We have developed a model of GABAergic synaptic transmission mediated by GABA A and GABA B receptors, including cooperativity in the G-protein cascade mediating the activation of K + channels by GABA B receptors. If the binding of several G-proteins is needed to activate the K + channels, then only a prolonged activation of GABA B receptors evoked detectable currents. This could occur if strong...

A reduction in the release of substrate amino acids from skeletal muscle largely explains the decrease in gluconeogenesis characterizing prolonged starvation. Brief starvation is associated with an increase in gluconeogenesis, suggesting increased release of amino acids from muscle. In the present studies, accelerated amino acid release from skeletal muscle induced by brief starvation was sough...

A vasoactive intestinal peptide (VIP)-like peptide is released by axonal stimulation in the giant axon-Schwann cell preparation from the tropical squid Sepioteuthis sepioidea. It is also released by direct application of l-glutamate, the giant axon-Schwann cell signalling molecule in this preparation. The release of the peptide parallels the release of acetylcholine from the Schwann cells thems...

Prolonged exposure to noradrenaline (NA) brings about an increase in the release of prostaglandin (PG)-like material from rat aortic strip. The release is greater with oxymetazoline while methoxamine decreases it. These effects are blocked by yohimbine and prazosin respectively. Pretreatment with 6-OHDA or reserpine diminishes the release of PG-like material. Barium chloride, a non-specific spa...

Floating microspheres have been utilized to obtain prolonged and uniform release of drug in the stomach for development of once-daily formulations. A controlled-release system designed to increase residence time in the stomach without contact with the mucosa was achieved through the preparation of floating microspheres by the emulsion solvent diffusion technique, using (?) calcium silicate (CS)...

Oral controlled drug delivery systems represent the most popular form of sustained drug delivery systems for the obvious advantages of oral route of drug administration. Such systems release the drug with constant or variable release rates. The oral controlled release systems shows a typical pattern of drug release in which the drug concentration is maintained in the therapeutic window for a pr...

Floating microspheres have been utilized to obtain prolonged and uniform release of drug in the stomach for development of once-daily formulations. A controlled-release system designed to increase residence time in the stomach without contact with the mucosa was achieved through the preparation of floating microspheres by the emulsion solvent diffusion technique, using (i) calcium silicate (CS)...

In order to reduce dosing frequency, a sustained release dosage form of betahistine dihydrochloride was developed as a twice daily controlled release tablet formulation that could be used to decrease vertigo resulted in Meniere's disease for a prolonged time. Six formulations were developed by using Methocel K4M CR, Methocel K15M CR and Methocel K 100 LVCR as single and combinations in differen...

Background—The mechanisms underlying the suppression of somatostatin dependent reflexes in Helicobacter pylori infection are not fully determined. The H pylori product N-methylhistamine and inflammatory mediators such as tumour necrosis factor-á (TNF-á) may be responsible for the alterations in somatostatin release. Aims—To examine the eVect of N-methylhistamine on somatostatin release from cul...

Abstract The present study focuses on the evaluation of a novel prolonged action fertilizer that has been encapsulated by combination carboxymethyl cellulose (CMC) and humic acid (HA). aim this research was to investigate release essential plant nutrients: phosphorus, nitrogen, potassium. This investigated material composition nutrient properties CMC HA. these nutrients determined quantifying t...