Patch-clamp study of neurons and glial cells in isolated myenteric ganglia

2000 ◽  
Vol 278 (4) ◽  
pp. G644-G651 ◽  
Author(s):  
M. Hanani ◽  
M. Francke ◽  
W. Härtig ◽  
J. Grosche ◽  
A. Reichenbach ◽  
...  
Keyword(s):  
Patch Clamp ◽  
Glial Cells ◽  
Muscle Layer ◽  
Membrane Receptors ◽  
Delayed Rectifier ◽  
Longitudinal Muscle Layer ◽  
Inward Currents ◽  
Morphological Identity ◽  
Clamp Study ◽  
Myenteric Ganglia

Most of the physiological information on the enteric nervous system has been obtained from studies on preparations of the myenteric ganglia attached to the longitudinal muscle layer. This preparation has a number of disadvantages, e.g., the inability to make patch-clamp recordings and the occurrence of muscle movements. To overcome these limitations we used isolated myenteric ganglia from the guinea pig small intestine. In this preparation movement was eliminated because muscle was completely absent, gigaseals were obtained, and whole cell recordings were made from neurons and glial cells. The morphological identity of cells was verified by injecting a fluorescent dye by micropipette. Neurons displayed voltage-gated inactivating inward Na+ and Ca2+currents as well as delayed-rectifier K+ currents. Immunohistochemical staining confirmed that most neurons have Na+ channels. Neurons responded to GABA, indicating that membrane receptors were retained. Glial cells displayed hyperpolarization-induced K+ inward currents and depolarization-induced K+ outward currents. Glia showed large “passive” currents that were suppressed by octanol, consistent with coupling by gap junctions among these cells. These results demonstrate the advantages of isolated ganglia for studying myenteric neurons and glial cells.

Atypical localization of myenteric ganglia in the human appendical wall: a comparative study with animal appendix

Biologia ◽  
2014 ◽  
Vol 69 (7) ◽  
Author(s):  
Eliska Kubikova ◽  
Ivana Sivakova ◽  
Anna Perzelova
Keyword(s):  
Myenteric Plexus ◽  
Animal Studies ◽  
Muscle Layer ◽  
Longitudinal Muscle Layer ◽  
Neuronal Marker ◽  
Irregular Pattern ◽  
Human Appendix ◽  
Atypical Localization ◽  
Myenteric Ganglia

AbstractThe presence of well developed appendices in some animals when compared to humans has led to speculation that appendix is a vestigial organ. Increasing number of studies have revealed that the appendix serves as an important organ in humans. The function of animal appendix, and the differences between species remain poorly understood. In this study we examined human myenteric plexus and compared them with animal studies. Appendices were obtained from five young adults in which the appendix was found to be normal after removal. Fixed appendix cryosections were examined by immunofluorescence methods using neuronal marker antibodies to neurofilaments and beta III tubulin. Both antibodies stained myenteric ganglia which were arranged in an apparently irregular pattern in human appendix wall. We observed unexpected localization of myenteric ganglia in the subserosa often accompanied by rarely occurring ganglia in the longitudinal muscle layer. These ganglia were of different sizes and shapes and unequally distributed under a thin layer of serosa. Our findings raise many questions about the possible role of irregular and atypical myenteric ganglia localization in relation to altered motility and subsequent pathogenesis of the appendix in inflammatory disease in humans. On the other hand, studies of the literature have revealed simplicity in the organization of myenteric plexus, e.g., in well-developed rabbit appendix. In addition, appendicitis in animals is restricted to in apes with similarly shaped appendix to humans.

scholarly journals Patch-clamp analysis of voltage-activated and chemically activated currents in the vomeronasal organ of Sternotherus odoratus (stinkpot/musk turtle)

2001 ◽  
Vol 204 (24) ◽  
pp. 4199-4212
Author(s):  
D. A. Fadool ◽  
M. Wachowiak ◽  
J. H. Brann
Keyword(s):  
Patch Clamp ◽  
Response Spectrum ◽  
Vomeronasal Organ ◽  
Input Resistance ◽  
Resting Potential ◽  
Sternotherus Odoratus ◽  
Female Urine ◽  
Inward Currents ◽  
K Current ◽  
Clamp Study

SUMMARY The electrophysiological basis of chemical communication in the specialized olfactory division of the vomeronasal (VN) organ is poorly understood. In total, 198 patch-clamp recordings were made from 42 animals (Sternotherus odoratus, the stinkpot/musk turtle) to study the electrically and chemically activated properties of VN neurons. The introduction of tetramethylrhodamine-conjugated dextran into the VN orifice permitted good visualization of the vomeronasal neural epithelium prior to dissociating it into single neurons. Basic electrical properties of the neurons were measured (resting potential, –54.5±2.7 mV, N=11; input resistance, 6.7±1.4 GΩ, N=25; capacitance, 4.2±0.3 pF, N=22; means ± s.e.m.). The voltage-gated K+ current inactivation rate was significantly slower in VN neurons from males than in those from females, and K+ currents in males were less sensitive (greater Ki) to tetraethylammonium. Vomeronasal neurons were held at a holding potential of –60 mV and tested for their response to five natural chemicals, female urine, male urine, female musk, male musk and catfish extract. Of the 90 VN neurons tested, 33 (34 %) responded to at least one of the five compounds. The peak amplitude of chemically evoked currents ranged from 4 to 180 pA, with two-thirds of responses less than 25 pA. Urine-evoked currents were of either polarity, whereas musk and catfish extract always elicited only inward currents. Urine applied to neurons harvested from female animals evoked currents that were 2–3 times larger than those elicited from male neurons. Musk-evoked inward currents were three times the magnitude of urine- or catfish-extract-evoked inward currents. The calculated breadth of responsiveness for neurons presented with this array of five chemicals indicated that the mean response spectrum of the VN neurons is narrow (H metric 0.11). This patch-clamp study indicates that VN neurons exhibit sexual dimorphism in function and specificity in response to complex natural chemicals.

Patch clamp study on primary culture of isolated proximal convoluted tubules

1988 ◽  
Vol 413 (1) ◽  
pp. 51-61 ◽  
Author(s):  
J. Merot ◽  
M. Bidet ◽  
B. Gachot ◽  
S. Le Maout ◽  
M. Tauc ◽  
...  
Keyword(s):  
Patch Clamp ◽  
Primary Culture ◽  
Clamp Study ◽  
Convoluted Tubules ◽  
Proximal Convoluted Tubules
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