Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0011849 (diabetes)
 277,896 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

All of the components of the neuropeptide vasoactive intestinal peptide (VIP) signal transduction system were underexpressed in rat prostatic membranes 6 weeks after streptozotocin-induced diabetes. Binding studies with [125I]VIP showed decreases of 86% and 62% in the binding capacity of the high and low affinity classes of VIP receptors in diabetes. Affinity labeling experiments indicated that the main form of VIP receptor was 51 kilodaltons in control rats and 45 kilodaltons in diabetic animals. The efficacy of VIP and forskolin in stimulation of adenylyl cyclase activity as well as the potentiating effect of GTP on VIP action were also reduced in diabetes, as was the expression of the alpha-subunit of the guanine nucleotide-binding regulatory proteins Gs and Gi (studied by ADP ribosylation with cholera and pertussis toxins). Gi function was lost in diabetes, as assessed with experiments on guanyl-5'-yl-imidodiphosphate potentiation of forskolin activity. These disturbances together with previous findings argue for VIP playing a role in the diabetic neuropathy of the genitourinary tract.
 ...
PMID:The effect of streptozotocin diabetes on the vasoactive intestinal peptide receptor/effector system in membranes from rat ventral prostate. 132 26

The urinary bladder and urethral content of substance P and vasoactive intestinal polypeptide and the in vitro effects of the peptides on the bladder were studied at 6 weeks and 6 months of streptozotocin-induced diabetes in the rat. The results were compared with those obtained in age-matched control animals. Both short-term and long-term streptozotocin treatment induced a clearcut increase in bladder weight. Bladder substance P content was increased in both groups of diabetic animals but substance P concentration was similar in control and diabetic animals. Vasoactive intestinal polypeptide content was slightly higher in diabetic animals than in controls but vasoactive intestinal polypeptide concentration was significantly lower in the bladders from both short-term and long-term diabetic animals. The bladder contractile response to substance P was similar in all groups of animals and vasoactive intestinal polypeptide was found to be devoid of contractile or relaxatory effects in the rat bladder. No change in urethral weight was seen with diabetes. There were no clear-cut changes in the urethral contents or concentrations of substance P and vasoactive intestinal polypeptide. The study also enabled comparisons between younger (3 months) and older (9 months) rats. This comparison showed a decrease in the concentrations and contents of substance P and vasoactive intestinal polypeptide between young and older rats. The changes were seen in both the bladder and the urethra and were similar in diabetic and normal animals.
 ...
PMID:Effects of age and streptozotocin-induced diabetes on contents and effects of substance P and vasoactive intestinal polypeptide in the lower urinary tract of the rat. 137 98

Neuropeptides in perivascular nerves of vasa nervorum supplying blood to rat optic, sciatic, vagus and sympathetic chain nerve trunks are differentially vulnerable to streptozotocin (STZ)-induced diabetes. Immunohistochemical analysis of epineurial/perineurial nerve sheaths showed that 8 weeks after induction of diabetes, the density of neuropeptide Y (NPY)-immunoreactive nerve fibres in optic nerve sheaths was increased, while it was decreased in sciatic, vagus and sympathetic nerve sheaths. Vasoactive intestinal polypeptide (VIP)-immunoreactivity was increased in vasa and nervi nervorum of optic, sciatic, vagus and sympathetic chain nerve sheaths. Immunoassay of NPY confirmed increased levels in optic nerve sheaths and showed that substance P and calcitonin gene-related peptide levels increased in sciatic but not optic nerve sheaths. Neuropeptide levels in the intrafascicular nerve fibres were unaffected. This provides further evidence for a disturbance in the autonomic control of blood flow to peripheral and cranial nerve trunks via vasa nervorum in STZ-induced diabetes, which may lead to ischaemic changes, alter local axon reflexes and contribute to the pathogenesis of the disease.
 ...
PMID:Differential vulnerability of neuropeptides in nerves of the vasa nervorum to streptozotocin-induced diabetes. 163 9

The distribution of vasoactive intestinal polypeptide (VIP) and substance P-like immunoreactivities was studied by immunohistochemistry in the myenteric plexus and circular muscle layer of the ileum and proximal colon of rats 8 wk after induction of diabetes with streptozotocin. A consistent increase was observed in fluorescence intensity of VIP-like immunoreactivity in the nerve fibers, and intensely stained cell bodies were significantly more frequent in the myenteric plexus of the ileum (p less than 0.001) from diabetic animals. Some varicosities of VIP-like immunoreactive fibers in the myenteric plexus appeared to be enlarged. Vasoactive intestinal polypeptide-like immunoreactivity was increased and VIP-like immunoreactive nerves appeared thicker in the circular muscle layer of both diabetic ileum and proximal colon. The VIP levels were measured biochemically in tissue consisting of the smooth muscle layers and myenteric plexus. A significant increase in the VIP content per centimeter of intestine was found in both the ileum (p less than and proximal colon (p less than 0.01) from diabetic rats. In contrast, no apparent change in substance P innervation was observed immunohistochemically in the myenteric plexus and circular muscle layer of either diabetic ileum or proximal colon when compared with controls. The results are discussed in relation to the symptoms of autonomic neuropathy of the gut in diabetes.
 ...
PMID:Enteric nerves in diabetic rats: increase in vasoactive intestinal polypeptide but not substance P. 241 33

Penile tissue (consisting of corpus cavernosum and tunica albuginea) was obtained from 19 patients undergoing surgery for the implantation of penile prostheses. The tissue was examined for vasoactive intestinal polypeptide-like immunoreactivity in nerves, acetylcholinesterase-positive staining in nerves and noradrenaline content. Impotence was due to a variety of causes; 11 patients were classified as a 'non-neuropathic' group on the basis of their clinical history which included Peyronie's disease, vascular disease, hypertension and psychogenic impotence. Vasoactive intestinal polypeptide-like immunoreactive and acetylcholinesterase-positive nerves were present and the pattern and distribution were similar in each patient in this group. The noradrenaline content of the tunica albuginea was significantly lower than the corpus cavernosum (p less than 0.02), although there was a linear relationship between the noradrenaline contents of the two regions (r = 0.95, p less than 0.01). By comparison, a complete absence of vasoactive intestinal polypeptide-like immunoreactivity in nerves was observed in a patient with a cauda equina lesion. Five out of six diabetic patients studied revealed a marked reduction in vasoactive intestinal polypeptide-like immunoreactivity in nerves associated with the cavernous smooth muscle, while acetylcholinesterase-positive staining was reduced in three out of five diabetic patients studied. The noradrenaline content of the corpus cavernosum from diabetic patients was significantly lower (p less than 0.02) than that of the 'non-neuropathic' group. The noradrenaline content of the tunica albuginea, however, was similar in both groups. The results provide evidence that VIPergic, cholinergic and adrenergic nerves in the penis are affected in diabetes mellitus and thus may contribute to the development of impotence in diabetic patients.
 ...
PMID:Changes in the VIPergic, cholinergic and adrenergic innervation of human penile tissue in diabetic and non-diabetic impotent males. 243 29

We report a case of pancreatic tumour metastatic to the liver in a patient with insulin-treated diabetes, anaemia, cheilitis, necrolytic migratory erythema, hypokalemia and chronic watery diarrhea, a picture suggesting combined glucagonoma and VIPoma syndromes. Immunocytochemistry of a biopsied hepatic metastatic nodule revealed both glucagon and vasoactive intestinal peptide (VIP) positive cells. Increased plasma glucagon and VIP levels were detected (values of 900 pmol/l and 277 pmol/l respectively). This is the first reported case showing not only immunocytochemical, but also clinical evidence of the combined secretion of these hormones.
 ...
PMID:A combined glucagonoma and VIPoma syndrome. First pathologic and clinical report. 284 62

The autonomic innervation of the seminal vesicle from 8 and 16 week streptozotocin-induced diabetic rats and age-matched controls was studied by pharmacological, histochemical and immunohistochemical methods. Contractions in response to electrical field stimulation, which were abolished using prazosin (2 microM) or tetrodotoxin (one to 1.6 microM), and to noradrenaline were significantly increased in both eight and 16 week diabetic animals. The contractile response to acetylcholine was significantly increased in the 16 week diabetic rats only, when compared with controls. Although these responses were significantly increased, no difference was found in ED50 and EF50 values between control and diabetic rats. Vasoactive intestinal polypeptide (0.3 microM) had no effect on resting tension or nerve-mediated responses. In seminal vesicles from control animals, both vasoactive intestinal polypeptide-immunoreactive and acetylcholinesterase-containing nerves were localised around the folds of the columnar epithelium of secretory cells, in contrast to neuropeptide Y-immunoreactive and catecholamine-containing nerves which were found in the smooth muscle layers. In seminal vesicles from both eight and 16 week diabetic animals no difference was seen in distribution or density of acetylcholinesterase-containing nerves; there was an increase in density and fluorescence intensity of vasoactive intestinal polypeptide- and neuropeptide Y-immunoreactive nerves and a decrease in catecholamine-containing nerves compared with controls. The results are discussed in relation to autonomic neuropathy in diabetes.
 ...
PMID:The seminal vesicle in eight and 16 week streptozotocin-induced diabetic rats: adrenergic, cholinergic and peptidergic innervation. 366 88

Previous studies have demonstrated mostly inhibitory effects of elevated plasma glucose levels on gastric exo- and endocrine as well as motor functions. Because increased plasma glucose levels reduce vagal activity via the central nervous system, it remains unclear if glucose exerts a direct effect on gastric functions. Therefore, our study was designed to determine the effect of acute changes in glucose concentrations on the release of gastrin and bombesin-like immunoreactivity (BLI) from the isolated perfused rat stomach. Acute elevations of perfusate glucose from 100 to 200 mg/dl or from 100 to 300 mg/dl augmented BLI secretion significantly without affecting gastrin release. During an acute decrease from 200 to 30 mg/dl, the secretion of both peptides remained unchanged. When acetylcholine was administered to stimulate BLI and gastrin secretion, the elevation of perfusate glucose to 200 mg/dl and the decrease to 30 mg/dl attenuated BLI secretion, whereas gastrin secretion remained unchanged compared with the control experiments at 100 mg/dl glucose. On the other hand, the perfusion of vasoactive intestinal peptide (VIP) and Leu-enkephalin had no effect on BLI and gastrin secretion during 100 mg/dl glucose perfusion, but both peptides elicited a significant stimulatory effect on BLI secretion during a perfusate glucose concentration of 200 mg/dl without affecting gastrin secretion. In conclusion, our study demonstrates first that an acute increase of glucose augments basal BLI secretion. Second, cholinergically induced BLI secretion is attenuated by hypo- and hyperglycemia. Third, hyperglycemia augments BLI secretion in response to the neuropeptides VIP and Leu-enkephalin. Fourth, basal and stimulated gastrin secretion remains unchanged during acute alterations of perfusate glucose levels.(ABSTRACT TRUNCATED AT 250 WORDS)
Diabetes 1986 Jul
PMID:Modulatory glucose effect on bombesin-like immunoreactivity and gastrin secretion from isolated perfused rat stomach. 372 Oct 63

Vasoactive intestinal polypeptide (VIP) has been demonstrated by immunofluorescence histochemistry in nerves in human and rat penile tissue. A reduction in VIP-like immunoreactivity in nerves was revealed in tissue from streptozotocin-diabetic rats and a human diabetic with impotence. These results suggest that an impairment in the VIP-ergic innervation in penile tissue may be an important factor in the development of impotence in diabetes. They also support the view that the streptozotocin-treated rat is a useful experimental model for diabetic autonomic neuropathy.
Diabetes 1983 Nov
PMID:Vasoactive intestinal polypeptide-like immunoreactive nerves in diabetic penis. A comparison between streptozotocin-treated rats and man. 635 6

Morphological, ultrastructural, and immunocytochemical studies of nerves containing vasoactive intestinal peptide (VIP) are described in diabetic pancreas of rats after streptozotocin treatment. The observations covered 48 hours and 6 months following streptozotocin treatment. At the ultrastructural level, degenerative changes were already observed in axons of nerve ganglia in the pancreas 48 hours (early stage) after streptozotocin treatment. These changes were hardly detected at the light microscopic level and VIP-like immunoreactivities were seen in nerves and fibers in such pancreas. The nerve ganglia were almost absent in the diabetic pancreas 6 months after streptozotocin treatment (late stage). Associated with the absence of nerve ganglia, nerves and fibers containing VIP-like immunoreactivities were also absent at this late stage. The findings indicated that the changes in the diabetic pancreas were neuropathic caused by metabolic disturbance after long standing diabetes and resulting absence of VIP-like immunoreactive nerves occurred. It was suggested from the present study that the changes in nerve ganglia began as damage at the ultrastructural level due to acute toxicity of the chemical at an early stage and then developed destruction and absence at a late stage.
 ...
PMID:VIPergic innervation of diabetic pancreas in rats. 638 99


1 2 3 4 Next >>