Table 1.

General overview of the NPY receptor family

Human receptor	Peptide preference	cDNA cloned (year)	Comments	References
Y1R	PYY ≥ NPY [leu31,pro34]NPY ≫ NPY(13-36)	1992		Larhammar et al (1992); Herzog et al (1992)
Y2R	PYY = NPY = NPY(13-36) ≫ [leu31,pro34]NPY	1995		Bard et al (1995); Gerald et al (1995)
y3R	NPY ≫ PYY	Never	The putative y3R may actually be a multimerization of one or more of the other NPY receptors	Wahlestedt et al (1992); Movafagh et al (2006)
Y4R	PP > PYY > NPY	1995		Rose et al (1995)
Y5R	NPY(2-36) ≥ NPY	1996		Gerald et al (1996); Weinberg et al (1996)
y6R	N/A	1996	The human y6R is a non-functional pseudogene in the 5q31 region of the genome	Gregor et al (1996); Matsumoto et al (1996)

The human Y1 receptor was cloned in 1992 (Herzog et al, 1992; Larhammar et al, 1992). The Y2 and Y4 receptors were first cloned in 1995 (Bard et al, 1995; Gerald et al, 1995; Rose et al, 1995), and the Y5 receptor in 1996 (Gerald et al, 1996; Weinberg et al, 1996). The neuropeptide y3 and y6 receptors have both been hypothesized in humans. The putative y3 receptor may be a multimerization of one or more NPY receptors (Movafagh et al, 2006; Wahlestedt et al, 1992). The y6 receptor is a non-functional pseudogene in humans, located in the 5q31 region of chromosome 5 (Gregor et al, 1996; Matsumoto et al, 1996).