GAL and depressive disorder: In addition to feeding, GAL and related peptides are involved in cardiovascular, respiratory, gastrointestinal and neuroendocrine mechanisms, memory, cognition, osmotic/metabolic homeostasis, reproduction, neural growth, arousal, sleep, injury response as well as in depression, anxiety, epilepsy, diabetes mellitus, inflammatory bowel disease, pain, stroke, cancer, alcohol intake, multiple sclerosis, Alzheimer disease (where upregulation of GAL occurs) and affective behaviour [2,26,31].