Morphine promotes phosphorylation of the human delta-opioid receptor at serine 363

After prolonged stimulation, the delta-opioid receptor becomes desensitized by regulatory mechanisms such as receptor phosphorylation, internalization and down-regulation. In this study, we demonstrate that morphine treatment causes phosphorylation of S363 in the C-terminus of the human delta-opioid receptor. Morphine-mediated phosphorylation reached 53+/-8% of maximum deltorphin II-mediated phosphorylation. Phosphorylation of S363 may contribute to delta-opioid receptor desensitization by morphine.     

Inhibitory effects of histamine H4 receptor antagonists on experimental colitis in the rat

The histamine H(4) receptor is a G-protein coupled receptor with little homology to the pro-inflammatory histamine H(1) receptor, expressed on cells of the immune system with hematopoietic lineage such as eosinophils and mast cells. The effects of the recently described highly selective histamine H(4) receptor antagonists JNJ 10191584 and JNJ 7777120 have now been investigated on the acute colitis provoked by trinitrobenzene sulphonic acid over 3 days in the rat. Treatment with JNJ 10191584 (10-100 mg/kg p.o., b.i.d.) caused a dose-dependent reduction in macroscopic damage, inhibition of the TNBS-provoked elevation of both colonic myeloperoxidase and tumour necrosis factor-alpha (TNF-alpha), and a reduction in the histologically assessed increase in mucosal and submucosal thickness and neutrophil infiltration. JNJ 7777120 (100 mg/kg p.o., b.i.d.) likewise reduced the macroscopic injury and the increases in colonic myeloperoxidase and TNF-alpha levels. These findings indicate a pro-inflammatory role for the histamine H(4) receptor in this model and suggest a novel pharmacological approach to the treatment of colitis.     

Acid-base profiling of imatinib (gleevec) and its fragments

The site-specific basicities of imatinib (Gleevec, a new signal transduction inhibitor drug of chronic myeloid leukemia) and two of its fragment compounds were quantitated in terms of protonation macroconstants, microconstants, and group constants by NMR-pH and pH-potentiometric titrations. Sequential protonation of imatinib follows the N(34), N(11), N(31), N(13) order, in which N(11) and N(31) show commensurable basicity, but negligible intramolecular interaction. Fragment compounds include two "halves" of imatinib, and their moiety-specific basicities confirm the NMR-based protonation sequence of the parent compound. NMR-pH profiles, macro- and/or microscopic protonation schemes, and species-specific distribution diagrams are presented. On the basis of these data, imatinib is shown to be predominantly neutral, monocationic, and tricationic at intestinal, blood, and gastric pH, respectively. The molecular hypotheses on imatinib binding to the Bcr-Abl oncogene fusion protein are interpreted at the site-specific level in view of the moiety basicities of imatinib.     

Polymorphism in the promoter region of the apolipoprotein A5 gene is associated with an increased susceptibility for coronary artery disease

Although triglycerides (TG) are a major risk factor for coronary artery disease (CAD), their exact role is still controversial. Recently, a T/C polymorphism in the promoter region of the apoA5 gene at position 1131 has been found that is associated with an increased plasma TG concentration. We investigated the role of this polymorphism in 308 Hungarian patients with CAD referred to coronary bypass surgery, and in 310 controls recruited from the same area. The prevalence of the apoA5-1131C allele was significantly higher among CAD patients than among controls (10.9% versus 5.7%; P < 0.001, Odds ratio (OR) = 1.99 (1.30-3.04)). Controls carrying the rare C allele had in average 23.0% (P < 0.001), subjects with CAD 13.8% (P < 0.001) higher TG levels compared to common allele homozygotes. The polymorphism was not associated with other conventional CAD risk factors or laboratory data of the patients. In logistic regression models adjusted for age, gender, presence of diabetes, BMI, smoking, LDL-C, HDL-C and hypertension a significantly increased risk of developing CAD was found in patients carrying the apoA5-1131C allele (P < 0.001; OR = 1.98 (1.14-3.48)), suggesting that this allele variant is an independent genetic risk factor for CAD.     

Relapsing polychondritis

Relapsing polychondritis (RP) is a rare multisystem autoimmune disease of unknown origin characterized by recurrent episodes of inflammation and progressive destruction of cartilaginous tissues. Elastic cartilage of the ears and nose, hyaline cartilage of peripheral joints, vertebral fibrocartilage and tracheobronchial cartilage, as well as proteoglycan-rich structures of the eye, heart, blood vessels or inner ear may all be affected. In most patients RP manifests in a fluctuating but progressive course which eventually results in a significant shortening of life expectancy. The relatively uncommon occurrence, the unknown etiopathogenesis, the ambiguous clinical pattern, as well as the variety in its course and response to therapy may all contribute to the difficulties the physician must overcome when managing RP. Beside describing the main features of RP and seven clinical cases of our own, in the present review we focus on recent findings in the etiopathogenesis and novel treatment options.     

Face-sensitive cortical processing in early infancy

BACKGROUND: Debates about the developmental origins of adult face processing could be directly addressed if a clear infant neural marker could be identified. Previous research with infants remains open to criticism regarding the control stimuli employed. METHODS: We recorded ERPs from adults and 3-month-old infants while they watched faces and matched visual noise stimuli. RESULTS: We observed similar amplitude enhancement for faces in the infant N290 and adult N170. In contrast, the infant P400 showed only a latency effect, making it unlikely to be the main precursor of the adult N170. CONCLUSIONS: We conclude that there is some degree of specificity of cortical processing of faces as early as 3 months of age.     

ATP and ATPase secretion by exocrine pancreas in rat, guinea pig, and human

ATP is an extracellular regulator in numerous physiological and pathologic processes. Recently, 7 different subtypes of purinoceptors were identified on either the basolateral or the luminal membrane of pancreatic duct cells. However, the in vivo regulatory role of ATP in pancreatic function has not been established. We investigated the possible regulatory role of endogenous ATP in pancreatic function by measuring ATP concentrations and ATPase activity in pancreatic juice obtained from anesthetized rats and guinea pigs and from human patients undergoing endoscopy. Juice was collected from the main pancreatic duct in rats and guinea pigs under basal conditions or during stimulation with CCK, bombesin, or secretin. In guinea pigs, CCK, bombesin, and secretin did not affect ATP output, although they did stimulate fluid secretion. ATPase activity in the juice was evaluated by measuring the rate of hydrolysis of added ATP. Consistent with the low ATP concentrations in rat pancreatic juice, we found high levels of ATPase activity in this species. This was confirmed by HPLC, which also showed the metabolites of ATP hydrolysis. Ecto-ATPase activity was demonstrated by enzyme histochemistry in both the pancreatic acini and ducts in rats, but it was not detectable in guinea pigs and humans. These differences in ATP levels and ATPase expression may indicate significant species differences in the purinergic regulation of pancreatic secretion.