[Effect of HANS electroacupuncture on the expression of NPY in PAG of heroin addicted rats].

OBJECTIVE: To examine the effects of Han's acupoint and nerve stimulator (HANS) electroacupuncture on the expression of NPY in periaqueductal grey (PAG) of heroin addicted rats. METHODS: Heroin was injected subcutaneously according to the principle of daily increasing dose in rats of experimented group. The ability of special learning and memory were tested by Morris water maze; The expression of NPY in PAG of rat were detected by immunohistochemistry. RESULTS: (1) Escape latency and searching distance in heroin-addiction group were significantly increased compared with those of normal group during the place navigation test (P < 0.05). However, in acupuncture group, escape latency and searching distance was obviously shortened compared with those of heroin-addiction group (P < 0.05). The exploring time and distance of original platform area in proportion to the total distance in heroin-addiction group significantly decreased compared with those of normal group during spatial probe test (P < 0.05). The exploring time and distance of original platform area in proportion to the total distance in acupuncture group was increased compared with those in heroin-addiction group (P < 0.01). (2) The expression of NPY of heroin-addiction group was lower than that in normal group in PAG, while those of acupuncture group was higher than that in the heroin-addiction group (P < 0.05). CONCLUSION: The learning and memory induced by heroin-addiction could be reversed and the expression of NPY in PAG was increased by HANS in rats.

2-[3-[2-[(2S)-2-Cyano-1-pyrrolidinyl]-2-oxoethylamino]-3-methyl-1-oxobutyl]- 1,2,3,4-tetrahydroisoquinoline: a potent, selective, and orally bioavailable dipeptide-derived inhibitor of dipeptidyl peptidase IV.

Dipeptidyl peptidase IV (DPP-IV) inhibitors are expected to become a new type of antidiabetic drugs. Most known DPP-IV inhibitors often resemble the dipeptide cleavage products, with a proline mimic at the P1 site. As off-target inhibitions of DPP8 and/or DPP9 have shown profound toxicities in the in vivo studies, it is important to develop selective DPP-IV inhibitors for clinical usage. To achieve this, a new class of 2-[3-[[2-[(2S)-2-cyano-1-pyrrolidinyl]-2-oxoethyl]amino]-1-oxopropyl]-based DPP-IV inhibitors was synthesized. SAR studies resulted in a number of DPP-IV inhibitors, having IC(50) values of <50 nM with excellent selectivity over both DPP8 (IC(50) > 100 microM) and DPP-II (IC(50) > 30 microM). Compound 21a suppressed the blood glucose elevation after an oral glucose challenge in Wistar rats and also inhibited plasma DPP-IV activity for up to 4 h in BALB/c mice. The results show that compound 21a possesses in vitro and in vivo activities comparable to those of NVP-LAF237 (4), which is in clinical development.