Expression of sulfonylurea receptors in rat taste buds.
To test the possibility that a fast-onset promoting agent repaglinide may initiate prandial insulin secretion through the mechanism of cephalic-phase insulin release, we explored the expression and distribution character of sulfonylurea receptors in rat taste buds. Twenty male Wistar rats aged 10 weeks old were killed after general anesthesia. The circumvallate papillae, fungiform papillae and pancreas tissues were separately collected. Immunohistochemical staining was used to detect the expression and distribution of sulfonylurea receptor 1 (SUR1) or sulfonylurea receptor 2 (SUR2) in rat taste buds. Reverse transcriptase polymerase chain reaction (RT-PCR) was used to analyze the expression of SUR1 or SUR2 mRNA. The pancreatic tissues from the same rat were used as positive control. This is the first study to report that SUR1 is uniquely expressed in the taste buds of fungiform papillae of each rat tongue, while the expression of SUR1 or SUR2 was not detected in the taste buds of circumvallate papillae. SUR1 is selectively expressed in rat taste buds, and its distribution pattern may be functionally relevant, suggesting that the rapid insulin secretion-promoting effect of repaglinide may be exerted through the cephalic-phase secretion pathway mediated by taste buds.
Liu
Dian-Xin
DX
Department of Endocrinology, The First Affiliated Hospital of Harbin Medical University, No. 23 Youzheng Street, Nangang District, Harbin 150001, Heilongjiang Province, China.
Liu
Xiao-Min
XM
Zhou
Li-Hong
LH
Feng
Xiao-Hong
XH
Zhang
Xiao-Juan
XJ
D018528:ATP-Binding Cassette Transporters / Q000032:analysis / Q000096:biosynthesis*; D000818:Animals; D007150:Immunohistochemistry; D007328:Insulin / Q000378:metabolism; D008297:Male; D009928:Organ Specificity; D010179:Pancreas / Q000378:metabolism; D024661:Potassium Channels, Inwardly Rectifying / Q000032:analysis / Q000096:biosynthesis*; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D011955:Receptors, Drug / Q000032:analysis / Q000096:biosynthesis*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D064233:Sulfonylurea Receptors; D013650:Taste Buds / Q000378:metabolism*
D018528:ATP-Binding Cassette Transporters; C577509:Abcc8 protein, rat; C577512:Abcc9 protein, rat; D007328:Insulin; D024661:Potassium Channels, Inwardly Rectifying; D012333:RNA, Messenger; D011955:Receptors, Drug; D064233:Sulfonylurea Receptors