Table 2.
Characteristics of mossy cells
| General characteristic | Specific characteristic | Granule cell | Mossy cell | Dentate gyrus interneuron | Refs |
|---|---|---|---|---|---|
| Anatomical characteristics | |||||
| Cell body | Shape | Oval or circle | Diverse | Diverse | 3,6–8,25,26 |
| Size | Small | Usually large | Usually small | ||
| Axon projections and targets | Local | Hilus and CA3 | Hilus | All layers, usually subtype specific | 3,6–8,25,26 |
| Distal | None | Inner molecular layer | Weak | ||
| Contralateral | None | Inner molecular layer | Weak (BCs and HIPP cells) | ||
| Dendrites | Location | Molecular layer | Mostly hilar | Diverse | 3,6–8,25,26 |
| Spines | Dense | Dense, usually thorny | Usually few | ||
| Immunohistochemistry | GluR2 or GluR3 | Yes | Yes | No | 96,142 |
| Calretinin | Yes, in young GCs | Yes, in mice | Yes, but not in all interneurons | 38,39,70,141,143 | |
| CGRP | No | Yes | No | 144 | |
| CART | No | Yes, in human | No | 37 | |
| D2R | No | Yes | Yes, in a rare subtype of interneurons | 59 | |
| CB1R | No | Yes | Yes | 67 | |
| p11 | No | Yes | Yes, in BCs | 119 | |
| Dysbindin 1C | No | Yes | Unclear | 120 | |
| Glucocorticoid type 2 receptor | Yes | Yes | No | 145 | |
| Calbindin | Yes | No | Yes, in a subtype of interneurons | 13,20,126 | |
| Parvalbumin | No | No | Yes, in BCs | 13,20,126 | |
| STEP | No | Yes | Yes, in HIPP cells | 128 | |
| Electrophysiological characteristics | |||||
| Intrinsic | RS, FS or SS? | RS | RS | FS or SS | 7,13,16,17,146,147 |
| Action potential dv/dt | >1 | >1 | ~1 | ||
| AHP | Small | Small | Large | ||
| Time constant | Short | Long | Short | ||
| Sag | No | Some | Some | ||
| SFA | Robust | Some | Weak | ||
| Synaptic | Spontaneous EPSCs | Infrequent, relative to hilar cells | Frequent, large | Variable, usually small and fast | 35,36,55,148,149 |
| Response to trains of >2 Hz PP stimuli | One response occurs per stimulus | Depolarization of the cell occurs during the train and outlasts the train | Variable | 112,150,151 | |
| Response to ACh or DA | Hyperpolarization | Depolarization | Variable (unclear for DA) | 94,132,137 | |
| Other characteristics | |||||
| Developmental origin | Similar to MCs | Similar to GCs | Distinct from MCs and GCs | 152 | |
| Relative vulnerability | Resistant | Vulnerable | Resistant (BCs) or sensitive (HIPP cells) | 7,20,107,126 | |
ACh, acetylcholine; AHP, afterhyperpolarization; BCs, basket cells; CART, cocaine-amphetamine regulating transcript; CB1R; cannabinoid type 1 receptor; CGRP, calcitonin gene-related peptide; DA, dopamine; dv/dt, rate of rise (ratio of decay of an action potential at threshold for spike generation); D2R, dopamine D2 receptor; EPSCs, excitatory postsynaptic currents; FS, fast spiking; GCs, granule cells; GluR2, glutamate receptor type 2; HIPP, hilar cells that project to the terminal zone of the PP; MC, mossy cell; PP, perforant path; RS, regular spiking; Sag, a reduction in a voltage response to a persistent current command; SFA, spike frequency adaptation; SS, slow spiking; STEP, striatum-enriched protein-tyrosine phosphatase.