Plasma somatostatin-like immunoreactivity and somatostatin-28 levels in obese men.

Somatostatin (SS) impairs nutrient absorption. It has been suggested that hyposomatostatinaemia may be involved in the pathogenesis of obesity. However, data on postprandial SS-like immunoreactivity (SLI) levels in obese subjects are controversial and the levels of SS-28, the main molecular form of circulating SLI in healthy subjects, have not been determined.

Plasma somatostatin levels in patients with chronic idiopathic intestinal pseudo-obstruction.

Objectives: Somatostatin participates in the control of gut motility. Recently, somatostatin analogs have been proposed as therapeutic agents for chronic intestinal pseudo-obstruction, although the endogenous somatostatin pattern has never been assessed in this syndrome. We aimed to evaluate fasting and postprandial plasma somatostatin levels in patients with chronic idiopathic intestinal pseudo-obstruction (CIIP).

Duodenal mucosa and extracellular cyclic nucleotide pattern in coeliac disease.

This study measured the values of cyclic nucleotides and adenylate and guanylate cyclase activities in duodenal mucosa homogenates to verify if they played a part in coeliac disease. Nine controls, 13 patients who did not receive treatment and nine patients who received treatment were studied. Cyclase activity assays were performed under basal conditions and in the presence of gliadin derived peptides.

Plasma cyclic nucleotide levels in patients with refractory anaemia with excess of blasts.

To verify the clinical usefulness of extracellular cyclic nucleotide determinations as tumour markers in preneoplastic syndromes, plasma cyclic AMP (cAMP) and cyclic GMP (cGMP) levels were monitored in 47 patients with refractory anaemia with excess of blasts (35 RAEB and 12 RAEBt), 20 of whom progressed to acute leukaemia during the observation period. The control group consisted of 45 healthy subjects matched for age and sex. In all groups of patients plasma cAMP levels were within the normal range, whereas plasma cGMP levels were significantly higher than those of normal subjects in both RAEB and RAEBt patients, and increased further when progression to acute leukaemia occurred.

Effect of high doses of somatostatin on adenylate cyclase activity in peripheral mononuclear leukocytes from normal subjects and from acute leukemia patients.

In normal lymphocytes somatostatin non-competitively inhibited basal (ID50 5 x 10(-4) M) and isoproterenol- and forskolin-stimulated adenylate cyclase activity (Ac). In acute leukemia blasts, non-responsive to isoproterenol, forskolin, which activates the catalytic subunit, stimulated and somatostatin inhibited Ac, thus indicating the leukemic enzyme, though defective, retains the inhibitory pathway and catalyst function.