Different imaging modalities may be of use in unclarified disease states. Positron emission tomography (PET) with F-18fluorodeoxyglucose (F-18-FDG) depicts cellular glucose metabolism with a high uptake being indicative of a high cellular turnover and, hence, consistent with ongoing infection, inflammation, or high grade malignancy (Hess, et al., 2014). Functional imaging with somatostatin anal...

The vasoactive intestinal peptide (VIP) and somatostatin (somatotropin release inhibiting factor, SRIF) are important neurotransmitters in a number of basic physiological events. Their disturbances have been reported in many diseases such as cystic fibrosis, impotent man (VIP), Alzheimer's disease, and some tumours (SRIF). Xestospongine B (1), sceptrine (2), and ageliferine (3), three alkaloids...

Several analogs of somatostatin with conformational constraints in their peptide backbones have been modeled to determine energetically feasible conformations. Comparison of low-energy backbone structures of these peptides suggested unique conformations of the central Phe/Ala(i)-D-Trp(i+1)-Lys(i+2)-Thr(i+3) fragment characteristic for specific interactions of somatostatin with each of the five ...

The neuropeptide somatostatin inhibits hormone release from GH4C1 pituitary cells via two mechanisms: inhibition of stimulated adenylate cyclase and a cAMP-independent process. To determine whether both mechanisms involve the guanyl nucleotide-binding protein Ni, we used pertussis toxin, which ADP-ribosylates Ni and thereby blocks its function. Pertussis toxin treatment of GH4C1 cells blocked s...

conclusions cyclosom and histamine synergistically exert catalepsy in old rats. in light of these data, the combination of the decreased brain level of somatostatin and increased brain level of histamine may be of pathogenic relevance for extrapyramidal signs in pd. results cyclosom (0.2, 1.0, and 5.0 µg) and histamine (1.0 and 10.0 µg) alone were ineffective in both young and old animals. in c...

The ligands interacting with enterochromaffin-like (ECL) and parietal cells and the signaling interactions between these cells were investigated in rabbit gastric glands using confocal microscopy. Intracellular calcium concentration ([Ca(2+)](i)) changes were used to monitor cellular responses. Histamine and carbachol increased [Ca(2+)](i) in parietal cells. Gastrin (1 nM) increased [Ca(2+)](i)...

The newly developed multireceptor somatostatin analogs pasireotide (SOM230), octreotide and somatoprim (DG3173) have primarily been characterized according to their binding profiles. However, their ability to activate individual somatostatin receptor subtypes (sst) has not been directly assessed so far. Here, we transplanted the carboxyl-terminal phosphorylation motif of the sst(2) receptor to ...

Somatostatin is a tetradecapeptide with potent inhibitory actions on several endocrine systems; it blocks the release of growth hormone, follicle stimulating hormone and thyrotropin from the pituitary gland (Krulich et al., 1968; Brazeau et al., 1973; Hall et al., 1978; Reichlin, 1983) and several peptide hormones from the endocrine gut and pancreas (Cohen et al., 1978; Gerich, 1981). It also a...

Somatostatin-receptor 1 (sst1) is an autoreceptor in the central nervous system that regulates the release of somatostatin. Sst1 is present intracellularly and at the cell surface. To investigate sst1 trafficking, rat sst1 tagged with epitope was expressed in rat insulinoma cells 1046-38 (RIN-1046-38) and tracked by antibody labeling. Confocal microscopic analysis revealed colocalization of int...