Head-mounted central venous access during optical recordings and manipulations of neural activity in mice

Establishing reliable intravenous catheterization in mice with optical implants allows the combination of neural manipulations and recordings with rapid, time-locked delivery of pharmacological agents. Here we present a procedure for handmade jugular vein catheters designed for head-mounted intravenous access and provide surgical and postoperative guidance for improved survival and patency. A head-mounted vascular access point eliminates the need for a back-mounted button in animals already receiving neural implants, thereby reducing sites of implantation. This protocol, which is readily adoptable by experimenters with previous training and experience in mouse surgery, enables repeated fiber photometry recordings or optogenetic manipulation during drug delivery in adult mice that are awake and behaving, whether head fixed or freely moving. With practice, an experienced surgeon requires ~30 min to perform catheterization on each mouse. Altogether, these techniques facilitate the reliable and repeated delivery of pharmacological agents in mouse models while simultaneously recording at high temporal resolution and/or manipulating neural populations. Key points This protocol details how to gain head-mounted access to the bloodstream to easily combine recording and/or manipulation of neuronal activity with the reliable delivery of pharmacological agents. Compared with other drug delivery methods, the intravenous technique explored here eliminates the stress and pain caused by needle pokes. The surgical and postoperative guidance provided in the protocol improves animal survival and catheter patency, increasing the reliability and reproducibility of results. A protocol describing how to implant head-mounted jugular vein catheters in mice. This procedure facilitates systemic drug administration in a variety of experimental settings, including optical recording and manipulation of neuronal activities and behavioral tests.