CRH and Parkinson disease: No recent studies have examined the status of CRF secretion in the PD brain and the literature is limited to one study from decades ago reporting of a reduction in CRF-like immunoreactivity post mortem neocortical PD brain tissue (271), and another which examined correlations of several neuropeptides including CRF in the CSF of idiopathic PD patients but without comparing actual concentrations to the control group (272).