Gastric Smooth Muscle In Diabetic Rats NPR-A, NPR-B Receptor Expression

Natriuretic peptide receptor (NPR) there are three subtypes:NPR-A, NPR-B, NPR-C. Which NPR-A, NPR-B is the particle-type guanylate cyclase (Particulate guanylate cyclase, pGC) coupling of the single transmembrane protein, natriuretic peptide (natriuretic peptides, NP) and the two receptor GC receptor itself can activate the activity of catalytic GTP into cGMP, and then activate protein kinase-related physiological effects play. Different affinity for NP and various NPR different, showing the relative receptor binding selectivity. ANP, BNP and NPR-A key combination, CNP and NPR-B key combination of cGMP by NPR-A generation capacity of the order of ANP> BNP> CNP, via NPR-B cGMP generation capacity of the order of CNP> ANP> BNP. Studies have shown that the gastrointestinal tract with NP and NPR distribution, and NP can stomach smooth muscle relaxation. The present study shows blood ANP concentrations in diabetic rats, ANP mRNA changes in gastric smooth muscle and gastric smooth muscle in the NPR-A, B expression of atrial natriuretic peptide as a new diabetic gastric motility disorders of gastrointestinal peptides in the role, as prevention and treatment of diabetes, gastric motility disorders provide a theoretical basis.The main results of this paper is as follows:1. Wistar rats were injected STZ 60 (mg/kg), blood glucose concentration was measured more than a week 16.5mmol/L to determine the model was successful. After 4 weeks, body weight measurement model group (205.33±16.21 g, n= 12P <0.05) and the control group (260.51±20.75 g, n= 10) decreased significantly.2. Radioimmunoassay determination of diabetic rats showed that blood concentrations of ANP, plasma ANP concentrations in diabetic rats increased, peaked at 4 weeks.3. Immunohistochemistry using gastric smooth muscle in the NPR-A, B expression showed that normal control group, gastric smooth muscle cells NPR-A, B positive, can be observed scattered brown granules; antral smooth muscle cells in diabetic rats NPR-A, B are positive, and the normal control group NPR-A-positive brown particles have no obvious change, but NPR-B staining significantly deeper.Above results suggest that:1. Diabetic rats increased plasma ANP concentrations.2. Smooth muscle of diabetic rats, compared with normal controls, smooth muscle cells significantly increased NPR-B, but the NPR-A there was no significant change.