Somatostatin receptor subtype SSTR2 mediates the inhibition of high-voltage-activated calcium channels by somatostatin and its analogue SMS 201-995.
Somatostatin and its analogue SMS 201-995 inhibit high voltage-activated (HVA) Ca2+ currents in the rat insulinoma cell line RINm5F which stably express cloned human somatostatin receptor subtype 2 (hSSTR2). In contrast, neither somatostatin nor SMS 201-995 suppresses the HVA Ca2+ currents in RINm5F which stably express cloned hSSTR1. These results suggest that somatostatin-induced inhibition of HVA Ca2+ currents is mediated by a specific receptor subtype and that inhibition of calcium influx through HVA Ca2+ channels is one of the mechanisms of SMS 201-995 action on inhibitory processes of hormone secretion and cell proliferation.
Fujii
Y
Y
Division of Molecular Medicine, Chiba University School of Medicine, Japan.
Gonoi
T
T
Yamada
Y
Y
Chihara
K
K
Inagaki
N
N
Seino
S
S
D000818:Animals; D001667:Binding, Competitive; D015220:Calcium Channels / Q000187:drug effects* / Q000378:metabolism; D002460:Cell Line; D005576:Colforsin / Q000494:pharmacology; D000242:Cyclic AMP / Q000096:biosynthesis; D004563:Electrochemistry; D016244:Guanosine 5'-O-(3-Thiotriphosphate) / Q000494:pharmacology; D006801:Humans; D015282:Octreotide / Q000494:pharmacology*; D051381:Rats; D017481:Receptors, Somatostatin / Q000145:classification / Q000187:drug effects / Q000378:metabolism*; D013004:Somatostatin / Q000494:pharmacology*; D010566:Virulence Factors, Bordetella / Q000494:pharmacology
D015220:Calcium Channels; D017481:Receptors, Somatostatin; D010566:Virulence Factors, Bordetella; D005576:Colforsin; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D013004:Somatostatin; D000242:Cyclic AMP; D015282:Octreotide