The study aimed to investigate the functional anatomy of the blood-brain barrier (BBB) and its disruption in neurological diseases, evaluating the impact of therapeutic interventions on BBB integrity. Using a combination of trans-endothelial electrical resistance (TEER) measurements, quantitative analysis of tight junction proteins, and endothelial cell morphology assessments, we explored how various neurological disorders affect BBB function. The study revealed significant reductions in TEER values, tight junction protein levels, and endothelial cell integrity in disease models compared to healthy controls. Therapeutic interventions led to partial restoration of these parameters, suggesting that while current treatments can improve BBB function, they do not fully restore it. Molecular mechanisms underlying BBB disruption were identified, supporting the potential for targeted therapies. Novel drug delivery systems demonstrated promise in enhancing drug transport across the BBB. Overall, the study underscores the critical role of BBB integrity in neurological health and highlights the need for continued development of effective therapeutic strategies and drug delivery methods