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Biomedical subjects

G Bassotti

Publications and source records attributed to G Bassotti.

At least 127 records · Page 7Linked to original sources
PubMed1989

Involvement of different mechanisms in the stimulatory effects of cholecystokinin octapeptide on gastrointestinal and colonic motility in dogs.

The effects of an intravenous infusion of cholecystokinin octapeptide (CCK-8, 1 microgram.kg-1.h-1) were investigated in conscious fasted dogs chronically fitted with strain-gauge transducers on the antrum, the jejunum, and the colon. Attempts to antagonize the increase of motility appearing at the three levels during CCK infusion were made using different blockers to elucidate the mechanisms involved. Asperlicin (a specific CCK antagonist) blocked the effects of CCK-8 at the three levels, while atropine and somatostatin were only effective in the jejunum and colon. Methyl-levallorphan (a mu-opiate antagonist that poorly crosses the blood-brain barrier) antagonized the CCK-induced colonic stimulation when intracerebroventricularly administered. Serotonin, histamine, substance P, and K-antagonists as well as a benzodiazepine did not modify the CCK-8 induced stimulation. It was concluded that the stimulatory effect of CCK-8 resulted from (a) a direct stimulation of the smooth muscle cells at gastric level, (b) a cholinergic activation of the jejunum and the colon, and (c) the involvement of a mu-opioid central component in the colonic response only.

Animals↗
PubMed1989

Functional gut disorders and health care seeking behavior in an Italian non-patient population.

We conducted a survey on functional gut disorders and health care seeking behavior in a large non-patient population of an Italian region (Umbria). 533 subjects were interviewed by means of a specific questionnaire. 44 (8.5%) reported symptoms compatible with the irritable bowel syndrome, 30 (5.8%) had non-colonic pain, 48 (9.2%) chronic constipation, and 20 (3.8%) dyspepsia. It is concluded that in our region there is a relatively high percentage of subjects that do not commonly seek health care, although affected by functional gut disorders.

Adult↗
PubMed1989

Colonic motor response to eating: a manometric investigation in proximal and distal portions of the viscus in man.

The motor response of the human colon to a meal is still poorly characterized. Such data as are available were obtained chiefly for the distal colonic portions with myoelectrical techniques. For these reasons, we investigated proximal and distal colonic motor responses to food ingestion in a rather large group of healthy subjects. Twenty-nine healthy volunteers were studied with a colonoscopically positioned multilumen manometric probe and low-compliance infusion system. Recordings were obtained for 2 h during fasting and for 3 h after the subjects had eaten a 1000-kcal standard mixed meal. During fasting, motility was quite low, and no significant differences between proximal and distal portions were seen. After eating, each portion significantly increased its motor activity throughout the subsequent recording period, but there were differences in the time course in the response to eating for different colonic segments. Proximal portions (especially the transverse colon) had first a sudden maximal increase and then a decrease, whereas the distal ones had a slower and more sustained increase in activity. These findings are of interest, especially for comparison with those of patients with suspected motor dysfunction of the large bowel.

Adult↗
PubMed1988

A new criterion for selection of pharmacokinetic multiexponential equations.

In linear pharmacokinetics, the time course of the plasma concentration of a drug, Ct, is expressed by the sum of exponential terms, (formula; see text) This article proposes a new statistical criterion for discriminating between alternate polyexponential models. According to this new criterion, the model that best interprets a set of experimental data points is that which minimizes the area between the approximate confidence limits of Ct.

Doxorubicin↗
PubMed1988

Colonic mass movements in idiopathic chronic constipation.

As relatively little is known of human colonic motor activity either in health, or in pathological conditions, we investigated mass movements in 14 chronically constipated patients and 18 healthy volunteers. Mass movements were recorded from proximal and distal colon during 24 h (12 noon-12 noon) by a colonoscopically positioned multilumen manometric probe and low compliance infusion system. Patients and controls differed significantly in the number (mean 2.6 (0.7) v 6.1 (0.9) (SE), p = 0.02) and duration (mean 8.2 (1.6) v 14.1 (0.8) s, p = 0.04) of mass movements. The data suggest that one pathophysiological mechanism of constipation may be decreased propulsive activity. A circadian pattern, with a significant difference between day and night distribution, was documented in both groups. The patients reported decreased defecatory stimulus concomitant with the mass movements.

Adult↗
PubMed1988

Manometric investigation of high-amplitude propagated contractile activity of the human colon.

The motor activity of colonic segments proximal to the rectosigmoid junction are poorly understood. We investigated colonic peristalsis (high-amplitude propagated contractions; HAPCs) in 20 healthy volunteers by means of a colonoscopically positioned manometric probe and low-compliance infusion system. In all, 110 HAPCs were recorded from the ascending, transverse, descending, and sigmoid colon, and their features and daily distribution were analyzed and characterized. Mean frequency was 6.1 +/- 0.9 (SE) per subject per 24 h, mean amplitude was 110.37 +/- 6.3 mmHg, mean duration was 14.15 +/- 0.8 s, and mean propagation velocity was 1.11 +/- 0.1 cm/s. There were no significant differences among colonic segments. Diurnal changes of HAPCs were also noted, with a maximum frequency after meals and after awakening in the morning, and a minimum recorded in the late afternoon and during the night. These HAPCs may represent the manometric equivalent of mass movements.

Adult↗
PubMed1988

Oesophageal motor activity in rheumatoid arthritis: a clinical and manometric study.

Oesophageal motor function was clinically and manometrically investigated by means of a low-compliance system in 24 nonselected rheumatoid arthritis (RA) patients and 15 healthy controls. Dysphagia was referred by 37.5% of RA patients. Oesophageal motor abnormalities were discovered to be significantly present in a high percentage (62.5%) of patients with RA. However, there was no correlation between oesophageal motor abnormalities and any disease characteristic. It is concluded that a high percentage of RA patients have an oesophageal motor dysfunction, even in the absence of dysphagic symptoms.

Arthritis, Rheumatoid↗
PubMed1988

Manometric evaluation of cimetropium bromide activity in patients with the nutcracker oesophagus.

There are at present few therapeutic alternatives to calcium channel blockers for the medical treatment of patients with nutcracker oesophagus. For this reason, we evaluated by means of a low-compliance manometric system the effect of a new anticholinergic compound, cimetropium bromide (10 mg intravenously), on oesophageal variables of eight patients with nutcracker oesophagus, in a single-blind study. Eight age-matched healthy volunteers served as controls. In both patients and controls, cimetropium bromide significantly decreased lower oesophageal sphincter pressure and the distal and proximal mean contraction amplitude of the oesophageal body. Apart from an increase in pulse rate, no noteworthy side effects were observed. It is concluded that cimetropium bromide may be an effective therapeutic option in patients with nutcracker oesophagus.

Adult↗
PubMed1987

Twenty four hour manometric recording of colonic motor activity in healthy man.

The motor activity of the transverse, descending, and sigmoid colon was recorded for 24 hours in 14 healthy volunteers with a colonoscope positioned catheter. During the study the patients ate two 1000 kcal mixed meals and one continental breakfast. Colonic motor activity was low before meals and minimal during sleep; the motility index increased significantly after meals and at morning awakening. Most of the motor activity was represented by low amplitude contractions present singly or in bursts, which showed no recognisable pattern. All but two subjects also showed isolated high amplitude (up to 200 mmHg) contractions that propagated peristaltically over long distances at approximately 1 cm/sec. Most of these contractions occurred after morning awakening, and some in the late postprandial period, with a mean of 4.4/subject/24 h. The peristaltic contractions were often felt as an urge to defecate or preceded defecation, and could represent the manometric equivalent of the mass movements.

Adult↗
PubMed1987

Transverse and sigmoid colon motility in healthy humans: effects of eating and of cimetropium bromide.

There have been few studies of the motility of the colon proximal to the rectosigmoid area. For this purpose we evaluated (1) fasting and postprandial transverse and sigmoid colon motor activity and (2) the effects of a new nonselective anticholinergic drug, cimetropium bromide, on transverse and sigmoid motor responses to eating. Two paired studies were carried out in 11 healthy volunteers by means of a colonscopically positioned manometric probe. After placebo, eating significantly increased transverse and sigmoid motility indices throughout the recording period. Cimetropium significantly reduced the motor responses to eating in both the transverse and the sigmoid colon.

Adult↗
PubMed1986

Colonic motility and gastric emptying in patients with irritable bowel syndrome. Effect of pretreatment with octylonium bromide.

This study was undertaken to evaluate (1) the colonic response to eating for a prolonged time in healthy subjects and patients with the irritable bowel syndrome (IBS); (2) the effect of octylonium bromide, a new smooth muscle relaxant acting by interfering with calcium ion mobilization, on the postprandial colonic motility; and (3) whether chronic gastric stasis could be responsible for both the dyspeptic symptoms often complained of by IBS patients and the faulty colonic response to eating. The colonic response to a 1000-kcal mixed meal in ten healthy subjects was characterized by two transient (from 0 to 60 and from 120 to 150 min postprandially, respectively) increases in colonic motor activity; ten IBS patients showed a continuous postprandial increase in colonic motor activity that was not terminated 180 min after eating. Treatment of IBS patients with octylonium bromide (80 mg, qid, per os) for 5-7 days reduced their colonic response to eating to a very short increase in colonic motor activity limited to the first 30 min. Finally, gastric emptying was not different in the two groups.

Adult↗
PubMed1986

Functional dyspepsia and chronic idiopathic gastric stasis. Role of endogenous opiates.

Chronic idiopathic gastric stasis can be responsible for unexplained dyspepsia. Because exogenous opiates inhibit gastric emptying and endogenouslike substances are present in the gastrointestinal tract, we tested the hypothesis that increased endogenous opiate activity may be responsible for chronic idiopathic gastric stasis. Eighteen patients with chronic idiopathic gastric stasis and ten healthy volunteers were studied by gastrointestinal manometry. Scintigraphic technique also was used, during which either intravenous saline or naloxone hydrochloride were infused. Manometry showed gastric hypomotility in ten patients and duodenal hyperdyskinesia in the remaining eight patients. Naloxone did not alter gastric emptying in healthy subjects or corrected gastric stasis in patients with gastric hypomotility, while it normalized gastric emptying in patients with duodenal dyskinesia. It seems that either gastroparesis or duodenal dyskinesia can promote gastric stasis and chronic dyspepsia, and endogenous opiates participate in the pathogenesis of gastric stasis in patients with duodenal dyskinesia.

Adult↗
PubMed1985

Identification of muscarinic receptor subtype mediating colonic response to eating.

The colonic motor response to eating requires cholinergic transmission. Recent studies have identified two subclasses of muscarinic receptor, the M1 and the M2 subtype. The aim of this study was to evaluate the muscarinic receptor subtype responsible for mediating the gastrocolonic response. Spike potential (SP) activity and intraluminal pressure were recorded, during fasting and after eating a 1000-kcal mixed meal, from the distal colon of 10 healthy volunteers. In each subject three paired studies were carried out: either atropine (a nonselective antimuscarinic, 1 mg), pirenzepine (a selective M1 antimuscarinic, 10 mg), or saline were infused intravenously before eating, using a double-blind crossover design. The meal significantly increased colonic spike potential activity (17.6 +/- 3.9, SP/30 min) above fasting values (2.7 +/- 0.6, P less than 0.01) in the control study. There was no postprandial increase in spike potential activity (3.3 +/- 0.9, SP/30 min) after atropine. The meal also significantly increased spike potential activity (15.4 +/- 3.3 SP/30 min, P less than 0.01) above fasting levels and equal to that of the controls, in the pirenzepine study. These data suggest that the colonic motor response to eating is mediated through the M2 but not the M1 subtype of muscarinic receptors.

Adult↗