scholarly journals Stimulation by acetylcholine of phosphatidylinositol labelling. Subcellular distribution in rat cerebral-cortex slices

1972 ◽  
Vol 126 (5) ◽  
pp. 1141-1147 ◽  
Author(s):  
Eduardo G. Lapetina ◽  
Robert H. Michell
Keyword(s):  
Cerebral Cortex ◽  
Specific Radioactivity ◽  
Neuronal Cell ◽  
Subcellular Fractionation ◽  
Rat Cerebral Cortex ◽  
Marker Enzymes ◽  
Fresh Tissue ◽  
Cell Structures ◽  
Neuronal Cell Bodies ◽  
Cortex Slices

1. Rat cerebral-cortex slices were incubated with 32Pi, acetylcholine and eserine for periods of 10min and 2h. The specific radioactivity of phosphatidylinositol was elevated during these treatments by 36 and 106% respectively. 2. The specific radioactivities of the phosphatidylinositol in different cell structures were determined after subcellular fractionation. They were highest in the nuclear, microsomal and synaptic-vesicle fractions and lowest in myelin, both in the controls and in the acetylcholine-treated slices. 3. The stimulated labelling of phosphatidylinositol was relatively evenly distributed: no subcellular fraction showed a stimulation markedly higher than that in the homogenate. 4. Studies of the distributions and activities of marker enzymes indicated that the subcellular fractionation achieved was similar to that with fresh tissue. 5. The results are discussed in relation to the previous report that the stimulation is observed throughout the neuronal cell-bodies and in relation to the hypothesis that the labelled phosphatidylinositol produced by stimulation is a component of an acetylcholine-receptor proteolipid localized in the synaptic junction.

scholarly journals A study on the precursors of the acetyl moiety of acetylcholine in brain slices. Observations on the compartmentalization of the acetyl-coenzyme A pool

1970 ◽  
Vol 118 (3) ◽  
pp. 443-450 ◽  
Author(s):  
R. Nakamura ◽  
S.-C. Cheng ◽  
H. Naruse
Keyword(s):  
Cerebral Cortex ◽  
Guinea Pig ◽  
Specific Radioactivity ◽  
Brain Slices ◽  
Rat Cerebral Cortex ◽  
Rat Striatum ◽  
Metabolic Compartmentation ◽  
Cortex Slices ◽  
Guinea Pig Brain

1. A method was devised for the determination of the specific radioactivity of the acetyl moiety of acetylcholine synthesized from various 14C-labelled substrates. 2. The precursor for the acetyl moiety of acetylcholine was studied in slices of striatum and cerebral cortex from rat and guinea-pig brain. Incorporation of radioactivity into acetylcholine was determined after incubating the slices in the presence of [2-14C]acetate, [14C]bicarbonate, [1,5-14C]citrate, dl-[1- or 5-14C]glutamate or [1- or 2-14C]pyruvate. 3. After incubation for 1h, acetylcholine was accumulated significantly in both striatum slices (4.1nmol/mg of protein) and cerebral-cortex slices (0.57nmol/mg of protein) from the rat. Final concentrations were about 11 and 5 times respectively the initial values. 4. With slices from rat striatum, rat cerebral cortex and guinea-pig cerebral cortex, the specific radioactivity of acetylcholine derived from [2-14C]pyruvate was very high, reaching approx. 30, 20 and 6% respectively of the initial specific radioactivity of added pyruvate in the medium. With the striatum slices this high value was reached after incubation for 15min. Incorporation of radioactivity from [2-14C]acetate was only 1.25, 5.3 and 19.7% of that from [2-14C]pyruvate in rat striatum, rat cerebral-cortex and guinea-pig cerebral-cortex slices respectively. A small but definite incorporation was found from [5-14C]glutamate. No incorporation was found from the other substrates. The findings suggest that pyruvate is the most important precursor for the synthesis of the acetyl moiety of acetylcholine in brain slices. 5. The specific radioactivity of acetylcholine relative to that of citrate when [2-14C]pyruvate was used compared with that obtained when [2-14C]acetate was used. A marked difference was found in all slices, suggesting metabolic compartmentation of the acetyl-CoA pool.

Cortex: Topography and Organization

2021 ◽  
pp. 175-178
Author(s):  
Richard J. Caselli ◽  
David T. Jones
Keyword(s):  
Cerebral Cortex ◽  
Visual Cortex ◽  
Gray Matter ◽  
Striate Cortex ◽  
Neuronal Cell ◽  
Area 17 ◽  
Neuronal Cell Bodies ◽  
Brodmann Areas ◽  
Functional Components ◽  
Complex Activities

The cerebral cortex is involved in various simple and complex activities. It consists of layers of neuronal cell bodies (ie, gray matter) that are organized into gyri (convolutions).The cortex can be divided into functional components in several ways. Various schemes are based on function, cytoarchitecture, topography, or Brodmann areas. The terminology can be confusing because the same area of cortex could be designated by several names. For instance, Brodmann area 17 is also called the primary visual cortex, the striate cortex, and the calcarine cortex. Brodmann designated 52 regions of the cerebral cortex according to cytoarchitecture.

Phosphorylation of MARCKS by endothelin in rat cerebral cortex slices

1999 ◽  
Vol 24 (3) ◽  
pp. 155-162 ◽  
Author(s):  
Mar�a J. P�rez-Alvarez ◽  
M. Carmen Calcerrada ◽  
R. Edgardo Catal�n ◽  
Ana M. Mart�nez
Keyword(s):  
Cerebral Cortex ◽  
Rat Cerebral Cortex ◽  
Cortex Slices
Sign in / Sign up

Export Citation Format

Share Document