GABAergic neurons of mammalian cerebral cortex: Widespread subclass defined by somatostatin content

Heterogeneity of GABAergic cells in cat visual cortex

“…The results of the present study confirm previous reports on the distribution of GAD-immunoreactive neurons in the cat visual cortex (Somogyi et al, 1983) and on the coexistence of this enzyme with the neuropeptides SRIF, NPY, and CCK in the rat, cat, and monkey visual cortex (Hendry et al, 1984b;Schmechel et al, 1984;Somogyi et al, 1984a;Jones and Hendry, 1986;Lin et al, 1986). In addition, we report here new evidence for the coexistence of a vitamin D-dependent calcium-bmdmg protein with GAD, and for the existence of a group of neurons positive both for VIP and CRF but not for GAD.…”

“…Neurons containing parvalbumin and GABA were preferentially associated with lay-ers II-VI of the rat cortex; cells double-labeled for GAD and CaBP occurred mainly in layers II and III of the cat cortex. Double-labeled cells As reported earlier (Hendry et al, 1984b;Schmechel et al, 1984;Somogyi et al, 1984a;Lin et al, 1986) the GAD-positive population can be subdivided into several subpopulations according to colocalization of the neuropeptides SRIF, NPY, and CCK. In addition, we found immunocytochemical evidence that the remaining GAD-positive neurons may be subdivided according to CaBP colocalization.…”

“…It has also been shown that GABAergic terminals can end on different parts of the target cell (Freund et al, 1983; and thereby exert different types of action on such cells. Recent immunocytochemical studies have shown that several peptides coexist with GABA (Hendry et al, 1984b;Schmechel et al, 1984;Somogyi et al, 1984a;Jones and Hendry, 1986;Lin et al, 1986). In addition, Somogyi et al (1984a) suggested that the presence of the peptides cholecystokinin (CCK) and somatostatin (SRIF) subdivides the GABAergic population of visual cortical cells.…”

5-HT3AReceptor-Bearing White Matter Interstitial GABAergic Interneurons Are Functionally Integrated into Cortical and Subcortical Networks

“…Basic morphological features of WMICs were indicative of a neuronal phenotype (Neuburger, 1922;Lund et al, 1975;Kostovic and Rakic, 1980;Chun and Shatz, 1989;Muller, 1994;Shering and Lowenstein, 1994;Eastwood and Harrison, 2005;Friedlander and Torres-Reveron, 2009;Loup et al, 2009), a notion that was also supported by electron microscopy data (Valverde and Facal-Valverde, 1988). While there is ample information about the immunohistochemical signature of WMICs, such as the expression of GABA and specific GABAergic interneuron markers (Innis et al, 1979;Adrian et al, 1983;Schmechel et al, 1984;Shults et al, 1984;Somogyi et al, 1984;Chan-Palay et al, 1985;Sandell, 1986;Yan et al, 1996;Bayraktar et al, 1997;Tao et al, 1999;Suárez-Solá et al, 2009), only a few studies focused on electrophysiological properties of WMICs (Clancy et al, 2001;Torres-Reveron and Friedlander, 2007;Friedlander and Torres-Reveron, 2009). The main hindrance for the identification of WMICs in acute slices is their scarcity.…”

Response:Epilepsy Hypothesis

“…Excluded from their analysis were the GABA-and GAD-positive basket cells within or subjacent to the granule cell layer. Immunocytochemical experiments conducted in this laboratory with antiserum to GABA, with the use of the high glutaraldehyde fixation Ribak Schmechel and colleagues (8), has addressed the colocalization of somatostatin and GAD in the hippocampus of the rat (8), the species used in our studies (3,4); and Ribak appears to have misinterpreted their results. They found that, whereas there was a high degree of coexistence of somatostatin and GAD in most hippocampal subregions, it was clearly lower in the dentate hilus.…”