van Bogaert P, Soukias Y, Dehaye J P, Lambert M, Poloczek P, Winand J, Mayer R, Christophe J
Regul Pept. 1987 Jun;17(6):339-48. doi: 10.1016/0167-0115(87)90057-7.
Adenylate cyclase activity was stimulated by vasoactive intestinal peptide (VIP) in rat parotid membranes, in the presence of 100 microM guanosine triphosphate (GTP). The threshold concentration of VIP was 300 nM and the activity doubled at the maximal VIP concentration tested (30 microM). The relative potency of peptides of the VIP family was: VIP greater than peptide histidine isoleucinamide (PHI) greater than secretin. The beta-adrenergic agent isoproterenol was a more efficient activator of rat parotid adenylate cyclase and its stimulatory effect, like that of VIP, depended on the presence of GTP. The effects of VIP and isoproterenol were both potentiated by 10 microM forskolin. By comparison with rat parotid preparations, membranes from a human parotid gland responded similarly to the VIP family of peptides (VIP greater than PHI greater than secretin). In both rat and human parotid membranes, two proteins (Mr 44 kDa and 53 kDa) of the alpha-subunit of Ns (the guanyl nucleotide-binding stimulatory protein) were labelled by ADP-ribosylation, in the presence of cholera toxin. Taken together, these results indicate that VIP receptors, when coupled to Ns, were able to activate the adenylate cyclase system in rat and human parotid membranes.
在存在100微摩尔鸟苷三磷酸（GTP）的情况下，血管活性肠肽（VIP）可刺激大鼠腮腺膜中的腺苷酸环化酶活性。VIP的阈值浓度为300纳摩尔，在所测试的最大VIP浓度（30微摩尔）下活性增加一倍。VIP家族肽的相对效力为：VIP＞肽组氨酸异亮酰胺（PHI）＞促胰液素。β-肾上腺素能药物异丙肾上腺素是大鼠腮腺腺苷酸环化酶更有效的激活剂，其刺激作用与VIP一样，依赖于GTP的存在。VIP和异丙肾上腺素的作用均被10微摩尔福司可林增强。与大鼠腮腺制剂相比，人腮腺的膜对VIP家族肽的反应相似（VIP＞PHI＞促胰液素）。在大鼠和人腮腺膜中，在霍乱毒素存在的情况下，Ns（鸟苷酸结合刺激蛋白）的α亚基的两种蛋白质（分子量44 kDa和53 kDa）被ADP-核糖基化标记。综上所述，这些结果表明，VIP受体与Ns偶联时，能够激活大鼠和人腮腺膜中的腺苷酸环化酶系统。
