Effects of some synthetic kynurenines on brain amino acids and nitric oxide after pentylenetetrazole administration to rats

We have previously proven that some synthetic kynurenines behave as antagonists of the N-methyl-d-aspartate receptor inhibiting neuronal subtype of nitric oxide synthase activity. We now investigate the anticonvulsant activity of four of these kynurenines in pentylenetetrazole (PTZ)-treated rats. The rats were treated with each kynurenine (10-160 mg/kg, s.c.) 30 min before PTZ administration (100 mg/kg, s.c.). Then, latency, duration and intensity of the first seizure and the percent animal survival were noted. PTZ-induced death was counteracted by high doses of kynurenines. Latency of the first seizure was significantly increased and its intensity reduced at the same doses, whereas the duration of the first seizure significantly decreased with doses of 20 mg/kg in most of the kynurenines tested. Three hours after PTZ administration, the surviving animals were sacrificed and the levels of brain amino acids and nitrite were measured. PTZ administration increased glutamate, glutamine, serine and taurine levels in different brain areas. High doses of kynurenines generally counteracted the effects of PTZ on excitatory amino acids, but they also reduced inhibitory aminoacids. However, the most consistent effect of kynurenines was the dose-dependent reduction of brain nitrite levels induced by PTZ. These results reveal a new family of anticonvulsant drugs that affect mainly to nitric oxide production in the brain.     

Development of brain damage after neonatal hypoxia-ischemia: Excitatory amino acids and cysteine

The aim of this study was to investigate the possible role of excitatory amino acids (EAAs) and cysteine in the development of brain damage after hypoxia-ischemia (HI) in neonates. In a rat model of neonatal HI, changes in extracellular (ec) amino acids in cerebral cortex were measured with microdialysis and correlated with the extent of brain damage at the site of probe placement. Extracellular concentrations of glutamate, aspartate and cysteine increased during HI and remained elevated during reperfusion. During HI the pattern of EAA changes was the same in the infarcted, undamaged and border zone regions. During reperfusion, however, the ec concentrations of glutamate, aspartate and cysteine were higher in infarcted and border zone areas compared to undamaged tissue. HI also produced a slight increase of tissue concentration of cysteine and decrease of tissue concentration of glutamate in parietal cortex of the HI hemisphere. The effect of cysteine on brain damage induced by HI and glutamate was also investigated. A subtoxic dose of cysteine potentiated glutamate toxicity in the arcuate nucleus and enhanced brain infarction after HI in neonatal rats. The results show that in neonatal HI the extracellular levels of EAAs during HI are not directly related to brain injury but the EAA levels during reflow predict the extent of infarction. Cysteine increases HI-induced brain injury and potentiates glutamate toxicity in neonatal rats. Speculatively, elevated level of cysteine during reperfusion may participate in the excitotoxic cascade leading to brain injury.     

Effects of intravenous infusion of amino acids on cholecystokinin release and gallbladder contraction in humans

We investigated the effect of intravenous infusions of the therapeutically available amino acid solutions Moripron and Morihepamin (Roussel Morishita, Osaka, Japan) on gallbladder contraction and cholecystokinin (CCK) release in healthy male volunteers. Plasma CCK levels were measured by radioimmunoassay, using the antibody OAL-656, which is specific for the aminoterminus of CCK-8 and thus recognizes biologically active forms of all CCKs. The volume of the gallbladder was calculated by ultrasonographic measurements. Intravenous infusion of Moripron at the rate of 3.33 ml/min for 60 min, caused gallbladder contraction, with a peak response of 31.3±8.6% of the fasting volume at 45–60 min, and a significant increase in plasma CCK concentration, from 1.8±0.2 pmol/l to a peak of 9.9±1.5 pmol/l, at 30–45 min. The maximum gallbladder contraction and the peak CCK release during the Moripron infusion were not significantly different from findings after a test meal. There was a close relationship between the peak plasma CCK concentration and the maximal gallbladder contraction during the administration of Moripron, and this agent, even when infused at the rate of 1.67 ml/min, significantly increased plasma CCK levels and gallbladder contraction. Intravenous infusion of Morihepamin had no significant influence on gallbladder volume or plasma CCK levels. The discrepancy in responses appeared to be related to differences in composition between Moripron and Morihepamin, and not to the total dose of amino acid. Intravenous infusions of amino acids appear to have different effects on gallbladder contraction and plasma CCK secretion depending on the amino acids composition. Our findings suggest that an intravenous infusion of Moripron could be used for the prophylaxis of acute acalculous cholecystitis and sludge formation due to reduced biliary motility in patients on total parenteral nutrition.     

Effects of truncal vagotomy and antrectomy on bombesin-stimulated pancreatic secretion,release of gastrin,and pancreatic polypeptide in the anesthetized dog

The short-term effects of truncal vagotomy and antrectomy on bombesin-stimulated pancreatic secretion and release of gastrin and pancreatic polypeptide (PP) were studied in 18 anesthetized dogs. Together with an intravenous infusion of secretin (250 ng/kg/hr) bombesin (500 ng/kg/hr) was given before and after truncal vagotomy, antrectomy, and sham operation (N=6 dogs per group). Peak incremental pancreatic protein output in procedures (tachyphylaxis). Neither truncal vagotomy nor antrectomy significantly altered the pancreatic protein response to bombesin when compared with sham operation. Bombesin produced a mean 1-hr increase over basal of 196 pM for gastrin, which was abolished by antrectomy but not appreciably affected by truncal vagotomy and sham operation. The mean 1-hr increment (207 pM) for PP in response to bombesin was not changed by truncal vagotomy, antrectomy, and sham operation. This study shows in the anesthetized dog that exogenous bombesin stimulates release of PP as well as gastrin; that the release of gastrin by bombesin is not vagally dependent; that neither truncal vagotomy nor antrectomy alter the release of PP by bombesin; and that the action of bombesin on pancreatic protein secretion does not depend on release of gastrin or on intact vagal nerves.Parts of this paper have been presented at the 12th European Pancreatic Club Meeting, Copenhagen, Denmark, October 11–13, 1979, and at the 3rd International Symposium on Gastrointestinal Hormones, Cambridge, England, September 15–18, 1980.     

Gastric emptying for solids in patients with duodenal ulcer before and after highly selective vagotomy

In a series of 31 duodenal ulcer patients (23 males and 8 females), who underwent a highly selective vagotomy, gastric emptying characteristics of a solid meal, labeled with [su99mTc]stannous colloid, were assessed before, two weeks and six months after operation. The clinical diagnosis was confirmed by endoscopy and x-ray; failure of treatment with H₂ antagonists or antacids during 1–18 (mean 5) years was the direct indication for operative treatment. A temporary delay in gastric emptying is noted two weeks after operation (T 1/2: 124 vs 57 min). After six months, gastric emptying time has practically normalized. It appears that this is the result of the preservation of the antropyloric vagal nerve supply. In these patients, a 10% recurrence rate is noted, comparable to the results in the literature. Highly selective vagotomy proves to be a safe and effective procedure with few side effects. It does not impair gastric motility.     

Free amino acids in congestive heart failure

Free amino acids were quantitatively analyzed in cardiac muscle and plasma of dogs with chronic congestive heart failure produced by progressive pulmonary artery stenosis. Right ventricular systolic pressure increased from 32 to 89 mmHg and right ventricular end diastolic pressure from 3 to 15 mmHg following chronic constriction of the pulmonary artery. The ratio of right to left ventricular weight approximately doubled (30% vs. 63%) while percent dry weight (21%) did not change in failing hearts. The concentration of plasma and left ventricular amino acids were the same in control and experimental animals. The total free amino acid pool of the failing right ventricle appeared to increase and a significant alteration was seen in methionine concentration (0.111 ± 0.047 vs. 0.523 ± 0.081 μmol/g dry weight). A large change was found in the concentration of taurine (2-aminoethanesulfonic acid) in right ventricles (32.8 ± 3.4 vs. 126 ± 10 μmol/g dry weight) while the same compound was not altered in left ventricles. Myocardial free amino acid metabolism, as judged by endogenous concentrations, was not greatly influenced by chronic heart failure although failing right ventricles seemed to have an expanded pool. Specifically, the large increase in taurine concentration, which was confined to the failing right ventricle, may have functional significance since this compound has been linked to cellular calcium ion movement.     

Aromatic and branched-chain amino acids in autopsied brain tissue from cirrhotic patients with hepatic encephalopathy

Concentrations of the branched-chain amino acids (BCAAs) valine, leucine, and isoleucine and the aromatic amino acids (AAAs) phenylalanine and tyrosine were measured in three areas of dissected brain tissue obtained at autopsy from nine cirrhotic patients who died in hepatic encephalopathy. The controls were an equal number of subjects free from neurological, psychiatric or hepatic diseases, matched for age and time interval from death to freezing of autopsied brain samples. Amino acids were measured using high-performance liquid chromatography with fluorimetric detection. In brain tissue of cirrhotic patients, no changes in BCAA concentrations were observed compared with controls. On the other hand, phenylalanine levels were found to be increased 141% in prefrontal cortex, 86% in frontal cortex and 26% in caudate nucleus, and tyrosine content was increased by 71% in prefrontal cortex and 28% in frontal cortex with no significant increase in caudate nucleus. Alterations in the concentration of AAAs may lead to disturbances of monoamine neurotransmitters in brain. Such changes could play a role in the pathogenesis of hepatic encephalopathy resulting from chronic liver disease in man.     

Co-localization of islet amyloid polypeptide and insulin in the B cell secretory granules of the human pancreatic islets

Summary Islet amyloid polypeptide is a novel 37 amino-acid-residues polypeptide which has been isolated from amyloid deposits in an insulinoma, and in human and cat islets of Langerhans. The molecule has 46% homology with the calcitonin gene-related peptide. Light microscopy examination of the pancreas shows that islet amyloid polypeptide immunoreactivity is restricted to the islet B cells. The present study utilized a rabbit antiserum against a synthetic peptide corresponding to positions 20–29 of islet amyloid polypeptide, a sequence without any amino-acid identity with calcitonin gene-related peptide. By applying the immunogold technique at the ultrastructural level, it was shown that both insulin and islet amyloid polypeptide immunoreactivity occurs in the central granular core of the human B cell secretory granules, while the A cells remain unlabelled. The demonstration that islet amyloid polypeptide is a granular protein of the B cells may indicate that it is released together with insulin. Further studies are necessary to evaluate the functional role of islet amyloid polypeptide.     

An apparent inhibition of insulin biosynthesis resulting from inhibition of transport of neutral amino acids by arginine

Summary At concentrations higher than 10 mM, the cationic amino acid, arginine, inhibited the incorporation of the neutral amino acids such as alanine, threonine, valine and leucine into insulin in the presence of glucose. This inhibitory effect probably did not result from the stimulatory effect of arginine on insulin release because, in the absence of glucose, arginine failed to stimulate insulin release but nevertheless inhibited the incorporation of leucine into insulin. This inhibitory effect of arginine was shared by another basic amino acid, histidine, but not by lysine. Arginine inhibited the incorporation of leucine not only into insulin but also into other islet proteins. This inhibition was not accompanied by any disturbance of glucose metabolism in the islet cells. Further studies indicated that the inhibition of incorporation resulted primarily from the interference of uptake of the neutral amino acids by arginine.     

Pancreatic polypeptide response to a meal before and after cutting the extrinsic nerves of the upper gastrointestinal tract and the pancreas in the dog

The role of the sympathetic and parasympathetic innervation in the release of pancreatic polypeptide (PP) basally and in response to a meal was studied after stepwise extrinsic denervation of the pancreas and the upper gastrointestinal tract in conscious dogs with gastric fistulae. One set of seven dogs was fed a meat meal (35 g/kg body weight) before and after truncal vagotomy and after truncal vagotomy plus celiac and superior mesenteric ganglionectomy, ie, extrinsic denervation of the pancreas and the upper gastrointestinal tract. In another set of six dogs, only ganglionectomy was performed. Experiments were repeated in the presence of atropine (50 g/kg body weight, given as an intravenous bolus 60 min prior to the meal). Truncal vagotomy significantly (P<0.05) reduced the postprandial 120-min integrated plasma PP response (IPPPR) by 84% as compared to the prevagotomy response. Before truncal vagotomy, atropine significantly reduced the IPPPR by 57%. After truncal vagotomy, atropine completely abolished the residual PP response. Additional celiac and superior mesenteric ganglionectomy did not alter the IPPPR already reduced by truncal vagotomy. With the vagus nerves intact, ganglionectomy alone had no effect on the IPPPR whether or not atropine was given. These findings indicate that (1) the splanchnic nerves do not play a significant role in postprandial PP release and (2) that the vagus nerves are important mediators of the response to a meal. The effect of atropine on postprandial PP release after truncal vagotomy may be due to interruption of short enteropancreatic reflexes, suppression of the intrinsic cholinergic activity of the pancreas, or inhibition of hormonally induced PP release.     

Effects of highly selective vagotomy on gastric myoelectrical activity

Changes in gastric myoelectrical activity following highly selective vagotomy were studied in 12 patients by means of electrogastrography (EGG) using cutaneous electrodes. Measurements were made before, 10 days after, and six months after operation. Eight patients undergoing cholecystectomy served as controls. Preoperatively all controls and patients had normal recordings. In the cholecystectomized patients no significant changes were found postoperatively. Ten days after highly selective vagotomy the normal initial postprandial dip in gastric ECA frequency and the subsequent increase in frequency and power were not seen. Tachygastrias were observed in three patients. Six months after operation the normal frequency and power responses to a test meal had returned, but both the fasting and postprandial ECA frequencies were raised significantly. It is concluded that highly selective vagotomy is associated with abnormalities in myoelectrical activity, in particular in the postprandial state, most of which are reversible with time.     

肌氨肽苷联用甲钴胺治疗糖尿病周围神经病变的疗效观察

目的 探讨肌氨肽苷联用甲钴胺治疗糖尿病周围神经病变的临床效果.方法 86例糖尿病周围神经病变患者随机分为对照组（44例）和研究组（42例）,在一般治疗的基础上研究组给予甲钴胺和肌氨肽苷联合治疗,对照组仅用甲钴胺治疗;比较两组的临床疗效.结果 与对照组比较,研究组症状、体征以及神经传导速度明显改善,糖化血红蛋白明显降低,降钙素基因相关肽明显升高.结论 肌氨肽苷联合甲钴胺治疗糖尿病周围神经病变有显著疗效.     

肌氨肽苷治疗不稳定型心绞痛的疗效

目的:评价肌氨肽苷注射液对不稳定型心绞痛的疗效。方法:80例不稳定型心绞痛患者随机分为两组,治疗组:以肌氨肽苷8ml加入5%葡萄糖液250ml中静滴治疗;对照组:以硝酸甘油(NTG)20mg加入5%葡萄糖液250ml中静滴治疗。结果:肌氨肽苷组临床疗效总有效率95.2%,NTG组总有效率73.7%(P<0.05)。两组均能减小二项乘积(RPP,收缩压×心率)及ECG的∑ST(P<0.05),但肌氨肽苷组减少∑ST更著(P<0.05),且肌氨肽苷能改善左室射血分数等心功能指标(P<0.05)。结论:肌氨苷比NTG更有效地改善不稳定型心绞痛患者的症状,心电图缺血和心功能。     

Plasma pancreatic polypeptide levels are associated with differences in body fat distribution in human subjects

Aims/hypothesis Pancreatic polypeptide (PP) is produced by the F-cells of the pancreas, and its plasma concentration has been used as a marker of parasympathetic activity. Recent work in rodents suggests that there is both sympathetic and parasympathetic innervation of white adipose tissue and that parasympathetic activity is anabolic resulting in lipid accumulation. We have examined whether in humans increased PP levels are associated with increased intra-abdominal fat (IAF), and thereby insulin resistance. Materials and methods We measured PP levels in 177 non-diabetic subjects (75 male/102 female; age 32–75 years) 3 min after an i.v. glucose bolus during a frequently sampled intravenous glucose tolerance test. IAF and s.c. fat (SCF) areas were measured by CT scan. The insulin sensitivity index (S _I) was quantified using Bergman’s minimal model. Results PP levels were higher in men than in women (96.2 ± 72.2 vs 76.1 ± 55.0 pg/ml, mean ± SD, p = 0.037), as was IAF area (124.7 ± 67.4 vs 83.0 ± 57.7 cm², p < 0.001). While PP levels were significantly associated with IAF (r = 0.16, p = 0.031), WHR (r = 0.30, p < 0.001) and age (r = 0.37, p < 0.01), they were not associated with SCF (r = 0.02, p = 0.829). The association between PP and IAF was not independent of age and/or sex. S _I was negatively associated with PP levels (r = −0.17, p = 0.026) and IAF area (r = −0.65, p < 0.001). The association between S _I and PP disappeared after adjusting for IAF area, indicating that S _I was not a major determinant of PP levels. Conclusions/interpretation In humans, age and sex may modulate the association between plasma PP level and IAF area, suggesting that they may be determinants of parasympathetic activity and thus IAF accumulation.     

Pancreatic polypeptide secretion after insulin infusion and protein meal in juvenile type 1 diabetic subjects

Summary An impaired pancreatic polypeptide response (PP) after hypoglycemia has been described in type I diabetic patients with overt autonomic neuropathy. Some authors have suggested that PP release might be useful as sensitive indicator of autonomic neuropathy. The meal test is safer and simpler than the insulin infusion test as PP stimulus. The aim of this study was to compare PP response to insulin infusion and protein meal test and to correlate these responses to the presence of measurable neuropathic disturbances. We thus studied 13 IDDM children and adolescents and 6 normal children. In diabetics the PP response to both tests was not different from that of the control subjects, but PP response to insulin infusion was inversely correlated to the duration of illness and was significantly lower in subjects with pathological heart rate response when compared to the control group. PP responses to the two stimuli were not correlated. We suggest that reduced PP response to hypoglycemia is an early sign of autonomic neuropathy as well as impairment of beat-to-beat variation when impaired PP response to meal test is still not evident. This study was supported in part by CNR grant CT87.01555.     

Effects of endogenous and exogenous secretin on plasma pancreatic polypeptide concentrations in dogs

Summary The effects of exogenous and endogenous secretin with or without intravenous glucose infusion upon islet hormone secretion were studied in four conscious mongrel dogs fitted with a duodenal fistula. Intravenous infusion of secretin for 1 h at doses of 0.5 and 4 U/kg raised plasma secretin concentrations to physiological and pharmacological levels respectively, without affecting plasma insulin and pancreatic polypeptide concentrations. In contrast, bolus injections of secretin at high concentrations produced significant increases of plasma insulin at 0.5 U/kg and 4 U/kg and of pancreatic polypeptide at 4 U/kg. Plasma glucagon did not change during intravenous infusion of low dose secretin (0.5 U · kg^–1 · h^–1), but decreased during infusion of 4 U · kg^–1 · h^–1 or bolus injection of secretin (0.5 U/kg). Intravenous infusion of glucose together with secretin (0.5 U/kg and 4 U/kg) did not affecf plasma insulin, glucagon, or pancreatic polypeptide levels significantly compared with the changes caused by glucose infusion alone. Intraduodenal instillation of HCl, which produced plasma secretin concentrations similar to those evoked by intravenous infusion of secretin (4 U · kg ^–1 · h^–1), led to a rise in plasma pancreatic polypeptide. It is concluded that the stimulatory effects of secretin on insulin and pancreatic polypeptide and the inhibitory effect on glucagon are pharmacological, and that increase of plasma pancreatic polypeptide after intraduodenal infusion of HCl is not mediated by endogenous secretin.     

胰淀粉样多肽在糖尿病及胰腺癌患者胰腺组织中的表达

目的 检测胰淀粉样多肽(IAPP)在胰腺癌患者胰腺组织中的表达,探讨胰腺癌与糖尿病的相关性.方法 收集28例手术切除的胰腺癌及其相应癌旁正常胰腺组织,其中12例患者合并糖尿病,16例不合并糖尿病.采用免疫组化和蛋白质印迹法(Western blotting)检测组织标本中IAPP的表达.结果 IAPP定位表达于人胰腺的胰岛细胞胞质内.合并糖尿病的胰腺癌组织及癌旁胰腺组织、不合并糖尿病的胰腺癌组织及癌旁胰腺组织IAPP表达的免疫组化指数分别为283 305±91 627、122 874±86 917、154 032±81 097和105 797±67 593;IAPP相对表达量分别为(173.1±23.5)%、(1 19.4±18.4)%、(148.7±28.3)%和100%.胰腺癌组织的IAPP表达均显著高于相应癌旁正常胰腺组织(P＜0.01);合并糖尿病的胰腺癌组织的IAPP表达显著高于不合并糖尿病的胰腺癌组织(P＜0.01);合并糖尿病的痛旁胰腺组织的IAPP表达高于不合并糖尿病的痛旁胰腺组织(P＜0.05).结论 IAPP与糖尿病及胰腺癌的发病密切相关,很可能为两种疾病的共同发病机制之一.     

Improvement of regional cerebral blood flow after oral intake of ranched-chain amino acids in patients with cirrhosis

AIM: To evaluate the effect of oral intake of branched-chain amino acids (BCAA) on brain perfusion in patients with liver cirrhosis. METHODS: Single photon emission computed tomography scans were performed in 43 patients with cirrhosis and in 15 age-matched healthy subjects. Twenty-nine out of forty-three patients were randomly treated with either BCAA granules or placebo, and single photon emission computed tomography was performed before and after the treatment. We measured the regional cerebral blood flow values using a three-dimensional stereotaxic region of interest template. RESULTS: Cirrhotic patients had regions of significant hypoperfusion in the bilateral central (right P=0.039, P＜0.05; left P = 0.006 P＜0.01), parietal (right P = 0.018, P＜0.05; left P = 0.009, P＜0.01), angular (right P = 0.039, P＜0.05; left P = 0.008, P＜0.01), and left pericallosal segments (P = 0.038 P＜0.05) as compared with healthy subjects. A significant increase in cerebral perfusion was observed 70 min after the oral intake of BCAA in the angular (right P = 0.012, P＜0.05; left P = 0.049, P＜0.05), temporal (right P=0.012, P＜0.05; left P=0.038, P＜0.05), pericallosal segments (right P=0.025, P＜0.05; left P=0.049, P＜0.05) and left precentral (P = 0.044, P＜0.05), parietal (P = 0.040, P＜0.05) and thalamus (P = 0.033, P＜0.05). No significant change in perfusion was observed in the placebo group. CONCLUSION: Administration of BCAA rapidly improves cerebral perfusion.     

Improvement of regional cerebral blood flow after oral intake of branched-chain amino acids in patients with cirrhosis

AIM: To evaluate the effect of oral intake of branched-chain amino acids (BCAA) on brain perfusion in patients with liver cirrhosis.METHODS: Single photon emission computed tomography scans were performed in 43 patients with cirrhosis and in 15 age-matched healthy subjects. Twenty-nine out of forty-three patients were randomly treated with either BCAA granules or placebo, and single photon emission computed tomography was performed before and after the treatment. We measured the regional cerebral blood flow values using a three-dimensional stereotaxic region of interest template.RESULTS: Cirrhotic patients had regions of significant hypoperfusion in the bilateral central (right P=0.039, P<0.05; left P=0.006 P<0.01), parietal (right P=0.018, P<0.05; left P=0.009, P<0.01), angular (right P=0.039, P<0.05; left P 0.008, P<0.01), and left pericallosal segments (P=0.038 P<0.05) as compared with healthy subjects. A significant increase in cerebral perfusion was observed 70 min after the oral intake of BCAA in the angular (right P=0.012, P<0.05; left P=0.049, P<0.05), temporal (right P=0.012, P<0.05; left P=0.038, P<0.05), pericallosal segments (right P=0.025, P<0.05; left P=0.049, P<0.05) and left precentral (P=0.044, P<0.05), parietal (P=0.040, P<0.05) and thalamus (P=0.033, P<0.05). No significant change in perfusion was observed in the placebo group.CONCLUSION: Administration of BCAA rapidly improves cerebral perfusion.     

Erythromycin enhances gastric emptying in patients with gastroparesis after vagotomy and antrectomy

We studied the effect of erythromycin on gastric emptying in nine patients with gastroparesis following truncal vagotomy and antrectomy, and assessed their clinical response to chronic oral erythromycin. Gastric emptying was evaluated using a solid-phase radio-labeled meal. Patients were studied after erythromycin 200 mg intravenously (N=9) and after an oral suspension of erythromycin 200 mg (N=7) each given 15 min after ingestion of the meal. Three parameters of gastric emptying were analyzed: half-emptying time (T1/2), area under the curve, and percent gastric residual at 2 hr. Nine patients were subsequently placed on oral suspension erythromycin 150 mg three times a day before meals (range 125–250 mg three times a day) and symptoms of nausea, vomiting, postprandial fullness, and abdominal pain were assessed before and after erythromycin. Intravenous erythromycin markedly accelerated the gastric emptying (all three parameters studied) of solids (P<0.01) in seven of nine patients with postsurgical gastroparesis [baselineT1/2 154±15 min; after intravenous erythromycin,T1/2 56±17 min (mean ±sem)]. Oral erythromycin enhanced (P<0.05) the gastric emptying rate (T1/2, area under the curve) in five of seven patients (baselineT1/2 146±16 min; after oral erythromycin,T1/2 87±20 min). Of the nine patients who were placed on oral maintenance erythromycin, three showed clinical improvement after two weeks. In summary, erythromycin significantly enhances gastric emptying in many patients with vagotomy and antrectomy-induced gastroparesis; however, only a small subset of patients respond clinically to chronic oral erythromycin.Dr. Belinda Ramirez is in private practice in San Antonio, Texas.