5 years ago

Analgesic and anxiolytic effects of [Leu31,Pro34]-neuropeptide Y microinjected into the periaqueductal gray in rats

Several reports have demonstrated that neuropeptide Y (NPY) is involved in food intake, epilepsy, circadian rhythms, drug seeking, pain and anxiety, and other physiological or pathological conditions. On the other hand, periaqueductal gray (PAG) is a key brain center for modulating pain, anxiety and fear. It is the main structure implicated in integrated defensive behaviors. One such behavior, tonic immobility (TI), resembles fear and is able to induce analgesia. After microinjection of [Leu31,Pro34]-Neuropeptide Y ([Leu31,Pro34]-NPY) into the PAG dorsal (D) or ventrolateral (VL) of adult male Wistar rats, the following parameters were assessed: i) the analgesic effect by means of the tail-flick test (TF), ii) the duration of TI as a passive defensive behavioral response and as an anxiety/fear model (considering both TF and TI as single behaviors), iii) TI-induced analgesia by the combination of TF/TI, and iv) the anxious-like state through the elevated plus maze (EPM), and defensive burying behavior (DBB). The results show that the microinjection of [Leu31,Pro34]-NPY into the PAG produced an analgesic effect (increasing the TF latency); overall decreased the TI duration, which might represent an important anti-fear effect. Moreover, [Leu31,Pro34]-NPY microinjected into the PAG allows for a TI-induced analgesic effect, as well as, a substantial anxiolytic effect (evidenced by the EPM and DBB models). Hence, [Leu31,Pro34]-NPY microinjected into the PAG, especially at 0.47nmol/0.5μL produces both analgesic and anxiolytic effects, in a higher magnitude within ventrolateral area.

Publisher URL: www.sciencedirect.com/science

DOI: S0143417917301440

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.