This definition appears rarely
See other definitions of HEP
Samples in periodicals archive:
McMillen, BA; Shank, JE; Jordan, KB; Williams, HL; Basile, AS (2007). "Effect of DOV 102,677 on the volitional consumption of ethanol by Myers' high ethanol-preferring rat". Alcoholism, clinical and experimental research 31 (11): 1866–71. doi:10. 1111/j. 1530-0277. 2007.