NPY and anorexia nervosa: AN: Anorexia nervosa; CSF: Cerebrospinal fluid; ND: No difference from healthy controls; Increased: Higher than healthy controls; Decreased: Lower than healthy controls; AGRP: Agouti-related peptide; BDNF: Brain-derived neurotrophic factor; CRH: Corticotropin-releasing hormone; TRH: Thyrotropin-releasing hormone; SRIF: Somatostatin; α-MSH: α-melanocyte-stimulating hormone; NPY: Neuropeptide Y