|
1. |
Ethacrynic Acid and Sulphasalazine Inhibit the Generation of Leukotriene C4in Rat Stomachs: A Possible Gastric Anti-Ulcer Mechanism in Cold-Restraint-Stressed Rats |
|
Pharmacology,
Volume 44,
Issue 4,
1992,
Page 177-189
G.P Garg,
C.H. Cho,
C.W. Ogle,
Preview
|
PDF (2141KB)
|
|
摘要:
The role of gastric glandular mucosal leukotriene C4 in gastric ulceration, produced by restraint at 4 °C (stress) for 2 h in rats, was studied in relation to the ulcer-preventing effects of ethacrynic acid, sulphasalazine and its constituents (sulphapyridine and 5-aminosalicylic acid), AA-861 and ONO-1078. Stress itself significantly raised mucosal leukotriene C4 levels; pretreatment with ethacrynic acid, sulphasalazine, sulphapyridine or AA-861 antagonised these changes and reduced the severity of gastric ulceration. Mucosal mast cell degranulation was prevented by ethacrynic acid, sulphasalazine, 5-aminosalicylic acid, AA-861 or ONO-1078; the mucus-depleting effect of stress was also reversed by all these drugs, except for 5-aminosalicylic acid. The anti-ulcer effect of ethacrynic acid and sulphasalazine appears to be related to their influence on glandular mucosal leukotriene C4 levels
ISSN:0031-7012
DOI:10.1159/000138917
出版商:S. Karger AG
年代:1992
数据来源: Karger
|
2. |
Histamine H3Receptors Are Not Involved in the Regulation of Rat Gastric Secretion |
|
Pharmacology,
Volume 44,
Issue 4,
1992,
Page 190-195
Gabriella Coruzzi,
Maristella Adami,
Giulio Bertaccini,
Preview
|
PDF (926KB)
|
|
摘要:
The effects of histamine H3 receptor activation [(R)α-methyl-histamine] and blockade (thioperamide) on rat gastric secretion were determined in vivo and in vitro. (R)α-Methylhistamine (0.1-5 µmol/kg i.p.) did not modify secretory volume and acidity in pylorus-ligated rats; it did not affect basal acid secretion and the secretion stimulated by histamine, pentagastrin and 2-deoxy-.D-glucose in the lumen-perfused stomach of anaesthetized rats, when administered by continuous infusion (0.01-1 µmol/kg/h) or bolus injection (0.05-25 µmol/kg). In this preparation, the H3 agonist increased acid secretion at doses of 3-25 µmol/kg i.v., the effect being antagonized by famotidine. In the isolated gastric fundus from immature rats both (R)α-methylhistamine (0.01-10 µmol/l) and thioperamide (0.01-1 µmol/l) were totally ineffective against both spontaneous and stimulated gastric secretion. These results suggest that histamine H3 receptors are unlikely to have a role in regulating gastric acid secretion in
ISSN:0031-7012
DOI:10.1159/000138918
出版商:S. Karger AG
年代:1992
数据来源: Karger
|
3. |
Central and Peripheral Motor Effects of Galanin on the Duodenojejunum and Colon in Fed Rats |
|
Pharmacology,
Volume 44,
Issue 4,
1992,
Page 196-205
J.P. Ferré,
Y. Ruckebusch,
G. Soldani,
Preview
|
PDF (1526KB)
|
|
摘要:
The effects of intraperitoneal, intrathecal and intracerebroventricular injections of the peptide galanin (GAL) on duodenojejunal and colonic motility were studied in conscious fed rats. At 0.3-3.0 nmol/rat, intraperitoneal GAL restored the ‘fasted pattern’ of duodenojejunal activity, i.e. the migrating myo-electric complex (MMC) was restored for a short period of time, and the MMC frequency was not significantly different from that observed before feeding. In addition, the activity of the proximal but not of the distal colon was significantly increased by GAL administration. The intracerebroventricular administration of GAL (0.03-0.3 nmol/rat) induced an MMC fasted pattern on the duodenojejunum after a latency period of about 1 h. In these experiments proximal colonic motor activity was significantly increased for 120-180 min. GAL given intrathecally (0.03-0.3 nmol/rat) induced a long-lasting fasted pattern of the intestinal activity within 10-20 min which was not dose dependent in duration, while the motility index of the proximal colon was significantly increased. Pretreatment with naloxone prevented the specific effects of GAL, given intracerebroventricularly or intrathecally, on the duodenojejunum and colon and the colonic response, but not the restoration of the MMC pattern on the duodenojejunum, induced by GAL given intraperitoneally. Ketoprofen pretreatment was completeley ineffective. These observations indicate a plurality of sites of action of GAL on digestive tract motility including local duodenal receptors and suggest the importance of a spinal component in the control of motility by GAL when given intrathecally. Moreover the present results indicate the involvement of opioid receptors in the fasted pattern induced by GAL given intracerebroventricularly or intrathecally and in the colonic effects regardless of the route of administrat
ISSN:0031-7012
DOI:10.1159/000138919
出版商:S. Karger AG
年代:1992
数据来源: Karger
|
4. |
Characteristics of Vasoinhibitory Action of FK 453 (a Pyrazolo-Pyridine Derivative), a New Antihypertensive Agent with Diuretic Action in Isolated Rabbit Aorta |
|
Pharmacology,
Volume 44,
Issue 4,
1992,
Page 206-214
Nobuhiro Satake,
Qin Zhou,
Natsuki Sato,
Masahiko Matsuo,
Tadashi Sawada,
Shoji Shibata,
Preview
|
PDF (1382KB)
|
|
摘要:
The vasoinhibitory effect of FK 453 was examined in isolated rabbit aorta. FK 453 inhibited contractile responses to norepinephrine, angiotensin-I and KCl. Pretreatment of the tissue with FK 453 failed to affect the relaxing effect of verapamil on the KCl response and the inhibitory effect of prazosin on the phenylephrine response. FK 453 inhibited both the residual norepinephrine response and the subsequent Ca2+ response in a Ca2+-free medium containing EGTA and nifedipine. The inhibitory effect of a combined treatment with either FK 453 plus nitroglycerin or FK 453 plus theophylline, but not with FK 453 plus M & B 22,948 (2-o-propoxyphenyl-8-azapurine-6-one; May & Baker), was much greater than that of any single treatment. Pretreatment with FK 453 also potentiated relaxing effects of nitroglycerin and isoproterenol on the PGF2α response. The effect of a combined treatment with FK 453 plus theophylline, but not with FK 453 plus M & B 22,948, was much greater than that of any single treatment. FK 453 also inhibited the activity of phosphodiesterase from canine aorta to convert cyclic [3H]-GMP and cyclic [3H]-AMP to 5’-GMP and 5’-AMP, respectively. These results suggest that the inhibitory action of FK 453 is not due to inhibition of voltage-operated Ca2+ channels or α-adrenoceptors, but due to increase in cyclic GMP
ISSN:0031-7012
DOI:10.1159/000138920
出版商:S. Karger AG
年代:1992
数据来源: Karger
|
5. |
Microcomputer-Aided System for Electrocardiograms and Blood Pressure Analysis during Drug-Induced Transient Periods |
|
Pharmacology,
Volume 44,
Issue 4,
1992,
Page 215-224
M.S. Young,
K.W. Lin,
M.T. Lin,
Preview
|
PDF (1481KB)
|
|
摘要:
In the current experiments, we have developed a microcomputer-aided system for amplitude and duration parameter analysis of electrocardiogram (ECG) and blood pressure (BP) waveforms during the drug-induced transient period. Both ECG and BP are monitored, amplified and recorded using standard techniques. For studying the parameter variation trend, the time course of each parameter was produced. Based on these requirements, the present system combined data acquisition, data selection, data analysis, graph plotting and some experimental techniques to meet the need. Generalized human ECG and arterial BP waveforms were used in this system to expand its usable ranges. From the time course graph plotting, the variation trend of each parameter during each drug-induced transient period was obtained thereafter. The main advantages of this system include: (1) transient analysis
ISSN:0031-7012
DOI:10.1159/000138921
出版商:S. Karger AG
年代:1992
数据来源: Karger
|
6. |
Effects of Adrenoceptor Agonists and Antagonists on Cardiovascular Functional Parameters in Rats |
|
Pharmacology,
Volume 44,
Issue 4,
1992,
Page 225-236
M.S. Young,
K.W. Lin,
M.T. Lin,
Preview
|
PDF (1695KB)
|
|
摘要:
The effects of intravenous administration of adrenoceptor agonists and antagonists on electrocardiographic or blood pressure (BP) functional parameters were assessed in urethane-anesthetized rats. The responses of cardiovascular functional parameters produced by these drugs included: (1) isoproterenol decreased the duration of a whole BP cycle (Wd), duration of the diastolic wave (Dd), peak amplitude of the systolic wave (SYa), amplitude of the diastolic notch (DNa), amplitude of the diastolic wave (DWa), pulse pressure (dp) and mean arterial pressure (mp) but increased the heart rate (HR) accompanied by prolonged R-R (RR) or P-P interval (PP) (2) propranolol decreased SYa, DNa, dp, mp, HR, the amplitude of the P wave (Pa) and amplitude of the S wave (Sa) but increased the duration of the QRS wave, P-R interval, duration of the R wave (Rd) and duration of the P wave (Pd); (3) adrenaline decreased HR (accompanied by prolonged RR and PP), Rd, Pa and amplitude of the T wave (Ta) but increased Pd, Wd, Dd, DNA, the time interval between aortic valve opening and closure (Dw), dp, mp, amplitude of the Q wave and amplitude of the R wave (Ra); (4) noradrenaline decreased HR (accompanied by prolonged RR and PP) and Pa but increased Wd, Pd, SYa, DNa, Dw, dp, mp, Ra and Ta; (5) phenylephrine decreased HR (accompanied by prolonged RR and PP) and Pa but increased Wd, Dd, DNa, mp and Ra; (6) phentolamine decreased SYa, DNa, DWa, Dw, dp and mp. This study illustrates the utility of the automated electrocardiogram (ECG) and BP analysis system for investigation of adrenoceptor agonists and antagonists. The use of this methodology not only reproduced most of cardiovascular functional parameter effects produced by these drugs using the conventional methodology but also realizes some new information about the drug-induced ECG or BP waveform effects.
ISSN:0031-7012
DOI:10.1159/000138922
出版商:S. Karger AG
年代:1992
数据来源: Karger
|
|