Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Information on adverse health effects of occupational exposures to sodium sulfate dust is lacking. A study was conducted on 119 workers from five sodium sulfate surface solution mines in Saskatchewan. The investigation involved the older workers and the workers at highest dust exposure levels and included general medical screening with emphasis on the existence of hypertension, edema, calcium tetany, anemia, common skin problems, nasal septum perforation, persistent diarrhea; lung function tests; serum analyses for sulfate, calcium, sodium, and chloride content; and urinary inorganic sulfate output. All measured properties, including lung function, serum sulfate, calcium and electrolytes, were found to be within normal ranges. Forty-two workers with more than 10 years exposure experience show no significant differences in these properties compared to 77 workers with less than 10 years exposure experience. No abnormality could be discovered that might be related to such exposure.
 ...
PMID:Health effects of long-term exposure to sodium sulfate dust. 73 42

The presence of three pools of exchangeable calcium (A,B and C) was demonstrated by the method of investigating the kinetics of 45Ca efflux from the fat issue of rats; the two most slowly exchangeable pools (B and C) reflected the distribution of intracellular calcium. The calcium content in the pools B and C of the fat tissue of rats with spontaneous hypertension was increased by 71 and 29%, respectively, as compared to that in the normotensive controls. Adrenalectomy leads to a marked redistribution of intracellular calcium, but the differences between spontaneously hypertensive rats and normotensive rats in the calcium content in the pools B and C are nonetheless maintained. These differences in the distribution of intracellular calcium may be the direct cause of the change in the hormonal sensitivity of the adipocytes of rats with spontaneous genetic hypertension.
 ...
PMID:[Disturbance of the intracellular calcium distribution in the fatty tissue of rats with spontaneous genetic hypertension]. 73 88

Spontaneously hypertensive rats (SHR) treated in utero with a low dose, and from weaning with 6 mg/kg per day of oral timolol, a noncardioselective beta-adrenergic blocker, did not develop hypertension. Isolated aortic rings from these animals showed increased reactivity to raised extracellular K+, when compared with tissues from timolol-treated Kyoto-Wistar (WKY) control rats. The normotensive SHR aorta also showed significant responsiveness to H+ and to high Ca2+ concentrations without previously depolarizing the tissue with high K+. These observations suggest that the increased reactivity seen in vascular smooth muscle from this animal does not develop secondary to elevated peripheral resistance and subsequent hypertrophy, and that the initiation of hypertension in this animal may be related to a membrane defect and (or) cellular defect which results in a facilitation of Ca2+ availability for the contractile proteins of the SHR vascular smooth muscle cell.
 ...
PMID:Elevated vascular reactivity in the timolol-treated spontaneously hypertensive rat. 74 25

In isolated bath studies smooth muscle from the rat portal vein was evaluated for its reactivity and contractility, and the whole vessel wall was evaluated for its extensibility. Smooth muscle from the spontaneously hypertensive rat (SHR) had the following characteristics when compared with that from normotensive controls: (1) Spontaneous phasic contractions were more frequent and developed more tension; (2) threshold concentrations for responses to prostaglandins A-2 and B-2 were lower, but those for responses to epinephrine, norepinephrine, KCl, BaCl-2, and SrCl-2 were similar; (3) high concentrations of calcium had a less depressant action on the responses to the prostaglandins but not on the responses to the other agonists; (4) maximal contractile tensions to all agonists were greater; and (5) passive extensibility was less. These differences, because they are in the venous system, cannot be secondary to the increase in wall stress of arterial hypertension. The decreased passive extensibility in this vein in SHR creates a stiffer framework on which the active contractile process is able to develop greater tension. If this increase in active tension is generalized to all veins, it could be responsible for a decrease in venous capacity which increases the rate of venous return and, hence, increases cardiac output.
 ...
PMID:Venous smooth muscle in hypertension. Enhanced contractility of portal veins from spontaneously hypertensive rats. 80 71

Elderly participants in Title VII congregate feeding programs in Indianapolis can be characterized generally as being retired, usually living alone, and often reporting some disease condition, particularly arthritis, hypertension, and/or heart disease. On an average weekday, the nutrient intake of these people, except for zinc, approximated the amounts suggested in the Recommended Dietary Allowances. Fifty-nine per cent of the subjects consumed less than two-thirds of the allowance for zinc. Generally, they consumed over half of their allowances for eight nutrients at the site meal. The nutritional significance of apparent low intakes of dietary zinc among subjects is not clear. Eleven per cent had hair zinc levels below 100 mcg. per gram, but none were below 70 mcg. Therefore, on the basis of hair zinc levels, none could be absolutely calssified as zinc deficient. Although hair zinc levels were not correlated to dietary zinc intake, they were inversely correlated to dietary calcium and fat intake. Taste acuity by these elderly participants was generally less than that reported for young adults. However, women had greater taste acuity for sodium chloride than men. Sixteen per cent of the subjects were particularly insensitive to the taste of sodium chloride. Finally, there was no correlation between taste acuity and dietary zinc intake.
 ...
PMID:Zinc nutriture of elderly participants in an urban feeding program. 83 Jul 6

The effect of Sr++, Ba++ and Mn++ on calcium uptake by a plasma membrane-enriched fraction from mesenteric arteries of spontaneously hypertensive rats (SHR) was studied to determine what alterations in divalent cation interactions are associated with hypertension. 45Ca++ uptake in the presence of ATP by this fraction from SHR was significantly greater than that of normotensive rats (NWR). This 45Ca++ uptake by these fractions from both types of rat could be reduced by Ba++, Sr++ and nonradioactive Ca++, but not by Mn++; the ability of these cations to compete with 45Ca++ was in the following order Ca++ greater than Sr++ greater than Ba++. In contrast, 45Ca++ uptake in the absence of ATP by this subcellular fraction from SHR was significantly less than that of NWR, and this passive 45Ca++ binding could be displaced by Mn++ in addition to the other cations. Both qualitative and quantitative differences were found between SHR and NWR in this study of the effects of cations on calcium uptake by arterial plasma membrane. These results suggest that the plasma membrane of SHR arteries has calcium-binding and transport properties that are different from those of NWR. However, there is not a complete correlation between the reported effects of the cations on contraction of other arteries in hypertension and on calcium uptake by membranes of SHR and NWR.
 ...
PMID:Alterations in calcium transport and binding by the plasma membrane of mesenteric arteries from spontaneously hypertensive rats. 83 62

Sodium and calcium contents of cardiovascular tissue in spontaneously hypertensive rats (SHR) and DOCA hypertensive rats were investigated. The effect of salt loading on these contents of SHR and control Wistar rats was also investigated. Calcium content increased with the development of hypertension, but not sodium content particularly in salt loading rats and at the sustained stage of DOCA hypertensive rats. These results suggest that calcium rather than sodium is more intimately related to the increase in blood pressure.
 ...
PMID:Studies on sodium and calcium contents of cardiovascular tissue in experimental hypertension. 83 30

An 8-year-old boy presented at UCLA Hospital with a one month history of hypertension prior to suffering a sudden onset of acute abdominal pain, rectal bleeding, peritonitis, and shock. Sigmoidoscopy showed diffuse mucosal friability. At laparotomy, inflammation and edema of the entire colon and terminal ileum were detected with two necrotic areas on the cecum. A 5 cm right adrenal pheochromocytoma with a hemorrhagic center was removed and a diverting loop ileostomy with inversion of the necrotic cecal areas was performed. Postoperatively, the blood pressure gradually returned to normal, and the colitis improved. Serum calcium and T3 T4 levels were normal. Review of the literature demonstrates that in patients with pheochromocytoma, progression from colitis to necrosis can be precipitated by a hypotensive episode. This patient suggests an example of catecholamine induced enterocolitis.
 ...
PMID:Enterocolitis with peritonitis in a child with pheochromocytoma. 84 39

In three hypertensive uremic children in whom hypertension was not controlled by sodium-free diet, ultrafiltration and hypotensive drugs, a total of twenty low sodium concentration hemodialyses were carried out. In all patients there was insignificant sodium excretion in urine and diastolic blood pressure diminished 10 to 20 mm Hg; two patients showed also reduction of systolic blood pressure. No important changes were seen in the serum concentrations of sodium, calcium and glucose. In one patient improvement of his retin lesions, as well as radiological reduction of heart size were observed. In other two cases, cardio-respiratory symptoms associated with hypertension disappeared. In all but two of them hypotensive drugs were withdrawn; in the other one dose was reduced. With low sodium concentration hemodialysis, sodium extraction was higher than that obtained when using the conventional dialysis solution. Interchangeable sodium decreased in all patients.
 ...
PMID:[Hemodialysis with low sodium concentration in hypertensive uremic children]. 84 94

Properties of the longitudinal smooth muscle of portal veins from normotensive Wistar rats, adult (NCR) and young (NCRy); spontaneously hypertensive Okamoto rats, adult (SHR) and young (SHRy); and adult Wistar rats with renal hypertension (RHR) were studied in vitro and histologically. Some aortic strips from SHR and SHRy were compared with controls. In response to noradrenaline (NA) and acetylcholine (ACh) greater maximum force was developed by veins from all hypertensive groups than by those from control rats. Cross-sectional area of the longitudinal muscle of veins from SHR but nor SHRy nor RHR was greater than control. Maximum stress in response to agonists was greater in both SHR and RHR than NCR. ED50-values for NA and ACh were lower in portal veins from SHR than NCR but not from RHR nor SHRy compared to controls. Denervation did not abolish any of the differences between SHR and NCR. Aortic strips from SHR developed less maximum force to NA and ED50 was greater than those from NCR, i.e. opposite to the findings in portal veins. Low levels of external Ca2+ reveal altered calcium handling in veins from SHR compared to controls. It is concluded that portal veins from hypertensive rats are functionally different from those of normotensive rats and differ in SHR compared to RHR. It is suggested that the altered functional properties of portal vein, but not of aorta, in several respects resemble those of arterial resistance vessels. The implications of these findings are discussed in terms of mechanisms of hypertension in these animal models.
 ...
PMID:Contractility, muscle mass and agonist sensitivity of isolated portal veins from normo- and hypertensive rats. 85 13


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>