SUMMARYUsing a C-terminally directed pancreatic polypeptide (PP) antiserum and immunocytochemical methods, PP-immuno-reactivity (IR) was localized throughout the central (CNS) and peripheral nervous systems (PNS) of the cestode, Moniezia expansa. In the CNS, immunostaining was evident in the paired cerebral ganglia (primitive brain), connecting commissure, and the paired longitudinal nerve cords that are cross-linked by numerous regular transverse connectives. The PNS was seen to consist of a fine anastomosing nerve-net of immunoreactive fibres, many of which were closely associated with reproductive structures. Radioimmunoassay of this peptide IR in acid-alcohol extracts of the worm measured 192·8 ng/g of PP–IR. HPLC analyses of the M. expansa PP–IR identified a single molecular form which was purified to homogeneity. Plasma desorption mass spectrometry (PDMS) of purified parasite peptide resolved a single peptide with a molecular mass of 4599±10 Da. Automated gas-phase Edman degradation identified a 39-amino acid peptide with a C-terminal phenyl-alaninamide. Examination of its primary structure shows that it displays significant sequence homology with the vertebrate neuropeptide Y superfamily, suggesting that this platyhelminth-derived peptide is the phylogenetic precursor. Neuropeptide F (M. expansa) is the first regulatory peptide to be fully sequenced from the phylum Platyhelminthes and may represent a member of an important new class of invertebrate neuropeptide.

A wide variety of neuroendocrine tumours express somatostatin receptors, and can be visualized by radiolabelled somatostatin analogue scintigraphy. To investigate the value of [111In]-octreotide scintigraphy (Octreoscan), 48 patients (37 with proven carcinoid, pancreatic endocrine and medullary carcinoma of thyroid tumours, 11 with neuroendocrine syndromes multiple endocrine neoplasia (MEN-I) and Zollinger-Ellison syndrome (ZES) were examined with 111In-DTPA-D-Phe1-octreotide. Scintigrams were obtained at 24 and 48 h, and the results were compared with CT and magnetic resonance imaging (MRI). Thirty-five of 48 patients had positive [111In]-octreotide scintigraphy (23/25 (92%) carcinoids, 8/9 (89%) PETs, 4/11 (36%) MEN-I & ZES). Of the 42 lesions located by conventional imaging techniques, 37 (88%) were also identified by Octreoscan. Unexpected lesions (40 sites), not detected by CT or MR imaging were found in 24/48 (50%) patients. [111In]-octreotide scintigraphy has a higher sensitivity for tumour detection, and is superior to MR imaging and CT scanning in the identification of previously unsuspected extraliver and lymph node metastases. It may also be helpful for the localization of clinically suspected tumours in patients with MEN-I and ZES.

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Goblet cell carcinoids are uncommon but distinctive tumours of the appendix. We have reviewed 11 cases diagnosed within the period 1976-1990. The mean age at presentation was 58 years (range 24-76), with a female:male ratio of 8:3. At presentation, in seven patients tumour was confined to the appendix or mesoappendix (mean age 51) and in four there was extension beyond the appendix (mean age 69). Of the seven patients with localized tumour, six are alive and without clinical disease after a mean follow-up period of 32 months and one died with recurrent tumour after 10 years. Of the four with more extensive disease, two died during follow-up (at 23 months with probable liver metastases and at 16 months with intestinal obstruction) and two are alive, one with disease and one clinically disease-free. Immunohistochemistry showed that all of the tumours stained positively for either neuron-specific enolase, chromogranin A or protein gene product 9.5. No tumour stained with antiserum to substance P and none showed glucagon-like immunoreactivity, but four cases stained positively for pancreatic polypeptide, an unusual feature in midgut carcinoids.

The distribution of chromogranin A and related peptides in rat tissues was investigated using sequence specific antisera. N- and C-terminal antisera and a presumptive C-terminal rat pancreastatin antiserum immunostained an extensive neuroendocrine cell population throughout the gastro-entero-pancreatic tract, anterior pituitary, thyroid and all adrenomedullary cells. However, mid- to C-terminal antisera immunostained a subpopulation of chromogranin A positive cells. Most notable of these was with the KELTAE antiserum (R635.1) which immunostained discrete clusters of adrenomedullary cells and antiserum A87A which immunostained a subpopulation of cells in the anterior pituitary and throughout the gastrointestinal tract. The present study has demonstrated the widespread occurrence of chromogranin A and related peptides in rat neuroendocrine tissues and provides evidence of tissue and cell specific processing.

(1974). Archives of Disease in Childhood, 49, 796. Neonatal secretion of gastrin and glucagon. Plasma gastrin and glucagon levels were estimated in mothers after labour, and in their babies at birth and on the fourth day of life. The newly born baby appears to secrete gastrin independently and the plasma levels are higher on the fourth day of life. The cord gastrin level is lower when labour is induced or augmented by the intravenous infusion of oxytocin. Our results do not exlude the possibility that gastrin is transferred from mother to baby during a spontaneous labour. Such a maternal component of cord gastrin may be responsible for neonatal gastric hyperacidity.The mean cord glucagon level is higher than the maternal level at birth and the fourth day level is higher than the cord level. The C-terminal reactive glucagon-like inmmunoreactivity (C-GLI) in the cord blood is lower when oxytocin has been used during labour. Maternal or placental transfer of C-GLI during labour to the spontaneously born baby is one possible explanation of this finding.The raised glucagon levels on the fourth day may explain why there is low gastric acidity at this time despite the gastrin level being higher than at birth. No relation could be deduced between the C-GLI, i.e. pancreatic glucagon level, and the blood glucose level either at birth or on the fourth day of life.

-This study examined gastrointestinal hormone and peptide responses when glucose was ingested after prolonged exercise. Six endurance-trained male athletes ran on a treadmill for 2 h at 60% V O2 max. Immediately after the run, the athletes consumed 75 g of glucose in 250 ml of water (ExGLU) or flavored water as a placebo control (ExPL). On a separate visit, the athletes rested for 2 h and then consumed glucose (Con-GLU). During the first 60 min of recovery from exercise alone (ExPL), plasma vasoactive intestinal peptide (VIP), gastrin, and glucagon-like peptide-1 (GLP-1) all increased significantly, whereas glucose, insulin, and gastric inhibitory polypeptide (GIP) were unchanged from the immediate postexercise value. When glucose was ingested after exercise (ExGLU), glucose, insulin, VIP, gastrin, GLP-1, and GIP were all increased (P Ͻ 0.01). However, when glucose was ingested after resting for 2 h (ConGLU), VIP levels were unaffected, although glucose, insulin, gastrin, GLP-1, and GIP levels increased (P Ͻ 0.05). The plasma glucose response was greater (P Ͻ 0.03) and the plasma insulin response lower (P Ͻ 0.004) during ExGLU compared with ConGLU. There was a significantly higher (P Ͻ 0.01) VIP response during the initial period of recovery in ExGLU than there was with both ExPL and ConGLU. Plasma VIP showed a modest negative correlation with circulating glucose (r ϭ Ϫ0.35, P Ͻ 0.03) and insulin (r ϭ Ϫ0.37, P Ͻ 0.03) during the ExGLU recovery period. In summary, when glucose is ingested after prolonged exercise, there is mild insulin resistance and a corresponding rapid transitory increase in plasma VIP. These data suggest that VIP may play an important glucoregulatory role when glucose is ingested during the immediate postexercise recovery period. insulin resistance; gut peptides; exercise performance; carbohydrate THE IMMEDIATE POSTEXERCISE PERIOD appears to be associated with mild reversible insulin resistance, which is characterized by an attenuated insulin response and an increased glucose response to oral glucose (10,21,25,27,33,37,39,43). The physiological basis for the increased glucose response has been shown to be partly a function of greater release of glucose from the splanchnic tissues (20,30,39). Gut peptides and hormones of the enteroinsular axis may also play an important functional role in fuel homeostasis and contribute to maintaining a balance between energy utilization and mobilization. The metabolic role of peptides from the enteroinsular axis, including vasoactive intestinal peptide (VIP), gastric inhibitory polypeptide (GIP; also called glucose-dependent insulinotropic polypeptide), and glucagon-like peptide-1 (GLP-1), are known. However, the response of these peptides during recovery from exercise and the role they may play after glucose ingestion in the immediate postexercise period is less clear.VIP is secreted by the central (CNS) and peripheral (including enteric) nervous systems in response to duodenal acidification, gastric distention, and meal consumption (6, 40). Its actions incl...