[Ventriculo-lumbar gradient of concentration of total cerebrospinal fluid proteins: 1 - mechanisms of origin]. / Gradiente ventrículo-lombar de concentração das proteínas totais do líquido cefalorraquiano: 1 - Mecanismo de origem.

In normal conditions there is a concentration gradient of proteins along the neuraxis. From a low level in the ventricles, ranging from 5 to 15 mg/10C ml, to an intermediate level in the cisterna magna, the protein content reaches its highest level in the lumbar sac, 12 to 44 mg/100 ml. Several mechanisms were considered to elucidate the origin of this gradient but many investigators think that the progressive increase of the protein concentration is best explained by the transfer of proteins from serum to the cerebrospinal fluid due to the relatively raised permeability of blood-cerebrospinal fluid barrier in the spinal subarachnoid space. This paper presents a study of the protein concentrations in cisternal and lumbar cerebrospinal fluid samples of patients with neurocysticercosis in activity. The 11 patients of the first group had free subarachnoid space communication between the cisterna magna and the lumbar sac; the 6 patients of the second group had a complete block of the subarachnoid space between these two levels. In every cerebrospinal fluid specimen the quantitative complement fixation test for cysticercus was performed and the titer determined in order to make an assessment of the central nervous system humoral immune response. The analysis of the data of this investigation shows that the concentration gradient of proteins is evident in the cerebrospinal fluid of patients with patency of the spinal subarachnoid space, and the ratio of concentrations of protein contents in simultaneous cisternal and lumbar samples was similar to that one observed in normal individuals. This gradient is also detected when the intensity of the humoral immune response is determined by quantitative complement fixation test for cysticercus in simultaneous cisternal and lumbar specimens. After the onset of spinal subarachnoid block, the confront of the results of the tests in cerebrospinal fluid samples, obtained before and after the blockage, shows a large increase both in the total protein content as well as the intensity of the humoral immune response, in the lumbar level. The similar increases both in protein concentration and titer of cysticercus complement fixation test in the lumbar fluid, in comparison with the cisternal fluid, in patients with patent spinal subarachnoid space, and the large simultaneous and similar increases in both protein content and titer of the cysticercus complement fixation test in the lumbar fluid of patients with spinal subarachnoid block are in disagreement with the usual explanation of the origin mechanisms of the gradient.(ABSTRACT TRUNCATED AT 400 WORDS)

[Ventriculo-lumbar gradient of concentration of total cerebrospinal fluid proteins: 2.- Influence of CSF drainage by ventriculoatrial shunt]. / Gradiente ventrículo-lombar de concentração das proteínas totais do líquido cefalorraquiano: 2 - Influencia da drenagem do LCR pela derivação ventrículo-atrial.

On a previous paper, based upon the data obtained from comparative studies of cerebrospinal fluid samples of two groups of patients with neurocysticercosis in activity, one with patency, the other one with blockage of the spinal subarachnoid space, evidence was presented that the concentration gradient of proteins along the neuraxis was the consequence of the escape of water from cerebrospinal fluid. The second paper is a continuance of that one. The material for this survey consisted of the clinical records of 11 patients with neurocysticercosis who during the course of the disease presented severe intracranial hypertension which required ventriculoatrial shunt as an emergency operation in order to allow survival. After surgery, it was observed a marked improvement in the clinical picture. Later, it was noticed a large increase in the protein content of the spinal fluid of the majority of the patients, as compared with the results verified prior to surgery. However, in these spinal fluid samples the increase in protein content was observed without a simultaneous rise in cell count, suggesting an improvement in the inflammatory condition. It seems very likely that this large elevation of the protein content in the subarachnoid fluid is the consequence of a reduction in the spinal fluid flow rate due to the ventricle-venous shunt.(ABSTRACT TRUNCATED AT 250 WORDS)

Gradiente ventriculo-lombar de concentracao das proteinas totais do liquido cefalorraquiano. 1 - Mecanismo de origem. / Ventriculo-lombar gradient of concentration of the total cerebrospinal fluid proteins: 1- Mechanism of origin

Foi feito estudo do mecanismo de origem do gradiente ventriculo-lombar de concentracao das proteinas totais do LCR baseado no comportamento da taxa das proteinas totais e do titulo da reacao de fixacao de complemento para cisticerco em pacientes com neurocisticercose em atividade. O aumento concomitante da taxa das proteinas totais e da intensidade da reacao imunitaria, em amostras simultaneas cisternal e lombar do LCR de pacientes com comunicacao livre no espaco subaracnoide espinhal, e as grandes elevacoes simultaneas destes dados da semiologia do LCR lombar de pacientes que apresentaram bloqueio do espaco subaracnoideo espinhal, indicam que o gradiente de concentracao das proteinas ao longo do neuro-eixo resulta da saida seletiva de agua