Dye Coupling and Immunostaining of Astrocyte-Like Glia Following Intracellular Injection of Fluorochromes in Brain Slices of the Grasshopper, Schistocerca gregaria

The cells of Necturus gallbladder epithelium are electrically coupled. This work used intracellular injection of the fluorescent dye Lucifer yellow to demonstrate that these cells are also dye coupled and that this coupling is rapidly and reversibly inhibited by high concentrations of carbon dioxide. Dye coupling is also inhibited by the calcium ionophore A23187.

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Dendritic Projections and Dye-Coupling in Dopaminergic Neurons of the Substantia Nigra Examined in Horizontal Brain Slices From Young Rats

Journal of Neurophysiology ◽

10.1152/jn.00020.2003 ◽

2003 ◽

Vol 90 (4) ◽

pp. 2531-2535 ◽

Cited By ~ 14

Author(s):

John Y. Lin ◽

Michiel van Wyk ◽

Tharushini K. Bowala ◽

Min-Yau Teo ◽

Janusz Lipski

Keyword(s):

Substantia Nigra ◽

Dopaminergic Neurons ◽

Lucifer Yellow ◽

Brain Slices ◽

Positive Control ◽

Substantia Nigra Pars Compacta ◽

Dye Coupling ◽

Whole Cell ◽

Connexin 36

We examined the rostro-caudal dendritic spread of striatally projecting dopaminergic neurons of the Substantia Nigra pars compacta (SNc) and investigated the presence of dye-coupling after labeling these cells with a mixture of lucifer yellow (LY) and neurobiotin (NB) or with LY alone. Whole cell recordings were made from horizontal brain slices (400 μm) obtained from P5-P20 rats. SNc neurons retrogradely labeled with Fluoro-Gold and located in the region containing tyrosine hydroxylase-immunoreactive cells displayed Ih current and other properties characteristic of SNc neurons. To prevent extracellular leakage, dyes were introduced into patch pipettes after the establishment of whole cell configuration, and cells were filled under visual control. In contrast to previous studies conducted in coronal sections that identified dendritic projections of SNc neurons mainly in the medio-lateral and ventral directions, almost all neurons labeled in our study (53/54) additionally displayed a large rostro-caudal dendritic span (649 ± 219 μm). Dye-coupling between SNc neurons was not observed under basal conditions, in the presence of gap junction “openers” (forskolin, trimethylamine), or after neurons were filled with LY using sharp intracellular microelectrodes. As a “positive control,” dye-coupling was demonstrated in four hippocampal dentate gyrus neurons that were filled using the same patch pipette technique. In addition, none of the tested SNc cells ( n = 12) showed expression of connexin 36 (the “neuronal” connexin) when tested with single-cell RT-PCR. In conclusion, this study revealed extensive rostro-caudal dendritic projections of SNc neurons. Under our in vitro conditions, no evidence was found for dye-coupling among these neurons.

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Patterns of dye coupling involving serotonergic neurons provide insights into the cellular organization of a central complex lineage of the embryonic grasshopper Schistocerca gregaria

Development Genes and Evolution ◽

10.1007/s00427-010-0348-y ◽

2010 ◽

Vol 220 (11-12) ◽

pp. 297-313 ◽

Cited By ~ 5

Author(s):

George Boyan ◽

Bertram Niederleitner

Keyword(s):

Schistocerca Gregaria ◽

Central Complex ◽

Cellular Organization ◽

Dye Coupling ◽

Serotonergic Neurons

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Role of Connexin 36 in Autoregulation of Oxytocin Neuronal Activity in Rat Supraoptic Nucleus

ASN NEURO ◽

10.1177/1759091419843762 ◽

2019 ◽

Vol 11 ◽

pp. 175909141984376 ◽

Cited By ~ 3

Author(s):

Ping Wang ◽

Stephani C. Wang ◽

Dongyang Li ◽

Tong Li ◽

Hai-Peng Yang ◽

...

Keyword(s):

Neuronal Activity ◽

Supraoptic Nucleus ◽

Brain Slices ◽

Virgin Female ◽

Female Rats ◽

Dye Coupling ◽

Connexin 36 ◽

Postsynaptic Currents ◽

Junctional Communication ◽

Vasopressin Neurons

In the supraoptic nucleus (SON), the incidence of dye coupling among oxytocin (OT) neurons increases significantly in nursing mothers. However, the type(s) of connexin (Cx) involved is(are) unknown. In this study, we specifically investigated whether Cx36 plays a functional role in the coupling between OT neurons in the SON of lactating rats. In this brain region, Cx36 was mainly coimmunostained with vasopressin neurons in virgin female rats, whereas in lactating rats, Cx36 was primarily colocalized with OT neurons. In brain slices from lactating rats, application of quinine (0.1 mM), a selective blocker of Cx36, significantly reduced dye coupling among OT neurons as well as the discharge/firing frequency of spikes/action potentials and their amplitude, and transiently depolarized the membrane potential of OT neurons in whole-cell patch-clamp recordings. However, quinine significantly reduced the amplitude, but not frequency, of inhibitory postsynaptic currents in OT neurons; the duration of excitatory postsynaptic currents was reduced but not their frequency and amplitude. Furthermore, the excitatory effect of OT (1 pM) on OT neurons was significantly weakened and delayed by quinine, and burst firing was absent in the presence of this inhibitor. Lastly, Western blotting analysis revealed that the presence of combined, but not alone, quinine and OT significantly reduced the amount of Cx36 in the SON. Thus, Cx36-mediated junctional communication plays a crucial role in autoregulatory control of OT neuronal activity, likely by acting at the postsynaptic sites. The level of Cx36 is modulated by its own activity and the presence of OT.

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