Role of circulating catecholamines in the control of pancreatic polypeptide and gastrin release

Abstract

The influence of circulating catecholamines on the release of pancreatic polypeptide (PP) and gastrin was studied in volunteers. Physical exercise increased plasma epinephrine by 374 +/- 123% and plasma norepinephrine by 167 +/- 30%, but plasma PP concentrations remained unchanged during standardized bicycle ergometry. Immediately after cessation of exercise catecholamine levels decreased rapidly, whereas PP concentrations increased by 55%. In a second series, epinephrine infusion (5, 25, and 75 ng.kg-1.min-1) increased epinephrine levels by 38 +/- 12, 331 +/- 69, and 1229 +/- 131%, respectively, whilst norepinephrine was unaffected. Neither during nor after catecholamine infusion PP secretion was affected. Gastrin release increased by a maximum of 85 +/- 38% (at epinephrine 75 ng.kg-1.min-1). It is concluded, that (1) changes in circulating adrenaline do not significantly influence PP secretion in man; (2) the PP increase immediately following physical exercise cannot be attributed to a rapid fall of catecholamine levels; (3) endogenous catecholamines are of minor importance in the control of gastrin secretion.

Effect of sympathomimetics on gastrin secretion from antral G cells in culture.

“…During the exercise there was a small but nonsignificant increase in plasma gastrin. Ofgreater interest was the fact that when the same volunteers received an infusion ofepinephrine which increased levels to 5 nmol/liter (with unchanged norepinephrine levels) there was a significant rise in plasma gastrin (17). In the present study, 1O-6 M epinephrine was required before a significant increase in gastrin release was observed, which is 1,000-fold greater than the levels observed in the circulation.…”

“…Gastrin antibody CKG2 (MRC Regulatory Peptide Group, Vancouver) was used in the assay at a final dilution of 1:2,500,000. This antibody binds to amino-terminal residues and recognizes gastrin 17 only (1 1 …”

Serum endocan levels in women with restless legs syndrome

“…Patients with RLS may experience complete or partial symptomatic improvement during day hours due to factors such as movement, mental work, excitement, 25 which increase the sympathetic activity 26 , 27 leading to increased cortisol release. In turn, cortisol may enhance the sympathetic nervous system activity through positive feedback mechanisms.…”

Erythromycin effects on gastric emptying, antral motility and plasma motilin and pancreatic polypeptide concentrations in anorexia nervosa.

“…'2 The facts that erythromycin displaces motilin bound to its receptor,34 induces contractions in the gastrointestinal tract through the same mechanism as motilin,35' and displays the same regional and species specificities as motilin,3 suggest that erythromycin acts as a motilin agonist. 47 Moreover, the ability of erythromycin derivatives to displace motilin correlates with their ability to induce contractions,' and for one erythromycin derivative it has been shown in binding experiments that the interaction with motilin was a competitive one.4 As motilin receptors are abundant on the muscle cells of the human gastric antrum and the proximal duodenum,8 erythromycin and its derivatives may constitute a new group of agents, which could be of therapeutic value in patients with disordered gastroduodenal motor function. This is suggested also by preliminary results of studies in, albeit small, numbers ofpatients with such disorders.…”