Of the 11 families, PDE4, PDE7 and PDE8 selectively deactivate cAMP [6,7], with PDE4 receiving considerable experimental attention in animal models of various neurological conditions, including affective disorders [8,9,10], neuroinflammation following injury [11], cognitive impairment/dementia [12,13,14,15], neurodegenerative diseases such as Alzheimer’s, Parkinson’s and Huntington’s diseases [16,17,18], schizophrenia [19] and substance use disorders, including psychostimulant use disorder [20,21,22,23,24] and AUD c.f., [3]. The gene discussed is PDE4A; the disease is Parkinson disease.