Objective To investigate the role pituitary adenylate cyclase-activating polypeptide (PACAP) in the growth modulation of PACAP of human pancreas carcinoma cells and determine whether sphingomyolin (SM) may act as a second messenger involved in the postreceptor signal transduction. Methods Human pancreas carcinoma cell strains, JF305, HS766T and ASPC-1 cells were cultivated, reproduced and then treated with PACAP1-38 (10- 12 - 10- 6 M). The amounts of proliferated carcinoma cells were estiimated with Mosmann's method (MTT). The concentrations of intracellular SM in cells were determined with thin layer chromotograph. Intracellular adenosine monophosphate and Ca2 + levels were detected by radioimmunoassay and Fura-2/AM respectively. ResultsIt was found that three kind of human pancreatic cancer cells were proliferated and the intracellular levels of SM, cAMP and cytosolic Ca2+ were increased by treating PACAP1-38. The effect of PACAP1-38 in JF305, HS766T and ASPC-1 could be inhibited by Somatostatin.ConclusionPACAP1-38 may play a role in the proliferation of human pancreatic cancer cells. The postreceptorsignal transduction of PACAP may be mediated by both adenosine cyclinase and Calcium-calmodin pathways. SM may be a second messenger involved in this process.

Objective To investigate the role pituitary adenylate cyclase activating polypeptide (PACAP) in the growth modulation of PACAP of human pancreas carcinoma cells and determine whether sphingomyolin (SM) may act as a second messenger involved in the postreceptor signal transduction. Methods Human pancreas carcinoma cell strains, JF305, HS766T and ASPC 1 cells were cultivated, reproduced and then treated with PACAP 1 38 (10 -12 -10 -6 M). The amounts of proliferated carcinoma cells were estiimated with Mosmann's method (MTT). The concentrations of intracellular SM in cells were determined with thin layer chromotograph. Intracellular adenosine monophosphate and Ca 2+ levels were detected by radioimmunoassay and Fura 2/AM respectively. Results It was found that three kind of human pancreatic cancer cells were proliferated and the intracellular levels of SM, cAMP and cytosolic Ca 2+ were increased by treating PACAP 1 38 . The effect of PACAP 1 38 in JF305, HS766T and ASPC 1 could be inhibited by Somatostatin. Conclusion PACAP 1 38 may play a role in the proliferation of human pancreatic cancer cells. The postreceptorsignal transduction of PACAP may be mediated by both adenosine cyclinase and Calcium calmodin pathways. SM may be a second messenger involved in this process.

OBJECTIVETo understand the mutational patterns and mechanism of short tandem repeats(STRs).

METHODSThe DNA samples of 19 parent-child pairs with mutations in three loci (FGA, D12S391, and D11S554) were genotyped by silver staining on STR. Alleles to be sequenced were excised from gels, reamplified by PCR, and purified. Sequencing was performed by use of cycle sequencing.

RESULTSThere were 18 out of 19 pedigrees in which the 'new' alleles gained or lost a single repeat (8 gains, 7 losses, and 3 being indistinguishable). Only one pedigree lost two repeats. In the 19 pedigrees, there were 13 pedigrees whose 'new' alleles came from fathers, 3 from mothers, 3 from either father or mother. The ratio was 4 1 between fathers and mothers. The mutation of three STR loci occurred in the long, uninterrupted tetranucleotide repeat regions ('CTTT' in FGA, 'AGAT' in D12S391, and 'AAAG' in D11S554).

CONCLUSIONSingle- step mutations accounted for 95% of STR mutation events in these three loci: FGA, D12S391, and D11S554. The rest were double step mutations. There was no insertion or deletion of an incomplete repeat in any of the pedigrees. The mutation was mainly caused by fathers. The long, uninterrupted tetranucleotide repeats in these three loci might be susceptible to mutation.

Alleles ; Base Sequence ; DNA ; chemistry ; genetics ; DNA Mutational Analysis ; Female ; Gene Frequency ; Genotype ; Humans ; Male ; Microsatellite Repeats ; genetics ; Mutation ; Nuclear Family ; Tandem Repeat Sequences ; genetics