Neural regulation and spontaneous constrictions of microvessels in the stomach

2016 Fiscal Year Final Research Report

• Project/Area Number: 26860521
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Gastroenterology
• Research Institution: Nagoya City University
• Principal Investigator: MITSUI Retsu 名古屋市立大学, 大学院医学研究科, 講師 (90434092)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 血管平滑筋 / 平滑筋 / 微小血管 / 自発収縮 / 自律神経 / 細静脈 / 細動脈 / 内皮細胞

Outline of Final Research Achievements

The venular mural cells (vascular smooth muscle cells and pericytes) connected each other via gap junctions in the stomach periodically exhibited synchronous, spontaneous rise in intracellular Ca2+ concentration followed by the rhythmic spontaneous constrictions of venules. These activities depended on both spontaneous Ca2+ release from intracellular Ca2+ store and L-type Ca2+ channel-mediated Ca2+ influx. Although endothelial nitric oxide (NO) potentially inhibited spontaneous constrictions, the cGMP degrading enzyme phosphodiesterase 5 (PDE5) continuously inhibited NO-cGMP signalling in mural cells to maintain spontaneous constrictions. The spontaneous constrictions may prevent blood stagnation during prolonged gastric wall distension by ingested food. On the other hand, a sympathetic nerve-mediated sustained venular constriction may be important for acutely draining blood from the gastrointestinal tract to other organs such as the heart and brain during exercise or haemorrhage.

Free Research Field

生理学、形態学