This protocol describes an optogenetic activation of neuromelanine-laden dopaminergic neurons in the SNc-VTA.

This protocol outlines a method for modulating noradrenergic and dopaminergic neuronal activity in the LC and SNc-VTA, respectively, using Cre-dependent hM3D and hM4D expression. It details stereotactic injection techniques for these chemogenetic tools and the preparation of the J60 agonist for intraperitoneal delivery. Developed for longitudinal studies spanning up to four weeks, the protocol aims to assess neuromelanin's activity-dependent accumulation through daily agonist administration.

The elevated plus maze is a classical test to screen anxiety-like behaviors in laboratory animals.

The open field test is a classical test for the quantification of locomotor activity and anxiety-like behaviors in laboratory animals. This protocol is optimized for mice, and it includes the automatic analysis of their movement by Biobserve Viewer.

The parallel beam test protocol is designed to evaluate the motor coordination of mice. This protocol is designed to assess motor skills, particularly in neurological diseases such as Parkinson's disease.

This protocol describes the setup and execution of the light-dark box test for mice, a behavioral experiment used to assess anxiety-related responses. The protocol involves preparing a light-dark box in a controlled environment, utilizing specific lighting conditions and camera settings for optimal observation and recording.

The Rotarod Test Protocol for Mice assesses their motor coordination and balance. Mice are trained to walk on a rotating rod in a dimly lit environment and then tested for their ability to maintain balance as the rod accelerates from 4 to 40 RPM. The test, repeated thrice with intervals, measures the latency to fall and speed at the fall. This protocol is vital to study neurological disease such as Parkinson disease.

The locomotion test is an open field test in darkness, so it does not aim to measure anxiety, only locomotor activity.