Neuropeptide Y potentiates the luteinizing hormone (LH) response to LH-releasing hormone in men.

It has been demonstrated in several animal species that neuropeptide Y (NPY) exerts a modulatory effect on luteinizing hormone (LH) secretion. However, whether NPY plays a similar role also in humans has yet to be determined. Therefore, in this study we examined the effect of human NPY on the anterior pituitary hormone secretion in 6 normal men. Intravenous bolus injection of 100 micrograms of human NPY alone did not affect the secretion of any anterior pituitary hormone or cortisol. However, when NPY (100 micrograms) was administered simultaneously with LH-releasing hormone (LHRH, 100 micrograms), a significant potentiation was observed for LHRH-induced LH secretion. Similarly, follicle-stimulating hormone (FSH) response to LHRH was slightly potentiated by the coadministration of NPY, although this effect was not statistically significant. This is the first study to demonstrate that NPY can augment the LHRH-induced LH secretion in humans.