Abstract
Zebrafish are a popular vertebrate model for human neurological disorders and drug discovery. Although fecundity, breeding convenience, genetic homology and optical transparency have been key advantages, laborious and invasive procedures are required for electrophysiological studies. Using an electrode-integrated microfluidic system, here we demonstrate a novel multichannel electrophysiology unit to record multiple zebrafish. This platform allows spontaneous alignment of zebrafish and maintains, over days, close contact between head and multiple surface electrodes, enabling non-invasive long-term electroencephalographic recording. First, we demonstrate that electrographic seizure events, induced by pentylenetetrazole, can be reliably distinguished from eye or tail movement artifacts, and quantifiably identified with our unique algorithm. Second, we show long-term monitoring during epileptogenic progression in a scn1lab mutant recapitulating human Dravet syndrome. Third, we provide an example of cross-over pharmacology antiepileptic drug testing. Such promising features of this integrated microfluidic platform will greatly facilitate high-throughput drug screening and electrophysiological characterization of epileptic zebrafish.
Highlights
Advances in microfabrication techniques have led to the design of microfluidic devices for the manipulation of small organisms, including zebrafish larvae[18,19,20,21]
Our results demonstrate that an integrated Zebrafish Analysis Platform (iZAP) system can achieve high-throughput, non-invasive, and long-term electrophysiological monitoring in simple vertebrate epilepsy models
Using the iZAP system, spontaneous trapping by swimming from the inlet pool to restraining channels of zebrafish aligned to recording electrodes can be achieved with simple transfer of multiple zebrafish into the loading chamber, and desired individual zebrafish can be retracted back to inlet chamber by pipetting for genotyping, further characterization, or raising to adulthood
Summary
Advances in microfabrication techniques have led to the design of microfluidic devices for the manipulation of small organisms, including zebrafish larvae[18,19,20,21]. Rapid in vivo imaging of zebrafish larvae has been achieved using a fluidic device that briefly restrains larva in a capillary tube in the field of view of a confocal or widefield microscope objective[22] Each of these approaches were designed to isolate a single zebrafish, and were not described as having the capacity to study multiple zebrafish simultaneously or for prolonged monitoring periods e.g., hours to days. Together with integrated custom-built multichannel head-stage amplifiers, surface microelectrodes contacting zebrafish heads continuously monitor multiple EEG signals from multiple zebrafish with high sensitivity and low electrical noise Such long-term non-invasive electrical readout facilitates reliable, robust, statistical analysis of zebrafish electrophysiology and significantly reduces the time and cost required to validate antiepileptic drugs
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
