Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UNIPROT:P61278 (
somatostatin
)
22,083
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Idiopathic orthostatic hypotension (IOH) represents a degenerative disorder of the peripheral nervous system characterized by low values of arterial blood pressure during orthostatism, with reduction in serum catecholamines. Since treatment of symptomatic IOH has been unsatisfactory till now, we studied the hemodynamic response to
somatostatin
(S) (Octreotide, 100 micrograms sc) at rest (R) and during sympathetic activation (tilting, T) by means of 2D and/or color Doppler echocardiography, in 5 ambulatory IOH patients (4M, 1F; aged 65 +/- 5 years), with simultaneous recording of blood pressure and heart rate. Post-S, an increased blood pressure was evident during T without heart rate modifications (pre- vs post-S, SAP: 92 +/- 9 vs 148 +/- 12;
DAP
: 61 +/- 4 vs 90 +/- 9 mmHg; p less than 0.05), while systolic echo parameters did not change significantly. Doppler aortic velocity curve showed during T a reduction of Vmax (pre- vs post-S: 0.98 +/- 0.09 vs 0.73 +/- 0.03 m/s; p less than 0.05) and of cardiac output, due to unchanged preload. Pre-S, at rest, Doppler mitral velocity curve presented a normal E/A ratio as in normal subjects, with a reduced E peak and an increased A peak post-S, indirect signs of increased afterload. Pre-S, E and A peak velocities underwent progressive decrease during T, markedly more evident post-S. Total peripheral resistance, at rest and during T, increased post-S too (pre- vs post-S, rest: 2406 +/- 267 vs 3162 +/- 599; T: 1634 +/- 201 vs 2784 +/- 425 dyne*s/cm-5; p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:[Hemodynamic response to somatostatin at rest and during sympathetic activation in idiopathic orthostatic hypotension]. 191 13
Intracerebroventricular
somatostatin
administration to conscious rats results in a characteristic motor abnormality (barrel rotation), convulsions that are frequently fatal and destruction of cerebellar Purkinje cells. This study demonstrates that each of these manifestations of this neuropeptide can be attenuated by pretreatment with diazepam (
Valium
, 5 mg/kg, i.p.) but not in vehicle-pretreated controls. Specifically, the incidence of mortality was reduced from 5/12 controls to 2/20 diazepam-treated rats, the incidence of barrel rotation was reduced from 6/12 controls to 2/20 diazepam-treated rats and the incidence of Purkinje cell death was reduced from 4/4 examined controls to 4/13 diazepam-treated animals. Vehicle pretreated rats did not differ from untreated rats. Thus, in addition to blocking
somatostatin
-induced motor dysfunction and mortality, diazepam offers significant protection from central neuronal cell death in the cerebellar cortex.
...
PMID:Diazepam attenuation of somatostatin-induced motor disturbances and neurotoxicity. 290 96
The effects of the benzodiazepines and
somatostatin
(SS) on learning and memory are the opposite of each other. To investigate a possible relationship between these two components, the effects of the administration over time of diazepam and of a benzodiazepine antagonist, 2-phenylpyrazolo [3,4-c]-quinolin-3(5H)-one (CGS 8216), on the levels of
somatostatin
-like immunoreactivity (SSLI) and on the binding of [125I]Tyr11-
somatostatin
were studied in the hippocampus of the Wistar rat.
Diazepam
(5 mg/kg/day, i.p.) and CGS 8216 (20 mg/kg/day, i.p.) did not affect SSLI in the hippocampus, at the three times studied (3, 7 or 14 days). Administration of diazepam for 3 or 7 days decreased the number of
somatostatin
receptors in synaptosomes from the hippocampus, without influencing their apparent affinity. This decrease could be blocked by concomitant administration of CGS 8216, whereas CGS 8216 alone had no observable effect. After 2 weeks of daily injections of diazepam the levels of binding of
somatostatin
in the hippocampus returned to control values, coinciding with the tolerance that develops to chronically-administered benzodiazepine agonists. These results suggest that
somatostatin
receptors might be regulated by benzodiazepine receptors and perhaps may also play a role in some of the behavioural effects of the benzodiazepines.
...
PMID:The effect of diazepam and the benzodiazepine antagonist CGS 8216 on the somatostatinergic neuronal system. 809 64
Diazepam
binding inhibitor (DBI1-86) has recently been isolated in search for a cholecystokinin (CCK)-releasing peptide in the duodenum that is responsible for the feedback regulation of exocrine pancreatic secretion. Synthetic porcine DBI1-86 stimulates CCK release in vivo and in vitro from isolated intestinal mucosal cells. We postulated that DBI intraduodenally releases CCK in a paracrine fashion and might be the missing link in the feedback regulation of exocrine pancreatic secretion.
Somatostatin
, peptide YY (PYY) and taurocholate are known to inhibit feedback-stimulated CCK release in the rat. In this study, we investigated the effect of
somatostatin
, PYY and taurocholate on DBI-stimulated CCK secretion. Dispersed rat intestinal mucosal cells were prepared from the proximal small bowel and continuously perfused. The perfusate was collected and the release of CCK into the medium was measured. DBI1-86 dose-dependently stimulated CCK release, with a maximal effect at 10(-9) M.
Somatostatin
blocked the DBI-stimulated CCK release. Pretreatment of the cells with pertussis toxin fully reversed the inhibitory effect of
somatostatin
on DBI-stimulated CCK secretion, suggesting that
somatostatin
exerts its action by an inhibitory G-protein. In contrast, PYY (10(-6) M) and taurocholate (10(-6) M) did not affect DBI stimulated CCK levels, indicating that they act through different mechanisms to inhibit feedback-stimulated CCK release.
...
PMID:Regulation of the action of the novel cholecystokinin-releasing peptide diazepam binding inhibitor by inhibitory hormones and taurocholate. 971 81
Numerous reports in both humans and animals have confirmed that benzodiazepines produce amnesia; however, mechanisms mediating this effect are not clear. In view of the important role of brain
somatostatin
(SRIF) in the cognitive function of rats, this study sought to determine if the benzodiazepine, diazepam, alters somatostatinergic system in the rat frontoparietal cortex. Intraperitoneal (i.p.) administration of diazepam (5 mg/kg/day) to male Wistar rats (200-250 g) for 3 or 7 days decreased the number of SRIF receptors (26 and 37%, respectively) in synaptosomes from the frontoparietal cortex, without influencing their apparent affinity. This decrease in the tracer binding was not attributable to a direct effect of diazepam on SRIF receptors, because no decrease of SRIF binding was induced by a large concentration of diazepam (10(-4) M) when the drug was added to a preparation of synaptosomes from frontoparietal cortex of untreated rats. To determine if the effect of diazepam on SRIF binding is related to the binding of diazepam to its recognition site on the GABA(A) receptor, a benzodiazepine antagonist, 2-phenylpyrazolo[3,4-c]quinolin-3(5H)-one (CGS 8216) was administered before the diazepam injection. Pretreatment with CGS 8216 (20 mg/kg/day, i.p.) blocked completely the diazepam-induced decrease in the number of SRIF receptors. CGS 8216 alone had no observable effect. The decrease in the number of 125I-Tyr11-SRIF receptor induced by diazepam was accompanied by a decrease in the effect of SRIF, after 15 seconds of stimulation, on inositol 1,4, 5-trisphosphate (IP3) mass accumulation in the rat frontoparietal cortex at 3 (64%) or 7 days (59%) after its administration.
Diazepam
alone had no observable effect on mass accumulation of IP3. After 14 days of daily diazepam injections, the levels of binding of 125I-Tyr11-SRIF in the frontoparietal cortex returned to control values, coinciding with the tolerance that develops to this benzodiazepine agonists when administered chronically. The decrease in IP3 levels was still observed after 14 days (57%) diazepam administration.
Diazepam
and CGS 8216 did not affect SRIF-like immunoreactivity levels in the frontoparietal cortex at the three time intervals studied (3, 7 or 14 days). The alteration of frontoparietal cortex SRIF receptor-effector system after 3 or 7 days of diazepam treatment suggests that somatostatinergic neurotransmission plays a role in the mechanism of diazepam action on memory.
...
PMID:Diazepam attenuation of somatostatin binding and effect of somatostatin on accumulation of inositol 1,4,5-trisphosphate in the rat frontoparietal cortex. 1088 44
Diazepam
suppressed arginine-induced glucagon release from the isolated perfused rat pancreas in a dose-dependent manner, with an IC50 of approximately 65 microM. In contrast, insulin release was enhanced by 10-50 microM diazepam, but inhibited by higher concentrations of drug. Thus, 50 microM diazepam simultaneously suppressed glucagon and increased insulin release in this model. The potentiation of insulin release may result from phosphodiesterase inhibition. The inhibitory effects on hormone release are discussed in terms of diazepam's molecular conformation, which is similar to that of diphenylhydantoin, an inhibitor of both glucagon and insulin release in the isolated perfused rat pancreas. The possibility is also considered that the conformation of both compounds might be similar to the apparent active site of the hormone release inhibitor
somatostatin
.
...
PMID:Diazepam: in vitro effects on glucagon and insulin release. 1562 63