increased clearance of 51Cr-EDTA 2.6-fold, and the lesion score was greater in this group than in animals infused with VIP. A positive linear correlation was obtained between HCO3- secretion and the mean rate of H+ disappearance.(ABSTRACT TRUNCATED AT 250 WORDS)

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Role of NaCl cotransport in cerebrospinal fluid production: effects of loop diuretics

Journal of Applied Physiology ◽

10.1152/jappl.1991.71.3.795 ◽

1991 ◽

Vol 71 (3) ◽

pp. 795-800 ◽

Cited By ~ 23

Author(s):

S. Javaheri

Keyword(s):

Cerebrospinal Fluid ◽

Choroid Plexus ◽

Ionic Composition ◽

Reasonable Assumption ◽

Cerebral Ventricles ◽

Fluid Production ◽

Production Effects ◽

Nacl Cotransport ◽

Csf Production

Cerebrospinal fluid (CSF) is secreted primarily by the choroid plexus (CP) located in the cerebral ventricles. Although much is known about ionic composition of cisternal CSF, the mechanisms involved in secretion of CSF in mammals are still not understood. The main aim of this report is to critically review the role of NaCl cotransport carrier in CSF production. On the basis of the studies in the literature, a model for CSF production by the CP is proposed. In this model, CP cells are assumed to be equipped with an NaCl cotransport carrier located on the basolateral (blood-facing) membrane. Because Na+ and Cl- are the two principal ions in CSF, their continued secretions into cerebral ventricles by CP cells require an adequate intracellular supply, which may be guaranteed by the NaCl cotransport carrier. Although this appears to be a reasonable assumption, making the processes involved in CSF production similar to those of other secretory epithelial cells, the presence of such a carrier in mammalian CP remains controversial. The reasons for this controversy are critically reviewed, and some suggestions for further studies are made.

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Innervation of the pancreas by substance P, enkephalin, vasoactive intestinal polypeptide and gastrin/CCK immunoractive nerves.

Journal of Histochemistry & Cytochemistry ◽

10.1177/27.9.479572 ◽

1979 ◽

Vol 27 (9) ◽

pp. 1283-1284 ◽

Cited By ~ 105

Author(s):

L I Larsson

Keyword(s):

Blood Flow ◽

Insulin Secretion ◽

Substance P ◽

Blood Vessels ◽

Vasoactive Intestinal Polypeptide ◽

Pancreatic Blood Flow ◽

Major Site ◽

Site Of Action ◽

Immunocytochemical Studies ◽

Intestinal Polypeptide

Immunocytochemical studies habe shown that many peptides which profoundly affect the endocrine and exocrine functions of the pancreas are localized to neurons. In the cat, such peptidergic nerves appear to innervate ganglia, islets and blood vessels of the pancreas, whereas their contributions to exocrine cells are minor. Our studies suggest that pancreatic ganglia represent one major site of action of the peptides and that, in addition, nerves containing the vasoactive intestinal polypeptide and gastrin/CCK-related peptides profoundly affect pancreatic blood flow and insulin secretion, respectively.

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