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 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...

In the present study, the effects of caerulein and CCK receptor antagonist< on tolerance to the anti-pentylenetetrazol activity of diazepam has been studied. Different doses of diazepam (20, 30, 35, 40 and 50 mg/kg) were administered intraperitoneally for a period of 6 days in order to induce tolerance to diazepam. 48 h after the last dose of diazepam, a test dose of diazepam was tested for...

Pulsatile secretion of GnRH-1 regulates gonadotropin release from anterior pituitary and thus is essential for reproduction. The present study focused on the role of cholecystokinin (CCK) in the GnRH-1 system. CCK is a neuropeptide abundantly expressed in the brain, which is implicated in activation of female reproductive behaviors and release of anterior pituitary hormones. Using dual-label im...

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...

Subtype-selective antagonists of the peripheral-type (CCK-A) and the central-type (CCK-B) cholecystokinin (CCK) receptors were employed to determine the receptor subtype(s) mediating the modulatory actions of CCK on dopamine-induced changes in exploratory activity at three sites in the mesolimbic pathway of the rat. The CCK-A antagonist L-364,718 (10 ng) blocked CCK potentiation of dopamine-ind...

Cholecystokinin (CCK)-A and CCK-B/gastrin receptors were evaluated with in vitro receptor autoradiography in 406 human tumors of various origins using a sulfated 125I-labeled CCK decapeptide analogue 125I-(D-Tyr-Gly, Nle28,3l)-CCK 26-33 and 125I-labeled Leu15-gastrin as radioligands. CCK-B/gastrin receptors were found frequently in medullary thyroid carcinomas (92%), in small cell lung cancers ...

26 Various molecular forms of cholecystokinin (CCK) reduce food intake in rats. Although CCK-8 is the 27 most studied form, we reported that CCK-58 is the only detectable endocrine peptide form in rats. We 28 investigated the dark phase rat chow intake pattern following injection of CCK-8 and CCK-58. Ad libitum 29 fed male Sprague-Dawley rats were intraperitoneally injected with CCK-8, CCK-58 (...