Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0403608 (ureter)
 9,655 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Prostaglandin E2 (PGE2) and 16,16-dimethyl PGE2 (16,16-dm PGE2) caused contraction of guinea-pig taenia caeci, contraction and at higher concentrations relaxation of trachea and relaxation of ureter smooth muscle. The prostacyclin derivative iloprost induced contraction of taenia caecum, while it was inactive in the other preparations. After pretreatment of the smooth muscles with 16,16-dm PGE2, stimulation of the PGE2 receptors in taenia caeci and trachea and of PGI2 receptors in taenia caeci caused relaxation. The results indicate that the prostanoid receptor mediating contraction is selectively vulnerable for desensitization in contrast with the receptor mediating smooth muscle relaxation.
 ...
PMID:Desensitization of PGE2 and PGI2 induced contractions in different smooth muscles of guinea-pig unmasking relaxing properties of prostanoids. 245 36

Exposure to whole body radiation is associated with prompt changes in urinary excretion of prostaglandins. We investigated the separate effects of radiation on rat kidney capillary and tubular system prostaglandin synthesis. Animals were irradiated to the left kidney area with a single dose of 15 Gy. One week later the rats were anesthesized, the renal artery, vein and ureter of the left kidney cannulated, and the kidney removed and perfused with Krebs-Henseleit physiological buffer at a rate of 10-12 ml/min. Effluent fluids were collected separately from the renal vein and from the ureter of irradiated and control (operated sham-irradiated animals) and were assayed by radioimmunoassays for thromboxane A2 (TXB2) and prostacyclin (6 keto PGF1 alpha). Histological examination of the irradiated kidneys showed no significant changes, and electron microscopy revealed minimal interstitial edema. In contrast to these minimal changes, TXB2 assays showed a significant increase both in the venous and ureter effluents. Following stimulation with angiotensin II in the perfusate, a further significant increase in TXB2 production was observed both by the capillary and the tubular systems. With 6 Keto PGF1 a slightly different response was seen. The basal production was increased only in the ureter effluent of the irradiated animals, while there were no changes in the release in the venous effluents. In parallel, radiation significantly increased the angiotensin II stimulated production capacity of prostacyclin by the tubular system. The response of the capillary system following irradiation may create imbalance between these two important substances and lead to the radiation effects in the renal tissue.
 ...
PMID:The effects of ionizing irradiation on production of thromboxane and prostacyclin by the isolated perfused rat kidney. 297 45

In the present study, metabolism of prostaglandins (PGs) by 15-hydroxyprostaglandin dehydrogenase (15-OH PGDH) was investigated in dog kidneys with ureteral obstruction. After 24 hr of ureteral obstruction, the obstructed kidney and the contralateral kidney were removed and the cytosolic fractions (105,000 X g), enriched in 15-OH PGDH, were prepared from the cortex and medulla. 15-OH PGDH activity was estimated by radiometric assays of the metabolism of [3H]PGE2 and [3H]prostacyclin. Cortical 15-OH PGDH activity decreased by greater than 50% in the ureter-obstructed kidney as compared to the contralateral kidney. Similar results were obtained by estimating the stereo-specific release of tritium from position 15 using 15-[3H]PGF2 alpha as substrate. In contrast to the cortex, there were no differences in 15-OH PGDH activity found in the medulla of the obstructed and contralateral kidneys. Because the cortex contains higher levels of 15-OH PGDH activity, the deficiency in that site may contribute to the elevated levels of PGs in renal venous blood during ureteral obstruction.
 ...
PMID:Deficiency in 15-hydroxyprostaglandin dehydrogenase activity after unilateral ureteral obstruction of the dog kidney. 388 82

The prostaglandins (PGs) synthesized from C14-arachidonic acid by the homogenized sheep ureter were identified as being prostacyclin (PGI2), PGF2 alpha and thromboxane B2 (TXB2). The radioimmunoassay (RIA) estimation of 6-keto-PGF1 alpha, a stable metabolite of PGI2, confirms that it was the major metabolite of arachidonic acid. Aqueous extracts of fresh garlic (5, 12.5, 25 and 50 mg/ml) were shown to inhibit the synthesis of the prostanoids in a dose dependent manner. Fresh garlic extracts (1, 2.5, 5 and 10 mg/ml) also dose dependently inhibited spontaneous rhythmic contractions of the isolated ureter. Boiled garlic (5, 12.5, 25 and 50 mg/ml) had no effect on either ureteral motility or the PG synthesizing capacity of the sheep ureter.
 ...
PMID:Aqueous extracts of garlic (Allium sativum) inhibit prostaglandin synthesis in the ovine ureter. 830 20

The purpose of this study was to investigate the site of production (urothelium/smooth muscle) and quantitative release of prostanoids in the ureter. Quantitative analysis of prostacyclin (PGI2) was by its metabolite, 6-keto PGFalpha, thromboxane (TXB2) and prostaglandin F2alpha. Synthesis by radiometry and radioimmunoassay was performed in vitro in sheep ureter specimens before and after removal of the inner epithelial layer and after addition of indomethacin. The major prostanoids present in the ureter were PGI2 and TXB2; PGI2 was quantitatively the largest component. Removal of the thin inner epithelial layer (urothelium) reduced mostly PGI2; addition of arachidonic acid significantly augmented PGI2 only in ureters with intact urothelium but did not alter TXB2 levels. The main source of prostanoid synthesis (PGI2) of the ureter is to be found in the urothelium. The functional role of the prostanoids may be related to coordination of peristalsis.
 ...
PMID:Urothelial synthesis of prostanoids in the ovine ureter. 969 98