Acute and Chronic Effects of GLP-1 Receptor Agonist Liraglutide on the Sprague Dawley Rat Neurointermediate Lobe Proteome and Phosphoproteome

ABSTRACT: Obesity and its co-morbidities, such as diabetes and hypertension, can significantly reduce a person’s quality of life and place huge pressure on healthcare resources. When we eat a meal our gut and brain release hormones to control the amount of food and fluid we ingest to prevent overeating. One of these hormones is called glucagon-like peptide 1 (GLP-1) and is released from intestinal cells in response to food intake but also produced and released in the brain. Drug analogues of GLP-1 are already successfully in use in the clinic to treat both diabetes and obesity. The aim of this work was to extend our earlier phosphoproteomic findings about interactions of GLP-1 receptor agonist liraglutide, a drug that is approved for diabetes and obesity treatment in humans, with the neurointermediate lobe (posterior pituitary + intermediate lobe). This work focussed on the proteome and phosphoproteome of the neurointermediate lobe of the male and female rat pituitary gland. Liraglutide (Tocris, 6517/1) was prepared in normal saline to a concentration of 100 μg/ml. Injections of 100 μg/kg body weight or normal saline vehicle were performed intraperitoneally using a 30-gauge insulin syringe. Acute study - Animals were housed singly for 4 weeks before experimentation. Injections were performed during the final 30 minutes of the light phase before the lights went off. Animals were killed 4-5 hours (n = 6 animals per group) after injection of liraglutide or vehicle. Chronic study - Animals were singly housed for 2 weeks prior to experimentation. Injections were performed daily for 14 days during the final 30 minutes of the light phase before the lights went off. Animals were killed 4-5 hours (n = 6 animals per group) after the final injection of liraglutide or vehicle.

INSTRUMENT(S):

ORGANISM(S): Rattus Norvegicus (rat)

TISSUE(S): Neurohypophysis

SUBMITTER: Michael Greenwood  

LAB HEAD: Michael Paul Greenwood

PROVIDER: PXD068252 | Pride | 2026-06-26

REPOSITORIES: Pride