The parvalbumin-containing nonpyramidal neurons in the rat hippocampus

Abstract

The calcium-binding protein parvalbumin is considered to be involved in the control of intracellular ion homeostasis of highly active inhibitory neurons. A review of the light and electron microscopical features as well as the identified synaptic connections of these neurons is presented. Parvalbumin-containing neurons are mostly located within or in the vicinity of the granule or pyramidal cell layer. They form a subgroup of GABAergic neurons that has a target specificity for the cell body region. Their fine structural characteristics are identical to those known for hippocampal inhibitory neurons. Parvalbumin-containing neurons are involved in several inhibitory pathways: feed-back inhibition, feed-forward inhibition and disinhibition. The functional implications of our own as well as published data are discussed. Special consideration is given to the possible physiological role of parvalbumin in these neurons.

Reduction of posttraumatic transneuronal "early gene" activation and dendritic atrophy by the N-methyl-D-aspartate receptor antagonist MK-801.

“…It may be of interest that persisting dendritic retraction after entorhinal lesion has been shown exclusively for parvalbumincontaining cells (10) and not for dentate granule cells (28). Granule cells lack this calcium-binding protein (17). Our results suggest a pronounced activation of c-fos in parvalbumin-containing neurons (Fig.…”

“…This allows for an analysis of distal dendritic changes. Previous studies have demonstrated that all parvalbuminimmunoreactive neurons in the hippocampus and fascia dentata contain the inhibitory neurotransmitter GABA (17) and that the entorhinal fibers, in addition to contacting principal neurons (18), establish synapses with parvalbuminimmunoreactive cells (19). Thus, our in vivo model enables us to study transneuronal changes in identified postsynaptic elements after entorhinal lesion.…”

GABAergic Cells Are the Major Postsynaptic Targets of Mossy Fibers in the Rat Hippocampus

“…T wo previous electron microscopic studies indicated that the postsynaptic targets of small terminals were smooth dendrites, a known characteristics of several GABAergic cell types (Amaral, 1979;C laiborne et al, 1986). In contrast, other studies suggested that the large mossy terminals contact GABAergic cells both in the hilus and in the CA3 region of the rat (Frotscher, 1985;Ribak and Seress, 1988;Frotscher, 1989;Deller and Léránth, 1990;Léránth et al, 1990;Nitsch et al, 1990;Deller et al, 1994) and the monkey (Seress and Léránth, 1996). This apparent controversy is likely attributable to the difficulty involved in the identification of postsynaptic targets at the light microscopic level and the lack of a reliable marker of presynaptic terminals in most of these studies.…”

CXCR3-Dependent Microglial Recruitment Is Essential for Dendrite Loss after Brain Lesion

“…Their long dendrites extend to the stratum lacunosum-moleculare and to the outer molecular layer of the dentate gyrus (Kosaka et al, 1987;Sloviter, 1989;Nitsch et al, 1990;Gulyas et al, 1993), where they receive synaptic input from entorhinal fibers (Ruth et al, 1982;Zipp et al, 1989). Lesion of the perforant path thus denervates the distal part of their dendrites, resulting in significant and long-lasting loss of these denervated segments Frotscher, 1991, 1993) (Fig.…”