[Effects of ohmefentanyl on the content of endorphin in pituitary and brain areas of rats].
Ohmefentanyl was first developed in Shanghai Institute of Materia Medica, Chinese Academy of Sciences. It has been known that ohmefentanyl ip caused analgesia at 3 microg/kg, and catalepsy at 15 microg/kg. In the present paper, we studied the relationship of ohmefentanyl-inudced analgesia and catalepsy with the contents of dynorphin-A1-13, dynorphin-B, metenkephalin and beta-endorphin in pituitary and other brain areas of rats. The results of radioimmunoassay showed that in pituitary all the peptides mentioned were reduced at 3 microg/kg and raised at 15 microg/kg in comparison with 3 microg/kg group; in striatum the levels of dynorphin-A1-13 and dynorphin B did not change significantly at 3 microg/kg but increased at 15 microg/kg. The content of net-enkephalin were reduced at analgesia and raised at catalepsy; in spinal cord dynorphin-B and met-enkephalin were increased dose-dependently; in hippocampus and hypothalamus the contents of peptides varied in different ways, depending on the dose of ohmefentanyl and kinds of peptide measured.