Free fatty acids regulate insulin secretion from pancreatic beta cells through GPR40

Diabetes, a disease in which carbohydrate and lipid metabolism are regulated improperly by insulin, is a serious worldwide health issue. Insulin is secreted from pancreatic beta cells in response to elevated plasma glucose, with various factors modifying its secretion. Free fatty acids (FFAs) provide an important energy source as nutrients, and they also act as signalling molecules in various cellular processes, including insulin secretion. Although FFAs are thought to promote insulin secretion in an acute phase, this mechanism is not clearly understood. Here we show that a G-protein-coupled receptor, GPR40, which is abundantly expressed in the pancreas, functions as a receptor for long-chain FFAs. Furthermore, we show that long-chain FFAs amplify glucose-stimulated insulin secretion from pancreatic beta cells by activating GPR40. Our results indicate that GPR40 agonists and/or antagonists show potential for the development of new anti-diabetic drugs.     

Dopamine-induced relaxation in human pulmonary arteries

Dose-dependent relaxations were induced by dopamine in human pulmonary arteries that had been contracted with prostaglandin F2 alpha without alpha-adrenergic blocking agents. The dopamine-induced relaxation was inhibited by haloperidol and fluphenazine, but not by domperidone, suggesting that this relaxation was mediated via DA1 receptors.     

An open environment for cooperative equational solving

We describe a system called CFLP which aims at the integration of the best features of functional logic programming (FLP), cooperative constraint solving (CCS), and distributed computing. FLP provides support for defining one’s own abstractions over a constraint domain in an easy and comfortable way, whereas CCS is employed to solve systems of mixed constraints by iterating specialized constraint solving methods in accordance with a well defined strategy. The system is a distributed implementation of a cooperative constraint functional logic programming scheme that combines higher-order lazy narrowing with cooperative constraint solving. The model takes advantage of the existence of several constraint solving resources located in a distributed environment (e. g., a network of computers), which communicate asynchronously via message passing. To increase the openness of the system, we are redesigning CFLP based on CORBA. We discuss some design and implementation issues of the system.     

Serum thymic factor as a radioprotective agent promoting survival after X-irradiation

Summary Serum thymic factor (FTS, zinc-free thymulin) protected mice from death after whole-body X-irradiation. It was significantly radioprotective even when administered after irradiation, but it was more effective when administered both before and after irradiation. The protective effect appears to be due to the enhancement of hematologic recovery in the animals.     

Lipid peroxidation in rabbit reticulocytes

Summary Lipid peroxides in rabbit erythrocytes and plasma were determined while anemia was induced by daily bleeding. They increased as reticulocytes increased and returned to normal with the morphological transformation to mature cells.This work was supported in part by a grant-in-aid from the Japan Medical Research Foundation and a grant-in-aid (project No. 56570363) from the Ministry of Education, Science and Culture of Japan.     

Calcitonin gene related peptide stimulates adenylate cyclase activity in rat striated muscle

Summary Rat calcitonin gene related peptide (CGRP) and salmon calcitonin (CT) stimulated adenylate cyclase activity in a dose-dependent manner in the rat diaphragm and in the kidney. The ED₅₀ value of rat CGRP was lower and that of salmon CT was higher in the diaphragm than in the kidney. These results suggest that CGRP stimulates adenylate cyclase activity in the striated muscle by reacting with sites distinct from the site in the kidney.     

Alpha-adrenoceptor blocking action of hymenin, a novel marine alkaloid

In the rabbit isolated aorta, hymenin (10(-6) M), a novel marine alkaloid, caused a parallel rightward shift of the dose-response curve for norepinephrine without affecting that for histamine or KCl, suggesting that hymenin is a competitive antagonist of alpha-adrenoceptors in vascular smooth muscles.     

Appearance of sperm activation factors in the ovary of the sea urchinHemicentrotus pulcherrimus with maturation

Summary Ovaries of the sea urchinHemicentrotus pulcherrimus were extracted with 70% ethanol. The extracts were polarographically assayed for respiration-stimulating activity toward homologous spermatozoa. The data of the bioassay and light microscopic observation on thin sections of the ovaries showed detectable activity only in mature ovaries.We thank the Misaki Marine Biological Station for kindly supplying us with specimens. This work was supported in part by a grant from the Ministry of Education, Science and Culture of Japan.