Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
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Gene/Protein
Disease
Symptom
Drug
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Target Concepts:
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Query: UNIPROT:P61278 (
somatostatin
)
22,083
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Several reports have described decreased immunoreactive
somatostatin
levels in specific regions of post-mortem brain tissue from patients diagnosed with senile dementia of the Alzheimer type (SDAT). In an attempt to determine if the metabolism of
somatostatin
is also altered as a result of SDAT, we examined the regional metabolic half-life of somatostatin-28 (SS-28) and somatostatin-14 (SS-14). The activity of the following peptidases was also determined: neutral endopeptidase E.C. 3.4.24.11; metalloendopeptidase E.C. 3.4.24.15;
carboxypeptidase E
(E.C. 3.4.17.10); and trypsin-like serine protease. The metabolic half-life of SS-28 was significantly reduced in post-mortem Brodmann Area 22 of SDAT tissue. This decrease in SS-28 metabolic half-life was correlated with a significant increase in trypsin-like serine protease activity in the same SDAT brain region. The formation rate of SS-14 from SS-28 incubated with Brodmann Area 22 homogenates was also increased in SDAT tissues as compared to controls. A regional variation in neutral endopeptidase E.C. 3.4.24.11 was also noted in both controls and SDAT samples. Although postmortem intervals of samples varied significantly, no effect was seen on any biochemical parameter measured. Results from this study provide evidence that a correlation can be made between changes in metabolic half-life
somatostatin
and alterations in neuropeptidase activities due to SDAT. As these data show alterations in both proteolytic metabolism and peptidase activities, many other biologically active peptide substrates could also be affected in SDAT.
...
PMID:Metabolic half-life of somatostatin and peptidase activities are altered in Alzheimer's disease. 134 49
Developmental patterns for rat pancreatic opioid peptides and islet hormones were studied from gestational day 20 through adulthood. Fetal tissue was obtained as well as pancreas at birth (day 0), and postnatal days 3, 7, 14, and 21, and 7 weeks. The hormones measured included insulin, glucagon, and
somatostatin
. The opioids measured were beta-endorphin, Met- and Leu-enkephalins, and the high molecular weight enkephalin precursors. Pancreata were pooled as necessary and extracted (acid alcohol, or hot acetic acid), and opioids were further purified on reversed-phase C-18 (Sep-pak) cartridges. In all instances measurements were made by radioimmunoassays. Precursor peptides were first digested (with trypsin and carboxypeptidase B) prior to immunoassay. All opioids and hormones except the precursors for enkephalins showed a well-defined surge in pancreatic concentration during the first postnatal week. In contrast, the precursors had the highest concentration in the fetus, and by the seventh day of life had decreased by greater than 50%. This progressive decrease may represent maturation of the
enkephalin convertase
and trypsin-like enzymes in the islets. The opioid and hormonal surges that we have described are similar to the surge in islet concentration of thyroid-releasing hormone (TRH) previously described in neonatal rat islets. It is suggested that these postnatal alterations in opioid and hormone concentration relate to a specific function in the development of the endocrine pancreas.
...
PMID:Developmental patterns for pancreatic opioids in the rat. 253 May 76
Enkephalin convertase (
carboxypeptidase E
,H;
EC 3.4.17.10
) is a carboxypeptidase B-like enzyme which appears to be physiologically associated with the biosynthesis of the enkephalins and certain other peptides. We have localized
enkephalin convertase
in the brain and other tissues autoradiographically by labeling studies with [3H]guanidinoethylmercaptosuccinic acid ([3H]GEMSA). In the brain, [3H]GEMSA localizations parallel enkephalin distribution but with certain exceptions, suggesting a role in relation to other peptides. In the pancreas, [3H]GEMSA binding sites are localized to the islets suggesting an involvement in insulin, glucagon, or
somatostatin
formation. The selective concentration of [3H]GEMSA grains in cardiac atria suggests a link to atrial natriuretic factor.
...
PMID:Enkephalin convertase: characterization and localization using [3H]guanidinoethylmercaptosuccinic acid. 313 43
Processing of most gut hormones involves cleavage between dibasic amino acids followed by carboxypeptidase-catalyzed removal of the COOH-terminal basic residue, resulting in peptides with a COOH-terminal glycine. Such peptides may subsequently be converted to amidated peptides or can be directly secreted. It is believed that
carboxypeptidase E
(
CPE
) is involved in gut hormone processing but its presence in gut endocrine cells has never been studied. We have analyzed the distribution of
CPE
in the antropyloric mucosa of rat stomach and report that gastrin cells and progenitor gastrin-
somatostatin
(G/D) cells express
CPE
while mature
somatostatin
cells and the majority of serotonin cells fail to express
CPE
. These data indicate that immature G/D cells are able to process gastrin to glycine-extended forms and that
CPE
-mediated processing is not a characteristic of mature
somatostatin
and serotonin cells.
...
PMID:Carboxypeptidase E in rat antropyloric mucosa: distribution in progenitor and mature endocrine cell types. 1466 Nov 9