Neuroscience

The organ of Corti, located in the inner ear, is the primary organ responsible for animal hearing. Each hair cell has a V-shaped or U-shaped hair bundle composed of actin-filled stereocilia and a kinocilium supported by true transport microtubules. Damage to these structures due to noise exposure, drug toxicity, aging, or environmental factors can lead to hearing loss and other disorders. The challenge when examining auditory organs is their location within the bony labyrinth and their small and fragile nature. This protocol describes the dissection procedure for the cochlear organ, followed by confocal imaging of immunostained endogenous and fluorescent proteins. This approach can be used to understand hair cell physiology and the molecular mechanisms required for normal hearing.

The neuromuscular junction (NMJ) is an interface between motor neurons and skeletal muscle fibers, facilitating the transmission of signals that initiate muscle contraction. Its pivotal role lies in ensuring efficient communication between the nervous system and muscles, allowing for precise and coordinated movements essential for everyday activities and overall motor function. To provide insights into neuromuscular disease and development, understanding the physiology of NMJ is essential. We target acetylcholine receptors (AChR) by immunofluorescence assay (IFA) with α-bungarotoxin (BTX; snake venom neurotoxins binding to AChR) to visualize and quantify the NMJ. Changes in AChR distribution or structure can indicate alterations in receptor density, which may be associated with neuromuscular disorders or conditions that affect synaptic transmission. This protocol provides the methodology for isolating and longitudinally sectioning gastrocnemius muscle for AChR-targeted IFA for confocal microscopy and performing quantitative analysis of NMJs.