The neural pathways involved in the interactions between urinary bladder and internal anal sphincter (IAS) were studied in anaesthetized spinal cats. Activation of vesical afferents produced in the IAS a reflex increase in the electrical activity and a reflex inhibition of the excitatory responses evoked by stimulation of one hypogastric nerve. Both reflexes are achieved partly in the lumbar spinal cord and partly within the inferior mesenteric ganglion.

Anal Canal↗

PubMedDate not supplied

Cross-talk between cellular signalling pathways suggested by phorbol-ester-induced adenylate cyclase phosphorylation.

Receptor-mediated activation of both adenylate cyclase and phosphatidylinositide hydrolysis systems occurs through guanine nucleotide regulatory proteins and ultimately leads to specific activation of either cyclic AMP-dependent protein kinase A or Ca2+/phospholipid-dependent protein kinase C. Given the remarkable diversity of agents that influence cellular metabolism through these pathways and the similarities of their components, interactions between the two signalling systems could occur. In fact, stimulation of cells with 12-O-tetradecanoyl phorbol-13-acetate (TPA), a phorbol ester that activates protein kinase C, influences hormone-sensitive adenylate cyclase. In some cells TPA induces desensitization of receptor-mediated stimulation of adenylate cyclase, whereas in others, such as frog erythrocytes, phorbol ester treatment results in increased agonist-stimulated as well as basal, guanine nucleotide- and fluoride ion-stimulated adenylate cyclase activities. We show here that TPA produces phosphorylation of the catalytic unit of adenylate cyclase in frog erythrocytes. Moreover, purified protein kinase C can directly phosphorylate in vitro the catalytic unit of adenylate cyclase purified from bovine brain. These results suggest that phosphorylation of the catalytic unit of adenylate cyclase by protein kinase C may be involved in the phorbol ester-induced enhancement of adenylate cyclase activity. In addition to providing the first direct demonstration of a covalent modification of the catalytic unit of adenylate cyclase, these results provide a potential biochemical mechanism for a regulatory link between the two major transmembrane signalling systems.

Adenylyl Cyclases↗

PubMedDate not supplied

Serum IL-2 level in rheumatoid arthritis: correlation with joint destruction and disease progression.

Understanding of T cell dysfunctions in rheumatoid arthritis (RA) may help to elucidate the pathophysiology of this disease. Cytokines determinations may be a promising approach and could represent a simple mean of quantifying RA immunological dysfunctions. In this study, interleukin-2 (IL-2) measurements were performed in sera of 74 RA patients to evaluate the potential use of this method to monitor "disease activity" and/or prognosis. Although the serum IL-2 levels of patients in active disease stage proved to be somewhat lower than those from patients with inactive disease, the difference was not significant. In our study, however, the serum IL-2 concentration was correlated with the circulating immune complexes level. In addition, patients with the highest serum IL-2 levels exhibited the poorest radiological stages and these same patients were often not receiving any disease modifying antirheumatic drugs (DMARD). Our results demonstrate that serum IL-2 level may be elevated in certain RA conditions. A better understanding of this phenomenon, especially the consequences of disease duration, could be of interest in the follow up and the prognosis of the disease.

Antigen-Antibody Complex↗

PubMedDate not supplied

[Phosphoribosylpyrophosphate synthetase anomalies in 2 cases of gout beginning at an early age].

On the basis of a study of the action of phosphoribosylpyrophosphate (PRPP) synthetase (EC 2.7.6.1.) in 22 hyperuricemic and 9 normal subjects, the authors report two cases of gout with anomalies of the kinetics of this enzyme. The anomaly consists of an increase in affinity for inorganic phosphate (iP) in the absence of inhibitors, and a decrease in inhibition by low concentrations of ADP in the presence of iP. These patients show no other anomaly of intraerythrocyte PRPP (dosage and production "in vitro"), hypoxanthine-guanine-phosphoribosyl-transferase and APRTase (overall activity and apparent Km). These two cases of gout are characterized clinically by their early occurrence, appearing in one case in a pre-menopausal woman, their family character and their normal sensitivity to allopurinol.

Adenosine Diphosphate↗

PubMedDate not supplied

[Apical fibrosis in ankylosing spondylitis. Contribution of the mucociliary clearance].

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Adult↗

PubMedDate not supplied

[A new case of gold-induced hepatitis during the treatment of rheumatoid polyarthritis].

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Aged↗