Cochin University of Science and Technology

About: Cochin University of Science and Technology is a education organization based out in Kochi, Kerala, India. It is known for research contribution in the topics: Thin film & Natural rubber. The organization has 5382 authors who have published 7690 publications receiving 103827 citations. The organization is also known as: CUSAT & Cochin University.

Increased Insulin Secretion by Muscarinic M1 and M3 Receptor Function from Rat Pancreatic Islets in vitro

Abstract: Parasympathetic system plays an important role in insulin secretion from the pancreas. Cholinergic effect on pancreatic beta cells exerts primarily through muscarinic receptors. In the present study we investigated the specific role of muscarinic M1 and M3 receptors in glucose induced insulin secretion from rat pancreatic islets in vitro. The involvement of muscarinic receptors was studied using the antagonist atropine. The role of muscarinic M1 and M3 receptor subtypes was studied using subtype specific antagonists. Acetylcholine agonist, carbachol, stimulated glucose induced insulin secretion at low concentrations (10−8–10−5 M) with a maximum stimulation at 10−7 M concentration. Carbachol-stimulated insulin secretion was inhibited by atropine confirming the role of muscarinic receptors in cholinergic induced insulin secretion. Both M1 and M3 receptor antagonists blocked insulin secretion induced by carbachol. The results show that M3 receptors are functionally more prominent at 20 mM glucose concentration when compared to M1 receptors. Our studies suggest that muscarinic M1 and M3 receptors function differentially regulate glucose induced insulin secretion, which has clinical significance in glucose homeostasis.

Conducting Polyaniline Composites as Microwave Absorbers

Abstract: Conducting polymers are excellent microwave absorbers and they show technological advantage when compared with inorganic electromagnetic absorbing materials, being light weight , easily processable , and the ability of changing the electromagnetic properties with nature and amount of dopants , synthesis conditions , etc. In this paper we report the synthesis , dielectric properties, and expected application of conducting composites based on polyaniline (PAN). Cyclohexanone soluble conducting PAN composites of microwave conductivity 12.5 S/m was synthesized by the in situ polymerization of aniline in the presence of emulsion grade polyvinyl chloride. The dielectric properties of the composites , especially the dielectric loss, conductivity , dielectric heating coefficient , absorption coefficient , and penetration depth, were studied using a HP8510 vector network analyzer. The microwave absorption of the composites were studied at different frequency bands i.e, S, C, and X bands (2-12 GHz ). The absorption coefficient was found to be higher than 200 m -' and it can be used for making microwave absorbers in space applications . POLYM. COMPOS., 28:588-592, 2007. © 2007 Society of Plastics Engineers