In this work, we 1) synthesized rat CCK-58, 2) determined the amounts and forms of rat CCK in whole blood after stimulation of its release by casein, 3) determined the potency of CCK-8 and CCK-58 peptides to displace labeled CCK-8 from CCK(A) and CCK(B) receptors transfected into Chinese hamster ovary (CHO) cells, and 4) examined the biological actions of CCK-8 and rat CCK-58 in an anesthetized...

the activity of one of the metabolizing enzymes of - aminobutyric acid, (gaba), was determined in mouse hypothalamus after peripheral injections of cholecystokinin-8 (cck-8) and caerulein (cln). the activity of this rate-limiting enzyme, l-glutamic acid decarboxylase, (gad), did not change thirty minutes after peripheral injections of either cck-8 or cln in doses of 50g/kg body weight. howeve...

Nonsulfated CCK(58) [CCK(58)(ns)] has not been considered to be of biological importance because CCK(58)(ns) binds poorly to the CCK(A) receptor and has only been identified once in intestinal extracts. In this work, a radioimmunoassay specific for the COOH-terminal region of gastrin and CCK (antibody 5135) was used to monitor the purification of CCK molecular forms from canine intestinal extra...

Various molecular forms of CCK reduce food intake in rats. Although CCK-8 is the most studied form, we reported that CCK-58 is the only detectable endocrine peptide form in rats. We investigated the dark-phase rat chow intake pattern following injection of CCK-8 and CCK-58. Ad libitum-fed male Sprague-Dawley rats were intraperitoneally injected with CCK-8, CCK-58 (0.6, 1.8, and 5.2 nmol/kg), or...

Cholecystokinin (CCK) is an abundant neuropeptide involved in normal behaviour and pathophysiological conditions. Recently, CCK was shown to act as a molecular switch for perisomatic inhibition in the hippocampus, by directly depolarizing parvalbumin expressing (PV+) basket cells while indirectly depressing GABA release from CCK expressing (CCK+) basket cells. However, whether these two CCK-med...

BACKGROUND Although the existence of cholecystokinin-like immunoreactivity (CCK-LI) in rat pancreas had been reported previously, it was never clearly demonstrated whether CCK is produced in rat pancreatic islets. AIMS The purpose of this study was to elucidate the source of the CCK-LI, the molecular properties of CCK, and the expression of the CCK gene in islet cells. METHODS Immunohistoch...

The activities of 4-aminobutyric-2-oxoglutaric acid transaminase (GABA-T) and succinate semialdehyde dehydrogenase (SSADH) were determined in mouse hypothalamus after peripheral injections of cholecystokinin-8 (CCK-X)and/or caerulein (CLN). GABA transaminase activity was measured utilizing endogenous succinate semialdellyde dehydrogenase to convert the product of GAB A-T, succinate semiald...

The functional significance of the extracellular amino-terminal region and of three highly conserved aromatic residues present in the fifth (TM-V) and sixth (TM-VI) transmembrane domains of the rat cholecystokinin (CCK)B receptor, transfected in Cos-7 cells, was investigated by site-directed mutagenesis. The amino-terminal region of the CCKB receptor seemed to be weakly involved in CCK binding ...

the activities of 4-aminobutyric-2-oxoglutaric acid transaminase (gaba-t) and succinate semialdehyde dehydrogenase (ssadh) were determined in mouse hypothalamus after peripheral injections of cholecystokinin-8 (cck-x)and/or caerulein (cln). gaba transaminase activity was measured utilizing endogenous succinate semialdellyde dehydrogenase to convert the product of gab a-t, succinate semialdehyde...

Cholecystokinin (CCK) is one of the most abundant neuropeptides in the brain, where it interacts with two G protein-coupled receptors (CCK-1 and CCK-2). Activation of both CCK receptors increases the activity of PLC, resulting in increases in intracellular calcium ion (Ca(2+)) release and activation of PKC. Whereas high density of CCK receptors has been detected in the superficial layers of the...