TABLE 1.

PRIMERS FOR REAL TIME qRT-PCR

Gene	Direction	Sequence	Base pair
OPRM1	S	5′- AGTTCTGTATCCCAACCTCTTCC -3′	60-bp
	AS	5′ - TCTGACGAATTCGAGTGGAG -3′
OPRK1	S	5′ -GGAGAGAATAGTAGCTGTATGT-3′	120-bp
	AS	5′ -AGCAGTACCCTAAAATGATATT-3′
OPRD1	S	5′ - TGCACCTGTGCATCGCGCTGA -3′	141-bp
	AS	5′ - GGCTGAAGCTGCTGGGGTC -3′
GAPDH	S	5′ - AACAGCGACACCCACTCCTC -3′	258-bp
	AS	5′ - GGAGGGGAGATTCAGTGTGGT -3′

AS, anti-sense; OPRD1, δ-opioid receptor; OPRK1, κ- opioid receptor; OPRM1, μ-opioid receptor; S, sense.