[Leu31,Pro34]-Neuropeptide Y (human, rat)

Neuropeptide Y (NPY) is a 36-amino acid peptide neurotransmitter widely distributed in the central and peripheral nervous systems, with a variety of physiological roles. Among its functions, NPY is involved in the regulation of energy balance, memory processing, and stress response. The peptide operates through different receptor subtypes, with the Y1 and Y2 receptors being the most studied. The analog [Leu31,Pro34]-Neuropeptide Y has been synthesized to better understand the specific roles of these receptor subtypes and has been found to be a selective agonist for the Y1 receptor2.

[Leu31,Pro34]-Neuropeptide Y (NPY) functions primarily through its interaction with the Y1 receptor subtype. This interaction has been shown to cause a transient increase in cytoplasmic free calcium concentrations in human neuroblastoma cells, which is similar to the response observed with native NPY2. In contrast, this analog does not activate Y2 receptors, which are known to bind long C-terminal fragments of NPY4. The specificity of [Leu31,Pro34]-NPY for the Y1 receptor over the Y2 receptor has been demonstrated in various studies, including those using radiolabeled analogs7. The binding of [Leu31,Pro34]-NPY to Y1 receptors is associated with physiological effects such as an increase in blood pressure in anesthetized rats2.

Neuroscience and Neuropharmacology

In the field of neuroscience, [Leu31,Pro34]-NPY has been used to investigate the role of NPY in the central nervous system. For instance, it has been shown to inhibit potassium-stimulated glutamate release in rat hippocampal slices, suggesting a potent inhibitory action of NPY through Y2 receptors on excitatory amino acid release1. This could have implications for conditions with increased NPY synthesis, such as epilepsy.

Gastroenterology

In gastroenterology, [Leu31,Pro34]-NPY has been studied for its effects on gastric lesion formation and gastric secretion. It has been found to decrease basal gastric acid output and protect against restraint-induced gastric mucosal injury, suggesting a role for NPY in the gut through Y1 receptors3.

Cardiovascular Research

In cardiovascular research, the analog has been used to differentiate between pre- and postjunctional actions of NPY, with [Pro34]NPY selectively identifying postjunctional-mediated actions in vivo5.

Pain and Anxiety Research

[Leu31,Pro34]-NPY has been shown to produce analgesic and anxiolytic effects when microinjected into the periaqueductal gray of rats, indicating potential therapeutic applications for pain and anxiety disorders6.

Endocrinology

The peptide has also been implicated in steroidogenesis, with in vitro studies demonstrating that [Leu31,Pro34]-NPY and related peptides can induce a dose-dependent release of aldosterone from rat adrenal capsule/zona glomerulosa preparations10.