Retrograde Direction Research Articles

Analyzing Mitochondrial Transport and Morphology in Human Induced Pluripotent Stem Cell-Derived Neurons in Hereditary Spastic Paraplegia.

Neurons have intense demands for high energy in order to support their functions. Impaired mitochondrial transport along axons has been observed in human neurons, which may contribute to neurodegeneration in various disease states. Although it is challenging to examine mitochondrial dynamics in live human nerves, such paradigms are critical for studying the role of mitochondria in neurodegeneration. Described here is a protocol for analyzing mitochondrial transport and mitochondrial morphology in forebrain neuron axons derived from human induced pluripotent stem cells (iPSCs). The iPSCs are differentiated into telencephalic glutamatergic neurons using well-established methods. Mitochondria of the neurons are stained with MitoTracker CMXRos, and mitochondrial movement within the axons are captured using a live-cell imaging microscope equipped with an incubator for cell culture. Time-lapse images are analyzed using software with "MultiKymograph", "Bioformat importer", and "Macros" plugins. Kymographs of mitochondrial transport are generated, and average mitochondrial velocity in the anterograde and retrograde directions is read from the kymograph. Regarding mitochondrial morphology analysis, mitochondrial length, area, and aspect ratio are obtained using the ImageJ. In summary, this protocol allows characterization of mitochondrial trafficking along axons and analysis of their morphology to facilitate studies of neurodegenerative diseases.

Vascular access cannulation in hemodialysis patients: technical approach.

ABSTRACTIntroduction:The vascular access cannulation technique varies among clinics, and guidelines on vascular access give little importance to cannulation techniques. The objective of this study was to evaluate the cannulation technique and to determine which factors are associated with each detail of the technique.Material and methods:The vascular access cannulation was evaluated in 260 patients undergoing hemodialysis. The type and anatomical location of the vascular access, the cannulation technique, direction, gauge, and distance between needles, besides bevel direction and needle rotation were registered.Results:The arteriovenous fistula was the most frequent vascular access (88%), the most used cannulation technique was area (100%), the needle direction was anterograde in most cases (79.5%), and the mean distance between the tips of needles was 7.57±4.43 cm. For arteriovenous grafts, the proximal anatomical location (brachial artery) and cannulation with 16G needles in anterograde position were more predominant. For arteriovenous fistulas, the distal anatomical location (radial artery) and cannulation through 15G needles were more common. Cannulation of vascular access in retrograde direction was associated with a greater distance between needles (13.2 ± 4.4 vs 6.1 ± 3 cm, p < 0.001). Kt/V was higher when the distance between needles was higher than 5 cm (1.61 ± 0.3 vs. 1.47 ± 0.28, p < 0.01).Conclusions:The vascular access cannulation technique depends on the vascular access characteristics and expertise of cannulators. Clinical trials are required for the formulation of guidelines for vascular access cannulation.

Aortic cannula orientation and flow impacts embolic trajectories: computational cardiopulmonary bypass.

Emboli events are associated with the aortic cannula insertion and final position in the ascending aorta. However, the impact of subtle changes in aortic cannula movement and flow influencing embolic transport throughout the aortic arch is not well understood. The present study evaluated the aortic cannula's outflow and orientation effect on emboli entering the aortic branch arteries. A simplified aortic computational model was anteriorly cannulated in the distal ascending aorta with a 21-French straight aortic cannula, and two orientations were analysed by injecting gaseous and solid emboli at pump flows 2, 3 and 5 L/minute. The first aortic cannula orientation (forward flow cannula) was directed towards the lesser curvature. The second aortic cannula orientation (rear flow cannula) was tilted slightly backwards by 15°, providing flow in the retrograde direction. Forward flow cannula produced a primary arch flow, whereas rear flow cannula produced a secondary arch flow resulting in four times longer emboli arch resident times than forward flow cannula. The rear flow cannula had the highest percentage of gaseous emboli entering the brachiocephalic artery of 8%, 12% and 36% (at 2, 3 and 5 L/minute, respectively). Rear flow cannula provided a positive aortic branch arterial flow at all pump flows, whereas at forward flow cannula, the brachiocephalic artery experienced retrograde flows of -1.0% (3 L/minute) and -4.0% (5 L/minute), with the left common carotid -0.23% (5 L/minute). No significant number of solid emboli entered the aortic branch arteries. This numerical study illustrated distinct trajectory behaviours between gaseous and solid emboli where slight changes in aortic cannula orientation influenced idealised emboli direction with higher pump flows magnifying the effects.

Eighteen years of experience with pediatric nutcracker syndrome: the importance of the conservative approach

Nutcracker syndrome (NS) defines an entity generated by the compression of the left renal vein resulting in venous hypertension, which transmitted in a retrograde direction may cause hematuria, proteinuria, and varicocele. The literature concerning exclusively pediatric patients is very rare. To report the authors' experience with pediatric NS in the last 18 years. This is a retrospective review of the patients followed up in the authors' center with diagnosis of NS based on clinical and imaging tests (ultrasound, computed tomography/magnetic resonance imaging, and phlebography). The primary outcome was the success of the conservative approach in the study patients. A total of 21 patients were diagnosed with NS and followed up for a mean period of 52.3 months (37.1-67.5). The mean age at diagnosis was 11.7 years (9.9-13.4). The most frequent symptom of presentation was hematuria in 16 patients (76.2%), being macroscopic in 75% patients and related to physical exercise in 42.9% patients. Other symptoms were left varicocele in 7 patients (33%) and proteinuria in 6 patients (28.6%). Mild to moderate cases received conservative treatment (change of physical activity, postural hygiene), which achieved resolution of symptoms in 16 patients (76.2%). Five cases (23.8%) finally needed a more aggressive approach. Two (9.5%) of them required endovascular procedures (intravascular stent in the renal vein in 1 case and embolization of the spermatic vein in 1 case); in one (4.8%) of the patients, transposition of the left renal vein and kidney autotransplantation were performed, and 2 (9.5%) of the patients with mild cases required surgical correction of the varicocele. Hematuria, usually macroscopic and related to physical exercise, is the most frequent symptom in pediatric patients with NS. The authors advocate studying the aortomesenteric junction by abdominal ultrasound in patients with varicocele or with intermittent macroscopic hematuria. Diagnosis is based on non-invasive tests; phlebography should be reserved for severe cases that require an interventionist attitude. A long period of conservative treatment is the first approach for pediatric patients with NS.

Chemical Composition of Globular Clusters of Milky Way Subsystems from Gaia DR2 Data

Results of a study of the kinematic and chemical properties of globular clusters of the Milky Way based on data from the Gaia DR2 catalog and meaurements with the Hubble Space Telescope are presented. A new method for dividing globular clusters into Galatic subsystems based on the elements of their Galactic orbits is proposed. Samples of globular clusters belonging to the bar/bulge, thick disk, and halo of the Milky Way are obtained. The mean metallicities of the globular clusters in various subsystems are calculated. The mean metallicities of globular clusters of the thick disk and halo display statistically significant differences. At the same time, no statistically significant differences are present between the mean metallicities of halo globular clusters moving in the direction of rotation of the Galactic disk and those moving in the retrograde direction. This argues against the suggestion that retrograde and prograde globular clusters have different origins.

1686 Laparoscopic-Assisted Endoscopic Submucosal Dissection of Early Gastric Adenocarcinoma

INTRODUCTION: A 69-year-old man underwent esophagogastroduodenoscopy (EGD) a year ago which showed intestinal metaplasia without dysplasia in the gastric antrum and incisura. A repeat EGD showed a single plague in the distal esophagus and erosive gastritis. Biopsies revealed high grade dysplasia (HGD) in the gastric cardia and extensive intestinal metaplasia in the rest of the stomach. A subsequent endoscopic ultrasound and CT imaging of chest, abdomen and pelvis revealed no evidence of extraluminal extension or distant metastasis. Given the tumor location surgical resection would require a total gastrectomy. After consultation with surgical oncology, a decision was made to attempt endoscopic submucosal dissection (ESD) with laparoscopic assistance. CASE DESCRIPTION/METHODS: In this video report, an initial EGD was performed which confirmed a superficial gastric ulcer in the cardia. A laparoscopic gastrotomy with placement of the 15mm laparoscopic port was performed. The endoscope with a cap was introduced through the port directly into the stomach. The lesion in the gastric cardia was visualized in a retrograde direction. ESD was performed using a Dual-J Knife. A 15mm area was resected. The ESD site was examined for any perforation, bleeding or defects and none were noted. Following the endoscopic portion of the procedure, the abdomen was re-insufflated and inspected for signs of perforation and none were found. The gastrotomy was then closed. On gross pathologic examination the gastric cardia specimen measured 1.9 × 1.7 × 0.3 cm. Microscopic examination revealed well differentiated (G1) focal intramucosal adenocarcinoma arising in a background of intestinal metaplasia with HGD. Tumor invaded lamina propria but no invasion of muscularis mucosa was identified. All margins were uninvolved by carcinoma and dysplasia. The final pathologic stage of the resected specimen was pT1a. Given the findings, lymph node disease was determined to be extremely low and less invasive ESD was expected to be curative 1, 2. A follow up EGD 2-months post-procedure showed no evidence of recurrence. DISCUSSION: In conclusion, tumors of the gastric cardia are among the most technically difficult lesions to be removed by ESD with curative rates around 66% 3. This decreases further with tumors located in the anterior hemisphere or have deep submucosal invasion. Laparoscopic assistance provides a head on view for a full thickness ESD. Our case demonstrates this technique is safe and effective. Watch the video: http://bit.ly/2LuEe7N.

Phospholipid middle management.

The Mla phospholipid transporter is a multi-subunit ATP-binding cassette transport system widely understood to move phospholipids in a retrograde direction; that is, from the outer membrane to the inner membrane. However, recent studies reveal that Mla might move phospholipids in the opposite, anterograde direction.

Modelling transport and mean age of dense core vesicles in large axonal arbours.

A model simulating the transport of dense core vesicles (DCVs) in type II axonal terminals of Drosophila motoneurons has been developed. The morphology of type II terminals is characterized by the large number of en passant boutons. The lack of both scaled-up DCV transport and scaled-down DCV capture in boutons results in a less efficient supply of DCVs to distal boutons. Furthermore, the large number of boutons that DCVs pass as they move anterogradely until they reach the most distal bouton may lead to the capture of a majority of DCVs before they turn around in the most distal bouton to move in the retrograde direction. This may lead to a reduced retrograde flux of DCVs and a lack of DCV circulation in type II terminals. The developed model simulates DCV concentrations in boutons, DCV fluxes between the boutons, age density distributions of DCVs and the mean age of DCVs in various boutons. Unlike published experimental observations, our model predicts DCV circulation in type II terminals after these terminals are filled to saturation. This disagreement is likely because experimentally observed terminals were not at steady state, but rather were accumulating DCVs for later release. Our estimates show that the number of DCVs in the transiting state is much smaller than that in the resident state. DCVs travelling in the axon, rather than DCVs transiting in the terminal, may provide a reserve of DCVs for replenishing boutons after a release. The techniques for modelling transport of DCVs developed in our paper can be used to model the transport of other organelles in axons.

Average surface flows before the formation of solar active regions and their relationship to the supergranulation pattern.

Context.The emergence of solar active regions is an important but poorly understood aspect of the solar dynamo.Aims.Knowledge of the flows associated with the rise of active-region-forming magnetic concentrations through the near-surface layers will help determine the mechanisms of active region formation.Methods.We used helioseismic holography and granulation tracking to measure the horizontal flows at the surface that precede the emergence of active regions. We then averaged these flows over about sixty emerging active regions to reduce the noise, selecting active regions that emerge into relatively quiet Sun. To help interpret the results, we constructed a simple model flow field by generating synthetic “emergence locations” that are probabilistically related to the locations of supergranulation-scale convergence regions in the quiet Sun.Results.The flow maps obtained from helioseismology and granulation tracking are very similar (correlation coefficients for single maps around 0.96). We find that active region emergence is, on average, preceded by converging horizontal flows of amplitude about 40 ms−1. The convergence region extends over about 40 Mm in the east-west direction and about 20 Mm in the north-south direction and is centered in the retrograde direction relative to the emergence location. This flow pattern is largely reproduced by a model in which active region emergence occurs preferentially in the prograde direction relative to supergranulation inflows.Conclusions.Averaging over many active regions reveals a statistically significant pattern of near-surface flows prior to emergence. The qualitative success of our simple model suggests that rising flux concentrations and supergranule-scale flows interact during the emergence process.

Generalized Störmer and dynamical behavior of charged particles near magnetic planet

We study the motion of charged dust grains at arbitrary distants from a rotating magnetic planet,we show that the model treated for dipole field is an excellent approximation in most cases for a generalized Stormer problem, But that fundamentally new physics arises with the inclusion of a quadrupolar magnetic term. In particular,the appearence of a new trajectories for different kind of charged dust grains,which are meaningful when the individual and a comparable impact of the co-rotational and gravitational fields is considered.Furthermore,a detailed mathematical treatment of equilibrium state for various phase spaces for charged components in prograde or retrograde rotation direction with analytical solutions for a non linear parametric system.

Nanoresolution real-time 3D orbital tracking for studying mitochondrial trafficking in vertebrate axons in vivo.

We present the development and in vivo application of a feedback-based tracking microscope to follow individual mitochondria in sensory neurons of zebrafish larvae with nanometer precision and millisecond temporal resolution. By combining various technical improvements, we tracked individual mitochondria with unprecedented spatiotemporal resolution over distances of >100 µm. Using these nanoscopic trajectory data, we discriminated five motional states: a fast and a slow directional motion state in both the anterograde and retrograde directions and a stationary state. The transition pattern revealed that, after a pause, mitochondria predominantly persist in the original direction of travel, while transient changes of direction often exhibited longer pauses. Moreover, mitochondria in the vicinity of a second, stationary mitochondria displayed an increased probability to pause. The capability of following and optically manipulating a single organelle with high spatiotemporal resolution in a living organism offers a new approach to elucidating their function in its complete physiological context.

Preserving Mitochondrial Structure and Motility Promotes Recovery of White Matter After Ischemia.

Stroke significantly affects white matter in the brain by impairing axon function, which results in clinical deficits. Axonal mitochondria are highly dynamic and are transported via microtubules in the anterograde or retrograde direction, depending upon axonal energy demands. Recently, we reported that mitochondrial division inhibitor 1 (Mdivi-1) promotes axon function recovery by preventing mitochondrial fission only when applied during ischemia. Application of Mdivi-1 after injury failed to protect axon function. Interestingly, L-NIO, which is a NOS3 inhibitor, confers post-ischemic protection to axon function by attenuating mitochondrial fission and preserving mitochondrial motility via conserving levels of the microtubular adaptor protein Miro-2. We propose that preventing mitochondrial fission protects axon function during injury, but that restoration of mitochondrial motility is more important to promote axon function recovery after injury. Thus, Miro-2 may be a therapeutic molecular target for recovery following a stroke.

Ejaculation Sparing Bladder Neck Incision with Holmium Laser in Patients with Urinary Symptoms and Small Prostates: Short-Term Functional Results

Background: The treatment options for male lower urinary tract symptoms (LUTS) widely range from self-monitoring to oral medications to surgical procedures. As far as concerns surgical treatment of obstructive LUTS, transurethral incision of the prostate is considered as the gold standard in patients with mild benign prostatic enlargement. Objectives: The aim of our study is to describe this novel approach to perform ejaculation sparing Holmium laser bladder neck incision (ES-HoBNI), with particular regard to its effect on ejaculation and LUTS relief. Methods: We evaluated prospective clinical data from 143 consecutive patients who underwent ES-HoBNI at our institution from January 2012 to February 2018. Procedures were performed with a continuous flow 26 Ch resectoscope and a 550 µm holmium laser end-fire fiber. The stenotic bladder neck was deeply incised at 3 and 9’o clock down to the prostatic capsule in a retrograde direction to either side in front of the veromontanum. Results: Median Qmax, postvoid residual volume, International Prostate Symptom Score, and quality of life were 9 mL/s (7.4–10.2), 130 mL (100–190), 15 (13–19), and 3 (2–4), respectively. In total, 110 (76.9) reported regular anterograde ejaculation. Median operative time was 20 min (15–26). Median catheterization time and hospital stay were 3 days (3–4) and 22 h (20–24), respectively. Moreover, we have compared the frequency of anterograde ejaculation, which slightly increases after ES-HoBNI (77 vs. 81.2%) when compared to baseline data, despite not reaching statistical significancy. Conclusions: ES-HoBNI is a safe, reproducible technique to relieve obstructive LUTS in men with small prostates while preserving ejaculation in younger and sexually active individuals.

The potential role of myosin motor proteins in mediating the subcellular distribution of NHE3 in the renal proximal tubule.

Isoform 3 of the Na+/H+ exchanger (NHE3) is responsible for the majority of the reabsorption of NaCl, NaHCO3, and, consequently, water in the renal proximal tubule. As such, this transporter plays an essential role in acid-base balance and extracellular fluid volume homeostasis and determining systemic arterial blood pressure levels. NHE3 activity is modulated by a number of mechanisms, including the redistribution of the transporter between the body of the microvilli (where NHE3 is active) and the base of the microvilli (where NHE3 is less active). Although the physiological, pathophysiological, and pharmacological importance of the subcellular distribution of NHE3 has been well established, the exact mechanism whereby NHE3 is translocated along microvilli microdomains of the proximal tubule apical membrane is unknown. Nonmuscle myosin IIA and unconventional myosin VI move cargoes in anterograde and retrograde directions, respectively, and are known to redistribute along with NHE3 in the proximal tubule in response to a variety of natriuretic and antinatriuretic stimuli, including stimulation or inhibition of the renin-angiotensin system, high dietary Na+ intake, and high blood pressure. Therefore, this review aims to discuss the current evidence that suggests a potential role of myosin IIA and myosin VI in mediating the subcellular distribution of NHE3 along the kidney proximal tubule microvilli and their possible contribution in modifying NHE3-mediated Na+ reabsorption under both physiological and pathophysiological conditions.

Sectoral r modes and periodic radial velocity variations of Sun-like stars

Context. Radial velocity (RV) measurements are used to search for planets orbiting late-type main-sequence stars and to confirm the transiting planets. Aims. The most advanced spectrometers are now approaching a precision of ~10 cm s−1, which implies the need to identify and correct for all possible sources of RV oscillations intrinsic to the star down to this level and possibly beyond. The recent discovery of global-scale equatorial Rossby waves in the Sun, also called r modes, prompted us to investigate their possible signature in stellar RV measurements. These r modes are toroidal modes of oscillation whose restoring force is the Coriolis force; they propagate in the retrograde direction in a frame that co-rotates with the star. The solar r modes with azimuthal orders 3 ≤ m ≲ 15 were identified unambiguously because of their dispersion relation and their long e-folding lifetimes of hundreds of days. Methods. In this paper, we simulate the RV oscillations produced by sectoral r modes with 2 ≤ m ≤ 5 by assuming a stellar rotation period of 25.54 days and a maximum amplitude of the surface velocity of each mode of 2 m s−1. This amplitude is representative of the solar measurements except for the m = 2 mode, which has not yet been observed on the Sun. Results. Sectoral r modes with azimuthal orders m = 2 and 3 would produce RV oscillations with amplitudes of 76.4 and 19.6 cm s−1 and periods of 19.16 and 10.22 days, respectively, for a star with an inclination of the rotation axis to the line of sight i = 60°. Therefore, they may produce rather sharp peaks in the Fourier spectrum of the radial velocity time series that could lead to spurious planetary detections. Conclusions. Sectoral r modes may represent a source of confusion in the case of slowly rotating inactive stars that are preferential targets for RV planet search. The main limitation of the present investigation is the lack of observational constraints on the amplitude of the m = 2 mode on the Sun.

Atypical Fast-Slow Atrioventricular Nodal Reentrant Tachycardia Utilizing a Slow Pathway Extending to the Inferolateral Right Atrium.

Background: The existence of atypical fast-slow (F/S) atrioventricular (AV) nodal reentrant tachycardias (NRT) using slow pathway (SP) variants connected to the right atrial (RA) inferolateral (inf) free wall (FW) along the tricuspid annulus (TA), has been neither confirmed nor precisely characterized. Methods and Results: We studied 7 patients (mean age, 48±16 years; 5 men) with F/S-AVNRT with long RP intervals and an earliest atrial activation at the RA inf-FW along the TA (inf-F/S-AVNRT). AV reentrant tachycardia was excluded on observation of the transition zone criteria in all 7 patients. Atrial tachycardia was excluded on the observation of a V-A-V activation sequence after the induction or entrainment of the tachycardia from the right ventricle in all. During the tachycardia, low-frequency, fractionated potentials (LP) preceding the local atrial electrogram were recorded near the site of the earliest atrial activation in 6 patients. Observations of conduction delay and block of the LP during ventricular entrainment or ablation of the tachycardia indicated that LP reflect retrograde activation via the inf-SP. Retrograde SP conduction was interrupted at the site of earliest atrial activation in 3 patients, and in the right posterior septum in 4 patients. Conclusions: inf-F/S-AVNRT are distinct supraventricular tachycardia incorporating an SP variant connected to the RA inf-FW along the TA in the retrograde direction, which were eliminated by ablation.

Three laparotomies later: extrinsic duodenal atresia from malrotation complicated by intrinsic duodenal and pyloric windsock webs

Abstract We present a term infant with the unusual findings of malrotation in combination with both duodenal and pyloric webs of windsock type, thus masquerading as postoperative bowel dysfunction and ultimately requiring three laparotomies. To the best of our knowledge these three findings in combination have not been previously reported. The dilemma of whether to perform a duodenotomy or not during malrotation repair and the importance of instrumenting the intestine from the duodenotomy site in both retrograde and antegrade directions are discussed.

NO as a multimodal transmitter in the brain: discovery and current status.

NO operates throughout the brain as an intercellular messenger, initiating its varied physiological effects by activating specialized GC-coupled receptors, resulting in the formation of cGMP. In line with the widespread expression of this pathway, NO participates in numerous different brain functions. This review gives an account of the discovery of NO as a signalling molecule in the brain, experiments that originated in the search for a mysterious cGMP-stimulating factor released from central neurones when their NMDA receptors were stimulated, and summarizes the subsequent key steps that helped establish its status as a central transmitter. Currently, various modes of operation are viewed to underlie its diverse behaviour, ranging from very local signalling between synaptic partners (in the orthograde or retrograde directions) to a volume-type transmission whereby NO synthesized by multiple synchronous sources summate spatially and temporally to influence intermingled neuronal or non-neuronal cells, irrespective of anatomical connectivity. LINKED ARTICLES: This article is part of a themed section on Nitric Oxide 20 Years from the 1998 Nobel Prize. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.2/issuetoc.

Bacterial leakage and marginal adaptation of various bioceramics as apical plug in open apex model.

The aim of the present study was to investigate bacterial leakage and marginal adaptation of bioceramic apical plugs. Extracted human mandibular premolars were prepared to simulate open apex using No. 4 Peeso reamer in retrograde direction. In total, 150 specimens were divided into 10 groups by obturation with five bioceramics in two thicknesses. Groups 1, 3, 5, 7, and 9 were obturated with ProRootMTA, Biodentine, TotalFill BC RRM paste, TotalFill BC RRM putty, and RetroMTA at 3mm, and groups 2, 4, 6, 8, and 10 were obturated with the same materials at 4mm. Ten specimens in each group were evaluated for bacterial leakage of Enterococcus faecalis for 75days. Five specimens from each group were sectioned to investigate the gap area under scanning electron microscope. The 3- and 4-mm Biodentine and TotalFill BC RRM putty groups and the 4-mm ProRootMTA group exhibited less bacterial leakage and lower mean percentage of gap area than those of the other groups. TotalFill BC RRM paste showed the highest leakage for both the 3- and 4-mm groups. The 3- and 4-mm Biodentine and TotalFill BC RRM putty groups and the 4-mm ProRootMTA group exhibited the best sealing ability and marginal adaptation of apical plugs.

Development of an Acute Method to Deliver Transgenes Into the Brains of Adult Xenopus laevis.

The central vocal pathway of the African clawed frog, Xenopus laevis, is a powerful vertebrate model to understand mechanisms underlying central pattern generation. However, fast and efficient methods of introducing exogenous genes into the neurons of adult X. laevis are currently not available. Here, we systematically tested methods of transgene delivery into adult X. laevis neurons. Although successfully used for tadpole neurons for over a decade, electroporation was not efficient in transfecting adult neurons. Similarly, adeno-associated virus (AAV) was not reliable, and lentivirus (LV) failed to function as viral vector in adult Xenopus neurons. In contrast, vesicular stomatitis virus (VSV) was a fast and robust vector for adult X. laevis neurons. Although toxic to the host cells, VSV appears to be less virulent to frog neurons than they are to mice neurons. At a single cell level, infected neurons showed normal physiological properties up to 7 days post infection and vocal circuits that included infected neurons generated normal fictive vocalizations up to 9 days post infection. The relatively long time window during which the physiology of VSV-infected neurons can be studied presents an ideal condition for the use of optogenetic tools. We showed that VSV does not gain entry into myelinated axons, but is taken up by both the soma and axon terminal; this is an attractive feature that drives transgene expression in projection neurons. Previous studies showed that VSVs can spread across synapses in anterograde or retrograde directions depending on the types of glycoprotein that are encoded. However, rVSV did not spread across synapses in the Xenopus central nervous system. The successful use of VSV as a transgene vector in amphibian brains not only allows us to exploit the full potential of the genetic tools to answer questions central to understanding central pattern generation, but also opens the door to other research programs that focus on non-genetic model organisms to address unique questions.