Table 1

Ability of [dPhe6,βAla11,Phe13,Nle14]Bn(6-14), GRP and NMB to alter [3H]IP in NCI-N417 and NCI-H720 cells in the presence or absence of a hGRP receptor antagonist

Peptide AddedTotal [3H]IP (Exp/Con)
NCI-N417 100 nM [dPhe6]Bn(6-13)MENCI-H720 100 nM [dPhe6]Bn(6-13)ME
AbsentPresentAbsentPresent
[dPhe6,βAla11,Phe13,Nle14]Bn(6-14)
 10 nM1.58  ± 0.161-a 1.73  ± 0.261-a 1.69  ± 0.10a,e 1.38  ± 0.121-a
 1000 nM2.38  ± 0.27a,d 2.20  ± 0.401-a 1.92  ± 0.121-a 1.71  ± 0.171-a
GRP
 10 nM0.96  ± 0.051.06  ± 0.071.36  ± 0.10a,e 1.04  ± 0.09
 1000 nM1.00  ± 0.060.98  ± 0.021.67  ± 0.08a,c,e 1.37  ± 0.07a,d
NMB
 10 nM0.96  ± 0.051.07  ± 0.031.09  ± 0.050.94  ± 0.07
 1000 nM0.98  ± 0.051.02  ± 0.091.29  ± 0.21b,e 0.92  ± 0.03

NCI-N417 and NCI-H720 cells were incubated with GRP, NMB or [dPhe6,βAla11,Phe13,Nle14]Bn(6-14) at the indicated concentrations for 45 min in the presence or absence of the hGRP receptor antagonist [dPhe6]Bn(6-13)methyl ester (ME). Results are expressed as the ratio of total [3H]IP released in the presence of peptide (Exp) to that released in the absence of peptide (Con). Each value represents the means ± S.E. of at least four experiments performed in duplicate. The control values in NCI-N417 and NCI-H720 cells were 510 ± 72 and 304 ± 26 dpm, respectively. The values with 1 μM [dPhe6,βAla11,Phe13,Nle14]Bn(6-14) were 1187 ± 193 and 586 ± 64 dpm for the NCI-N417 and NCI-H720 cells, respectively.

  • ↵1-a Significantly greater (P < .01) than untreated cells.

  • 1-b Significantly greater (P < .05) than untreated cells.

  • 1-c Significantly greater (P < .01) than 10 nM same peptide.

  • 1-d Significantly greater (P < .05) than 10 nM same peptide.

  • 1-e Significantly greater (P < .05) than same dose of peptide treated with [dPhe6]Bn(6-13)ME.