Cerebrospinal fluid gradients of somatostatin and substance P in neurological patients

Roesler, Nura; Gagnieu, Marie‐Claude; Blumberg, H.; S, Jost; Rißler, Klaus; Renaud, Bernard; Quincy, C; Cramer, H.

doi:10.1042/bst0141277

Cited by 2 publications

(1 citation statement)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition, E-24.11 and other peptidases, in contact with the CSF, might exert a protective role by ensuring that peptides that gain access to the CSF from within the CNS would be prevented from reaching, by the circulation of the CSF, distant but possibly responsive sites. In support of this possibility, radioimmunoassays of atrial natriuretic peptide and substance P have indicated that the concentrations of these peptides are an order of magnitude lower in the CSF than in plasma (Pernow, 1983;Roesler et al, 1986;Marumo et al, 1987).…”

Section: N (Ap-n) Onmentioning

confidence: 99%

Membrane peptidases in the pig choroid plexus and on other cell surfaces in contact with the cerebrospinal fluid

Bourne

Barnes

Taylor

et al. 1989

Biochemical Journal

View full text Add to dashboard Cite

A comprehensive survey of 11 peptidases, all of which are markers for renal microvillar membranes, has been made in membrane fractions prepared from pig choroid plexus. Two fractionation schemes were explored, both depending on a MgCl2-precipitation step, the preferred one having advantages in speed and yield of the activities. The specific activities of the peptidases in the choroid-plexus membranes were, with the exception of carboxypeptidase M, lower than in renal microvillar membranes: those of aminopeptidase N, peptidyl dipeptidase A ('angiotensin-converting enzyme') and gamma-glutamyltransferase were 3-5-fold lower, those of aminopeptidase A and endopeptidase-24.11 were 12-15 fold lower, and those of dipeptidyl peptidase IV and aminopeptidase W were 50-70-fold lower. Carboxypeptidase M had a similar activity in both membranes. Alkaline phosphatase and (Na+ + K+)-activated ATPase were more active in the choroid-plexus membranes. No activity for microsomal dipeptidase, aminopeptidase P and carboxypeptidase P could be detected. Six of the peptidases and (Na+ + K+)-activated ATPase were also studied by immunoperoxidase histochemistry at light- and electron-microscopic levels. Endopeptidase-24.11 and (Na+ + K+)-activated ATPase were uniquely located on the brush border, and the other two peptidases appeared to be much more abundant on the endothelial lining of microvessels. Dipeptidyl peptidase IV and aminopeptidase W were also detected in microvasculature. Pial membranes associated with the brain and spinal cord also stained positively for endopeptidase-24.11, aminopeptidase N and peptidyl dipeptidase A. The immunohistochemical studies indicated the subcellular fractionation did not discriminate between membranes derived from epithelial cells (i.e. microvilli) and those from endothelial cells. The possible significance of these studies in relation to neuropeptide metabolism and the control of cerebrospinal fluid production is discussed.

show abstract

Section: N (Ap-n) Onmentioning

confidence: 99%