Photodynamic modulation of cellular functions / 生理学报

Photodynamic action, due to the rather limited lifetime (1 μs) and effective reactive distance of singlet oxygen (< 10 nm), could subcellular-specifically regulate different cellular functions. Photodynamic action could activate permanently cholecystokinin (CCK) 1 receptors, and sensitize or desensitize other G protein-coupled receptors. The emergence in recent years of genetically- encoded protein photosensitisers has enabled more precisely-targeted photodynamic modulation of subcellular organelles and functional proteins. Protein photosensitisers (such as KillerRed, miniSOG or SOPP) expressed on the plasma membrane, mitochondria, lysosomes or endoplasmic reticulum can modulate photodynamically subcellular functions and fine-tune protein activity by targeted photooxidation. With the newly emerged active illumination technique, simultaneous photodynamic action localized at multiple sites is now possible, and the contribution of subcellular regions to the whole cell or individual cells to a cell cluster could be quantitated. Photodynamic action with protein photosensitiser will be a powerful tool for nano-manipulation in cell physiology research.

Effect of Chaiqin Chengqi Decoction on cholecystokinin receptor 1-mediated signal transduction of pancreatic acinar cells in acute necrotizing pancreatitis rats / 中国结合医学杂志

<p><b>OBJECTIVE</b>To investigate the effect of Chaiqin Chengqi Decoction (,CQCQD) on cholecystokinin receptor 1 (CCKR1)-mediated signal transduction of pancreatic acinar cell in rats with acute necrotic pancreatitis (ANP).</p><p><b>METHODS</b>Twenty-seven Sprague-Dawley rats were randomized into three groups: the control group, the ANP group, and the CQCQD group (9 in each group). ANP rats were induced by two intraperitoneal injections of 8% L-arginine (pH=7.0, 4.4 g/kg) over a 2-h period. Rats were treated with 1.5 mL/100 g body weight of CQCQD (CQCQD group) or physiological saline (control and ANP groups) at 2 h interval. And 6 h after induction, pancreatic tissues were collected for histopathological examination. Pancreatic acinar cells were isolated for determination of CCKR1 mRNA and protein expression, phospholipase C (PLC) and inositol-1,4,5-triphosphate (IP3), and determination of fluorescence intensity (FI) as a measure of intracellular calcium ion concentration [Ca(2+)]i.</p><p><b>RESULTS</b>The pancreatic histopathological score (6.2 ± 1.1) and the levels of PLC (1,187.2 ± 228.2 μg/mL) and IP3 (872.2 ± 88.4 μg/mL) of acinar cells in the ANP group were higher than those in the control (2.8 ± 0.4, 682.5 ± 121.8 μg/mL, 518.4 ± 115.8 μg/mL) and the CQCQD (3.8 ± 0.8, 905.3 ± 78.5 μg/mL, 611.0 ± 42.5 μg/mL) groups (P<0.05). [Ca(2+)]i FI for the ANP group (34.8±27.0) was higher than that in the control (5.1 ± 2.2) and CQCQD (12.6 ± 2.5) groups (P<0.05). The expression of pancreatic acinar cell CCKR1 mRNA in the ANP group was up-regulated (expression ratio=1.761; P=0.024) compared with the control group. The expression of pancreatic acinar cell CCKR1 mRNA in the CQCQD group was down-regulated (expression ratio=0.311; P=0.035) compared with the ANP group. The ratio of gray values of the CCKR1 and β-actin in the ANP group (1.43 ± 0.17) was higher than those in the control (0.70 ± 0.15) and CQCQD (0.79 ± 0.11) groups (P<0.05).</p><p><b>CONCLUSIONS</b>Pancreatic acinar cell calcium overload of ANP induced by L-arginine was related to the up-regulated expressions of pancreatic acinar cell CCKR1 mRNA and protein. CQCQD can down-regulate expressions of pancreatic acinar cell CCKR1 mRNA and protein to reduce the PLC and IP3 of pancreatic acinar cells, relieving the calcium overload and reducing the pathological changes in rats with ANP.</p>

Reduction of Food Intake by Fenofibrate is Associated with Cholecystokinin Release in Long-Evans Tokushima Rats

Fenofibrate is a selective peroxisome proliferator-activated receptor alpha (PPARalpha) activator and is prescribed to treat hyperlipidemia. The mechanism through which PPARalpha agonists reduce food intake, body weight, and adiposity remains unclear. One explanation for the reduction of food intake is that fenofibrate promotes fatty acid oxidation and increases the production of ketone bodies upon a standard experimental dose of the drug (100~300 mg/kg/day). We observed that low-dose treatment of fenofibrate (30 mg/kg/day), which does not cause significant changes in ketone body synthesis, reduced food intake in Long-Evans Tokushima (LETO) rats. LETO rats are the physiologically normal controls for Otsuka Long-Evans Tokushima Fatty (OLETF) rats, which are obese and cholecystokinin (CCK)-A receptor deficient. We hypothesized that the reduced food intake by fenofibrate-treated LETO rats may be associated with CCK production. To investigate the anorexic effects of fenofibrate in vivo and to determine whether CCK production may be involved, we examined the amount of food intake and CCK production. Fenofibrate-treated OLETF rats did not significantly change their food intake while LETO rats decreased their food intake. Treatment of fenofibrate increased CCK synthesis in the duodenal epithelial cells of both LETO and OLETF rats. The absence of a change in the food intake of OLETF rats, despite the increase in CCK production, may be explained by the absence of CCK-A receptors. Contrary to the OLETF rats, LETO rats, which have normal CCK receptors, presented a decrease in food intake and an increase in CCK production. These results suggest that reduced food intake by fenofibrate treatment may be associated with CCK production.

Association of CCK1 Receptor Gene Polymorphisms and Irritable Bowel Syndrome in Korean

INTRODUCTION: Cholecystokinin (CCK) belongs to a group of endogenous molecules known as brain-gut neuropeptides and functions as a neuropeptide as well as a gut hormone. It remains unclear whether genetic variation of the CCK receptor plays a role in irritable bowel syndrome (IBS). The aim of this study was to determine and compare the allele and genotype frequencies of the CCK1 receptor polymorphisms between healthy controls and patients with IBS. METHODS: Genotyping of 80 patients with IBS (who met the Rome III criteria) and 76 healthy controls was performed. We performed PCR amplification for the CCK1 receptor intron 1 779 T > C and Exon 1 G > A. We confirmed polymorphisms by direct sequencing method. RESULTS: There was a significantly different trend for genotypic distributions of the CCK1 receptor polymorphism between patients with IBS and healthy controls (p for trend = 0.048). The CCK1 receptor intron 1 779 T >C polymorphic type was more common in patients with 'IBS-constipation predominant (IBS-C) and IBS-mixed (IBS-M) forms' (19/31, 61.3%) than healthy controls 32/76, 42.1% adjusted odd ratio 2.43, 95% Confidence interval 1.01-5.86). The genotypic distributions of the CCK1 receptor exon 1 polymorphism were not significantly different between the two groups (p for trend = 0.223). CONCLUSIONS: CCK1 receptor polymorphisms were associated with IBS. In particular, the CCK1 receptor intron 1 779 T > C polymorphic type was associated with 'IBS-C and IBS-M'. Further studies are needed in larger number of patients with an even distribution of IBS subtypes.

Effects of Poly I:C in inducing growth inhibition and apoptosis of human hepatocellular carcinoma cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the effect and mechanism of Poly I:C in inducing growth inhibition and apoptosis of human hepatocellular carcinoma SMMC-7721 cells.</p><p><b>METHODS</b>SMMC-7721 cells were treated with different doses of Poly I:C for 24, 48, and 72 h, and the cell growth inhibition rate was analyzed with CCK-8 assay. The cell cycle and the apoptosis were analyzed using flow cytometry with Annexin-V and PI staining, and quantitative RT-PCR analysis were used to detect the expression of TLR3, TRIF, and IFN-beta mRNA in cells.</p><p><b>RESULTS</b>In the cells exposed to Poly I:C at low, moderate, and high doses, the inhibitory rates was the highest in high-dose Poly I:C group, and at a given Poly I:C dose, prolonged exposure resulted in significantly increased cell growth inhibition rate (P<0.05). Flow cytometry showed that Poly I:C induced cell apoptosis in a time- and dose-dependent manner and significantly increased the percentage of G1-phase cells as compared with that in the control group. The mRNA level of TLR3, TRIF, and IFN-beta were also increased following Poly I:C treatment in comparison with the control group.</p><p><b>CONCLUSION</b>Poly I:C can induce significant growth inhibition and apoptosis of SMMC-7721 cells in a dose- and time-dependent manner possibly by causing cell cycle arrest and TLR3 signaling pathway activation that leads to IFN-beta production and cell apoptosis.</p>

The effect of formalin-induced pain on CCK in rat spinal cord neurons / 中国应用生理学杂志

<p><b>AIM</b>CCK is one of the strongest endogenous anti-opioid substances and suppresses morphine tolerance which results from long term use of morphine. This study explores the modulatory effect of CCK on pain formalin-induced.</p><p><b>METHODS</b>The effect of formalin-induced pain on CCK immunoreactivity in rat sensory neurons was observed through immunohistochemistry technique.</p><p><b>RESULTS</b>After 1 h of subcutaneous injection of formalin in one paw of rats, the number of positive neurons of CCK immunoreactivity in spinal cord neurons was obviously increased and greater than that of non-injection side (P <0.01). The semi-quantitative optical density average values of CCK immunoreactivity neurons were 0.397 +/- 0.014 and 0.295 +/- 0.007 in injection side and non-injection side respectively, the difference was obvious (P < 0.01). After 3 h of subcutaneous injection of formalin in one paw of rats, the semi-quantitative optical density average values of CCK immunoreactivity neurons were 0.366 +/- 0.009 and 0.303 +/- 0.005 in injection side and noninjection side respectively, the difference was significant (P < 0.01).</p><p><b>CONCLUSION</b>Formalin-induced pain can significantly change semi-quantitative optical density average value of CCK immunoractivity in spinal cord neurons, this indicates CCK participates in modulation of pain.</p>

Activation of neural cholecystokinin-1 receptors induces relaxation of the isolated rat duodenum which is reduced by nitric oxide synthase inhibitors

Cholecystokinin (CCK) influences gastrointestinal motility, by acting on central and peripheral receptors. The aim of the present study was to determine whether CCK has any effect on isolated duodenum longitudinal muscle activity and to characterize the mechanisms involved. Isolated segments of the rat proximal duodenum were mounted for the recording of isometric contractions of longitudinal muscle in the presence of atropine and guanethidine. CCK-8S (EC50: 39; 95 percent CI: 4.1-152 nM) and cerulein (EC50: 58; 95 percent CI: 18-281 nM) induced a concentration-dependent and tetrodotoxin-sensitive relaxation. Nomeganitro-L-arginine (L-NOARG) reduced CCK-8S- and cerulein-induced relaxation (IC50: 5.2; 95 percent CI: 2.5-18 æM) in a concentration-dependent manner. The magnitude of 300 nM CCK-8S-induced relaxation was reduced by 100 æM L-NOARG from 73 ± 5.1 to 19 ± 3.5 percent in an L-arginine but not D-arginine preventable manner. The CCK-1 receptor antagonists proglumide, lorglumide and devazepide, but not the CCK-2 receptor antagonist L-365,260, antagonized CCK-8S-induced relaxation in a concentration-dependent manner. These findings suggest that CCK-8S and cerulein activate intrinsic nitrergic nerves acting on CCK-1 receptors in order to cause relaxation of the rat duodenum longitudinal muscle.

Regulative effects of ovarian steroids on rat gastric motility and sensitivity / 生理学报

Women often complain gut symptoms during pregnancy and the luteal phase of the menstrual cycle. To investigate the relationship between ovarian steroids and the abnormal gut motility and sensitivity, the expressions of cholecystokinin (CCK), calcitonin gene-related peptide (CGRP) and their receptors in stomach were studied in ovariectomized rats. Blood samples were collected for estradiol (E(2)), progesterone (P(4)), CCK and CGRP radioimmunoassay. Expression of CCK(A) receptor in fundus was assessed by Western blot and CGRP receptor was determined by (125)I-CGRP radioligand binding assay (RBA). The replacement therapy with estradiol benzoate (EB) could dose-dependently increase the plasma CCK level and the expression of gastric CCK(A) receptor (P<0.05 respectively). P(4) replacement therapy could stimulate the release of CGRP and increase the binding sites of CGRP receptors in stomach (P<0.05 respectively). The combined effect of EB and P(4) was to stimulate the release of CCK and CGRP, and to increase the expressions of gastric CCK(A) and CGRP receptors. These results indicate that EB could inhibit gastric emptying by increasing CCK secretion and CCK(A) receptor expression in ovariectomized rats. P(4) could increase gut sensitivity by up-regulating the release of CGRP and the activity of CGRP receptor. It could be deduced from these observations that CCK(A) and CGRP receptor antagonists could be used for female patients who suffer from gastrointestinal dysfunction closely related with the menstrual cycle, such as distension, satiety, bloating and abdominal pain.

Functional dyspepsia: relationship between clinical subgroups and Helicobacter pylori status in Western Turkey

The etiology of functional dyspepsia is not known. The objective of the present study was to determine the characteristics of functional dyspepsia in Western Turkey. We divided 900 patients with functional dyspepsia into three subgroups according to symptoms: ulcer-like (UL), 321 (35.6 percent), motility disorder-like (ML), 281 (31.2 percent), and the combination (C) of these symptoms, 298 (33.1 percent). All patients were submitted to endoscopic evaluation, with two biopsies taken from the cardia and corpus, and four from the antrum of the stomach. All biopsy samples were studied for Helicobacter pylori (Hp) density, chronic inflammation, activity, intestinal metaplasia, atrophy, and the presence of lymphoid aggregates by histological examination. One antral biopsy was used for the rapid urease test. Tissue cagA status was determined by PCR from an antral biopsy specimen by a random sampling method. We also determined the serum levels of tumor necrosis factor-alpha (TNF-alpha) and gastrin by the same method. Data were analyzed statistically by the Kolmogorov-Smirnov test and by analysis of variance. Hp and cagA positivity was significantly higher in the UL subgroup than in the others. The patients in the ML subgroup had the lowest Hp and cagA positivity and Hp density. The ML subgroup also showed the lowest level of Hp-induced inflammation among all subgroups. The serum levels of TNF-alpha and gastrin did not reveal any difference between groups. Our findings show a poor association of Hp with the ML subgroup of functional dyspepsia, but a stronger association with the UL and C subgroups

Regulatory effect of clearing-heat secreting-bile regulating-qi flow and activating blood circulation principle on cholecystokinin receptor / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To explore the regulatory effect of clearing-Heat secreting-bile regulating-Qi flow and activating blood circulation (CSRA) principle on cholecystokinin receptor (CCK-R) and its mechanism.</p><p><b>METHODS</b>Cholecystokinin (CCK) in serum of portal venous blood, maximum binding capacity (Bmax) and affinity (Kd) of CCK-R levels in gallbladder of guinea pigs allocated in four groups (control, high cholesterol, natural recovery and treated groups) were determined using radioimmunoassay and radioligand receptor assay (RRA). At the same time, changes of fasting volume (FV) and postprandial volume (PV) of gallbladder, fasting and postprandial bile (FB and PB) in gallbladder, gallbladder contraction rate (GCR) and cholesterol concentration (CC) in bile were observed.</p><p><b>RESULTS</b>Compared with the control group, after two weeks of high cholesterol feeding, increase of FV, FB, PV, PB and CC (P < 0.05), and decrease of GCR (P < 0.01) and Bmax were found in cholesterol group, but with no significant change in Kd and CCK level. The above-mentioned criteria were restored to normal range in the treated group.</p><p><b>CONCLUSION</b>CSRA principle could promote the recovery of gallbladder contraction by regulating CCK-R expression in it, its mechanism is possibly correlated with reduction of cholesterol concentration in bile.</p>

Effect of cholesterol in bile on cholecystokinin receptor in the gallbladder / 中华外科杂志

<p><b>OBJECTIVE</b>To assess the effect of cholesterol in bile on cholecystokinin receptor (CCK-R) in the gallbladder.</p><p><b>METHODS</b>One hundred Guinea pigs were randomly divided into four groups, 25 animals for each. The control group was fed a standard diet, and the cholesterol group fed a diet containing 2% cholesterol. After taking the 2% cholesterol diet for two weeks, the natural group persisted on the standard diet, and the treated group was perfused by traditional Chinese medicine. Serum cholecystokinin (CCK) level in the portal vein and maximal binding capacity (B(max)) and Kd of CCK-R in the gallbladder were measured in the four groups by RIA and RBA, and the concentrations of cholesterol in bile were also observed.</p><p><b>RESULTS</b>Compared with the control group, after high-cholesterol feeding for two weeks, the gallbladder emptying rate [(65.83 +/- 7.32)% approximately (47.22 +/- 5.24)%] and B(max) of CCK-R [(60 +/- 27) approximately (32 +/- 13) fmol/mg protein] and in decreased fasting gallbladder volume (FV) [(0.89 +/- 0.26) approximately (1.34 +/- 0.61) cm(3)] and concentration of cholesterol [(0.44 +/- 0.11) approximately (0.60 +/- 0.13) mmol/L] in bile increased, but no change was in the serum CCK level and Kd of CCK-R in the cholesterol group. Compared with the natural group, after two-week in take of herb decoction of qingre lidan and liqi huoxue, FV [(1.27 +/- 0.60) approximately (0.90 +/- 0.27) cm(3)], RV [(0.85 +/- 0.45) approximately (0.32 +/- 0.12) cm(3)], FB [(0.92 +/- 0.35) approximately (0.73 +/- 0.21) cm(3)], RB [(0.76 +/- 0.34) approximately (0.29 +/- 0.08) cm(3)] in the treated group decreased significantly; but gallbladder emptying rate [(43.06 +/- 4.27)% approximately (67.01 +/- 6.82)%] increased significantly. The concentration of cholesterol in bile was lower in the treated group than in the natural group [(0.59 +/- 0.14) approximately (0.43 +/- 0.10) mmol/L], but no change was found in the serum CCK level. Bmax of CCK-R in the treated group increased significantly [(39 +/- 19) approximately (59 +/- 11) fmol/mg protein], Kd of CCK-R showed no significant changes between the treated group and natural group.</p><p><b>CONCLUSION</b>High cholesterol in gallbladder bile causes defective muscle contraction by down-regulating CCK-R in the gallbladder, so the reduction of cholesterol concentration of bile may contribute to gallbladder contraction.</p>

Effects of cholecystokinin octapeptide on rat cardiac function and the receptor mechanism / 生理学报

The aim of this study was to explore the effects of cholecystokinin octapeptide (CCK-8) on cardiac function and the receptor mechanism in anesthetized rats. The mean arterial pressure (MAP), heart rate (HR), the left ventricle systolic pressure (LVP) and the maximal/minimum rate of LVP (+/-LV dp/dt(max)) were measured. The results obtained are as follows. (1) Low dose of CCK-8 (0. 4 microgram/kg i.v.) caused tachycardia and slight increase in MAP, LVP and LV dp/dt(max) (P<0.01), while medium dose (4.0 microgram/kg i.v.) and high dose of CCK-8 (40 microgram/kg i.v.) elicited a bradycardia and marked increase in MAP, LVP and LV dp/dtmax (P<0.01). (2) Proglumide (1.0 mg/kg i.v.), a CCK-receptor (CCK-R) antagonist, significantly inhibited the pressor effects of CCK-8, whilst it reversed the bradycardic responses (P<0.01). (3) Using reverse transcription polymerase chain reaction (RT-PCR), CCK-A receptor (CCK-AR) and CCK-B receptor (CCK-BR) mRNA were expressed in myocardium of rats. The above results indicate that CCK-8 may enhance cardiac function in a dose-dependent manner and elicit a change in HR, which is likely induced by the activation of CCK-R on myocardium.

Effects of cholecystokinin octapeptide on neuronal activities in the rat nucleus tractus solitarius

Cholecystokinin (CCK) is a gastrointestinal hormone which plays an important role in satiety and gastric motility. It is also widely distributed throughout the central nervous system, where it appears to be involved in the central control of anxiety, feeding behavior and nociception. Two distinct CCK receptor types, CCKA and CCKB, have been found in the brain. Both CCK receptors coexist in the rat nucleus tractus solitarius (NTS), which is the primary center for the coordination of peripheral and central activities related to gastrointestinal, cardiovascular and respiratory functions. In order to study ionic actions of CCK on each type of receptor, we investigated the effects of CCK-8S on neurons located in the NTS of the rat using whole-cell patch-clamp recordings in brainstem slices. Application of CCK-8S, under current clamp, produced a membrane depolarization accompanied by action potential firing. This CCK-evoked excitation was dose-dependent (10 nM ~ 10 micrometer) and observed in more than 60% of NTS neurons. Under voltage clamp conditions, CCK-8S induced an inward current with a notably increased spontaneous excitatory synaptic activity. However, CCK-8S did not significantly change the amplitude of pharmacologically isolated and evoked EPSP(C)s. Using selective CCKA and CCKB receptor antagonists, we observed two different effects of CCK-8S, which suggest CCKA receptor-mediated inhibitory and CCKB receptor-mediated excitatory effects in the NTS. These results may help to explain the ability of CCK to modulate gastrointestinal and other reflex systems in the NTS.

Rol del tejido adiposo / Adipose tissue role

Currently the research on adipose tissue has yielded same insights of itïs function. On the embrionary state the differentiation between white adipose tissue and brown adipose tissue and brown adipose tissue signals different functions. The presence of multiple receptors and actions define itïs autocrine, paracline and endocrine roles

Molecular shape analysis for quantitative drug design

One of the goals of the rational drug design using quantitative structure-activity relationship [QSAR]' is to derive a relationship between some numerical expression of the structures of compounds and their activity. The objective is to predict the structure[s] of more active compounds. The pioneering work of Hansch el at. provided a formula for deriving QSARs, which could be used to predict activity from structure. A major limitation of this approach is that its descriptors are derived from 2-dimensional structures. Comparative molecular field analysis, CoMFA, molecular shape analysis, MSA, distance geometry, and molecular matrices are four methods which explicitly treat the 3-dimensional structure of the ligand and thus yield 3-dimensional quantitative structure-activity relationships, 3D-QSARs. The present article will review the molecular shape analysis MSA, as one of the most valuable 3D-QSAR method. MSA seeks the active conformation of a molecule, expresses molecular shape similarity in terms of a variety of scalar descriptors, such as common overlap steric volume Vo [COSV], measured relative to some reference compound and conformation, and permits the use of other common 2- and 3-dimensional descriptors in the development of structure-activity models

Synthesis and biological activities of some human gastrin analogs

The synthesis of analogs of the C-terminal tridecapeptide of gastrin in described. These pseudopeptide analogs were obtained either by replacing the C-terminal phenylalanine amide with 2-phenylethytalcohol or with 2-phenylethylamine, or by replacing the peptid bond between Trp and Leu, or between Leu and Asp with an aminomethylene (CH2NH). The ability of these compounds to stimulate gastric acid secretion in anesthetized rats and to inhibit binding of labeled CCK-8 to isolated cells from rabbit fundic mucosa was tested. [desPhe13, Leu11]-HG-12-I-beta-phenylethylester 33, [desPhe13, Leu11]-HG-12-II-beta-phenylethylester 38 [desPhe13, Leu11]-HG-12-I-beta-phenylethylamide 32, and [desPhe13, Leu11]-HG-12-II-beta-phenylethylamide 37 acted as gastrin receptor antagonists, while [Trp10-((CH2NH)-Leu11]-HG-13-I 31 and (Trp10-((CH2NH)-Leu11]-HG-13-II 36 acted as agonists. Unexpectedly, [Leu11-((CH2NH)-Asp12]-HG-13-I 30 and [Leu11-((CH2NH)-Asp12]-HG-13-II 35 were almost devoid of affinity for the gastrin receptor.

Secretory response of cultured acinar cells of rat pancreas to cholecystokinin

To determine the adequate models for studying the functions of pancreatic acinar cells, secretory responses to CCK and to CCK receptor antagonist, L-364, 718 were examined in freshly isolated cells and confluent monolayer cells. The results showed that as CCK concentration increased, releases of amylase and lipase increased dose-dependently reaching a maximum at 10(-9) M in acinar cells cultured in serum-containing media as well as in serum-free media. Acinar response to CCK was partially inhibited by L-364, 718, L-364, 718 itself had no effect on the releases of both amylase and lipase. Confluent monolayer of acinar cells released relatively low levels of enzymes and exhibited less response to CCK. In conclusion, short-term culture of acinar cells would be suitable to study the regulation of pancreatic enzyme secretion, and serum factors do not influence acina response to the secretagogues. However, confluency of the acinar cells resulted in the loss of their secretory potential in the aspect of amylase and lipase release.

A quantitative structure-activity relationship study of ligands exhibiting agonist and antagonist actions with cholecystokinin-receptors.

Observed biological activities of substituted phenyl urea/thiourea tetrapeptides as agonists with the cholecystokinin-alimentary canal (CCK-A) receptor, and (R)-4-benzamido-5-oxopentanoic acid derivatives with both peripheral (CCK-A) and the central (CCK-B) (brain) receptors have been shown to be correlated with various physicochemical, e.g. pi, sigma, and structural, e.g. Vw and dummy, I, parameters. These results were, then interpreted to predict promising criteria for having ligands with better affinity with the CCK receptors.

Antral gastrin cells in helicobacter pylori gastritis: quantitative immunohistochemical study

The number of antral gastrin cells [G cells] and their staining pattern was evaluated in 28 gastroscopic biopsies without evidence of Helicobacter-like organisms [HLOs], as a control group, and 42 gastroscopic biopsies with HLOs, as a test group. There was no significant difference in the number of G cells per gland in relation to the presence or absence of HLOs, degree of inflammation, type of gastritis and activity of inflammation [P >0.05]. The intensity of immunostaining was deeper in association with HLOs positive cases [++] than the negative group [+]. The intensity of G cell staining was not affected by the severity of HLOs. The intensity of staining was more in active than quiescent gastritis, specially when associated with HLOs. The degree of gastritis has direct effect on the intensity of staining of G cells, specially when associated with HLOs