Inhibition of PACAP activity by a receptor antagonist results in changes in cell cycle and apoptotic proteins in chick neuroblasts.

We showed previously that early chick neuroblasts stop proliferating and undergo apoptosis when deprived of endogenous pituitary adenylate cyclase-activating polypeptide (PACAP). To identify proteins involved in these processes, we blocked the primary PACAP receptor and determined protein changes using isotope-coded affinity tag (ICAT) analysis. Cell cycle exit was characterized by a decrease in proteins regulating ribosome biogenesis and protein translation.

PACAP maintains cell cycling and inhibits apoptosis in chick neuroblasts.

We previously reported that pituitary adenylate cyclase-activating polypeptide (PACAP) increased cAMP in neuroblast-enriched cultures from embryonic day 3.5 chick brain. Also, the neuroblasts expressed the mRNA, peptide, and receptor for PACAP.

Early expression of pituitary adenylate cyclase-activating polypeptide and activation of its receptor in chick neuroblasts.

To investigate the involvement of pituitary adenylate cyclase- activating polypeptide (PACAP) and GH-releasing factor (GRF) during early chick brain development, we established neuroblast- enriched primary cell cultures derived from embryonic day 3.5 chick brain. We measured increases in cAMP generated by several species-specific forms of the peptides.

In vitro oxime-induced reactivation of various molecular forms of soman-inhibited acetylcholinesterase in striated muscle from rat, monkey and human.

The purpose of this study was to compare the in vitro reactivation of the various molecular forms of soman-inhibited acetylcholinesterase by oximes such as HI-6, toxogonin and PAM, in striated muscle tissue from three species-rat, monkey and human. To simulate the various in vivo conditions the oxime was present either 5 min before and after (Pre-Post) or 5 min after (Post) exposure to the nerve agent soman. In the Pre-Post mode the oxime effects would result from a combination of not only shielding of acetylcholinesterase from soman inhibition but also from immediate reactivation of soman-inhibited acetylcholinesterase.