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Biomedical subjects

G Granerus

Publications and source records attributed to G Granerus.

At least 91 records · Page 5Linked to original sources
PubMed1980

Studies on histamine metabolism in allergen-induced asthma.

The excretion of histamine (Hi) and it metabolite methyhistamine (MeHi) was determined in separated fractions of urine up to 12h after standardized allergen provocations in 18 adult patients with defined extrinsic bronchial asthma. The main histamine metabolite, methylimidazoleacetic acid (MeImAA), was measured in six of the patients. After positive provocations (decrease in FEV1 greater than 20%) the excretion of Hi was significantly increased during 3h and that of MeHi during 4h after challenge. Negative provocations (decrease in FEV1 less than 20%) were not followed by any changes in the excretion of Hi and MeHi. MeImAA excretion increased in five out of six patients after positive provocation. It was calculated that the increased excretion of Hi and its metabolites after a positive provocation corresponded to a release of about 1 mg histamine in the body or about 1 microgram/g lung tissue if all histamine was liberated in the lung. Pretreatment with two anti-allergic drugs, disodium cromoglycate and ICI 74.917, giving significant allergen protection, resulted in a smaller increase of the excretion of both Hi and MeHi, indicating an inhibition of histamine release in vivo.

Adolescent↗
PubMed1980

Effect of cimetidine treatment on parietal and chief cell sensitivity to histamine and on catabolism of histamine in duodenal ulcer patients.

Gastric acid and pepsin output in response to a low and a maximal dose of histamine was studied before and 60 h after cessation of 4 weeks of cimetidine treatment, 1 g/day, in 11 duodenal ulcer patients. Plasma histamine concentrations were measured in eight patients and the urinary excretion of intravenously injected 14C-histamine and its metabolites in two patients. Acid and pepsin output in response to the low dose of histamine as a percentage of the maximal response was on average 41.3% +/- 4.4% (S.E.M.) and 46.3% +/- 3.5% before treatment and 40.4% +/- 4.8% and 38.8% +/- 4.5% after cessation of treatment, respectively (p greater than 0.10). Thus, a course of treatment with cimetidine does not influence the sensitivity of the parietal and chief cells to histamine stimulation in duodenal ulcer patients. No significant change of plasma histamine concentrations and of catabolism of radiolabelled histamine was observed after cessation of cimetidine treatment.

Adult↗
PubMed1980

Methodological aspects of renography in children.

Kidney function in children by renography has been evaluated. For reproducible results a high degree of standardization with respect to position, hydration and dosage was necessary. The wide range of kidney size and depth in children requires age-adapted collimators. For practical use for different size have been constructed for the age-groups: less 1 year, 1-5 years, 6-9 years and 10-15 years. A reduction in the surrounding activity of the kidneys is thereby obtained and disturbing influence from the bladder or contralateral kidney is prevented. Kidney function variables from the renogram are presented in terms of uptake and excretion ratios. The correlation between sum of uptake ratios and clearance measurements is good in cases with slight or moderate difference in kidney size. The standardized renographic technique has many advantages for kidney function measurements in children. The method is applicable in all ages, it is simple and reliable without extensive preparations and requires a low radiation dose. Also in children we can confirm the previous opinion obtained in adults that renography is a clinical valuable method of measuring kidney function.

Adolescent↗
PubMed1980

A simple method of background subtraction in two-detector renography.

To increase the accuracy in the routine measurement of the side distribution of kidney function from 131I-Hippuran renograms, a simple method of background subtraction has been developed. Principally a background curve was adapted to the renogram on each side, assuming an initial amplitude corresponding to the amplitude of phase I of the renogram. The amplitudes of the renogram over background after 2 min is recognized as a measured of kidney function and a background quotient was calculated by dividing the background curve amplitude at 2 min with its initial amplitude. Mean values of the background quotient recorder over thorax was 0.62 and over an empty kidney region 0.73. It was found that a quotient of 0.70 could be used generally, thus omitting the need for a background curve registration at each renographic examination.

Adolescent↗
PubMed1980

Evaluation of unilateral kidney function in children. A comparison between renography and separate clearance.

Unilateral kidney function in children was evaluated by determination of 51Cr-EDTA-clearance combined with estimation of side distribution of kidney function by renography. As reference, separate clearance of 51Cr-EDTA, determined by sequential external ureteral occlusions on both sides, was used. A comparison between these two methods was made in 28 patients with varying degrees of unilateral kidney function impairment. A significant correlation was found when the renograms were corrected for extrarenal background activity. Thus, renography in combination with determination of the glomerular filtration rate with 51Cr-EDTA is a valuable method for evaluating separate kidney function in children, both methods being easily performed and requiring small radiation doses.

Adolescent↗
PubMed1980

Kidney split function in children. A comparative study between renography and planimetry from urography.

The suitability of the background-subtracted renogram as a method for separate kidney function in children was evaluated by comparison with planimetry of the individual renal parenchymal area measured from urography. In different groups of renal disorders the total kidney function as reflected by the glomerular filtration rate has been compared with the sum of right and left renal parenchymal areas. The percentage side distribution of kidney function estimated from the renogram combined with measurements of total glomerular filtration rate has been correlated to individual renal parenchymal area. A good correlation was found for both total and separate measurements. A moderate scatter around the regression lines has to be taken into consideration when kidney function is judged from planimetry. A highly significant correlation was observed between renography and planimetry for the percentage distribution of kidney function, indicating that both methods are well suited for determining the side distribution of kidney function. For calculation of individual kidney function, combination of renography and 51Cr-EDTA-clearance offers a reliable method with a modest dose of irradiation.

Adolescent↗
PubMed1980

Gastric acid secretion (GAS) and hiatal hernia. I. Relationship between GAS and oesophageal reflux complications.

The relationship between GAS and oesophageal reflux complications in patients with hiatal hernia and incompetent antireflux mechanism is a matter of controversy. In a study of 70 patients operated upon for hiatal hernia, BAO and PAO after betazole stimulation were studied preoperatively in relation to oesophageal reflux complications, age and oesophageal motility. No correlation was found between BAO and oesophageal reflux complications. There was no association between PAO and such complications in patients with oesophageal hypomotility whereas PAO was clearly correlated to these complications in patients with normal oesophageal motility. Oesophageal reflux complications were closely correlated to oesophageal hypomotility and age.

Adult↗
PubMed1980

Gastric acid secretion (GAS) and hiatal hernia. II. Relationship between GAS and clinical results after hernia repair.

The indications for surgical procedures reducing gastric acid secretion in patients with hiatal hernia and symptomatic gastroesophageal reflux remain unclear. In a study of the postoperative results in 40 patients operated upon with modified Husfeldt hernia repair only, the results were assessed in relation to BAO and PAO. No correlation was found between the clinical results and BAO or PAO in patients in whom the reflux was successfully corrected by the procedure. It is concluded that gastric acid-reducing procedures are not indicated in patients in whom correction of reflux is anticipated.

Esophagus↗
PubMed1979

Studies on histamine metabolism in intrinsic bronchial asthma.

Histamine metabolism was investigated in patients with intrinsic asthma, during the acute phase and in remission, by determination of the urinary excretion of histamine metabolites. During acute attacks the excretion of methylhistamine (MeHi) and 1-methyl-4-imidazoleacetic acid (MeImAA) was significantly increased compared with healthy subjects. The excretion of MeHi was significantly increased during acute attacks compared with remission. The excretion of MeImAA was also increased, but the difference was not significant. The correlation between the excretion of MeHi and MeImAA was highly significant. Corticosteroids, given to some patients during remission, did not affect the excretion of histamine and its metabolites. Smoking and respiratory infection during the acute attacks were both accompanied by increased excretion of MeHi. The results indicate that there is an increased histamine turnover in acute attacks of intrinsic bronchial asthma.

Acute Disease↗
PubMed1979

Cyclic AMP, renal function and dihydralazine-stimulated renin secretion in hypertensive patients.

The concentrations of plasma cAMP and plasma renin activity were determined in arterial and renal venous plasma in nineteen patients investigated for renin-mediated hypertension. The cAMP measurements were performed in two different situations (1) under basal conditions and (2) after i.v. dihydralazine administration, a potent renin stimulation procedure. Thirteen patients had a lateralization of the renin secretion in the basal state and the administration of dihydralazine caused a further marked renin-secretion. The cAMP concentration was higher in the renal veins draining renin-positive kidneys than in the contralateral renal veins. No significant change was observed between the arterial cAMP concentration and the cAMP concentration in either of the renal veins during dihydralazine-stimulated renin secretion. There was no correlation between the cAMP extraction and the renin secretion of the individual kidneys, but the cAMP extraction correlated with the extraction ratio of PAH. These results show that cAMP values are mainly influenced by the renal function and are not related to the state of renin secretion. Increased cAMP levels in renovascular patients and urameic patients are therefore mainly due to defective elimination of the nucleotide by the kidneys.

Aged↗
PubMed1979

Histamine metabolism in severe obesity before and after jejuno-ileostomy.

Histamine metabolism was studied in three patients during histamine-reduced diet before and at intervals after jejuno-ileostomy by analyses of the urinary excretion of non-labelled and 14C-labelled histamine and its metabolites. Labelled histamine was administered intravenously and orally. The preoperative excretion of free histamine and its endogenously formed metabolites was essentially the same as in controls. After intestinal bypass the inactivation of [14C]histamine by both routes of administration was not impaired. Pronounced increases in the excretion of non-labelled conjugated histamine (acetylhistamine) and methylimidazoleacetic acid were found at different intervals postoperatively. This was probably due to histamine synthesis by intestinal bacteria since the diet only contained minute quantities of histamine. It is concluded that the increased urinary excretion of conjugated histamine after intestinal bypass indicated an abnormal bacterial activity in the intestine.

Adult↗
PubMed1979

Increased urine histamine after challenge of contact sensitivity in the mouse.

The urinary excretion of histamine was observed daily during the development of contact sensitivity to picryl chloride in the mouse. After challenge, effected by painting the ears, urine histamine increased about four fold, while the histamine content in the ears did not change significantly. It is suggested that during challenge there is a general release of histamine, which may be the result either of an immediate hypersensitivity reaction or an effect of anaphylatoxin formation after complement activation.

Administration, Topical↗
PubMed1978

Observations on the use and limitations of renal vein renins in hypertensive patients.

From our consecutive series of renal vein renin studies in 170 patients with kidney disorders and hypertension, we present those cured by surgical correction of a unilateral renal artery stenosis during the period 1973--75. The renin secretion patterns of these patients range between no demonstrable abnormality, even with a stimulating procedure using dihydralazine 7.5 i.v., and massive renin secretion already during basal conditions. Thus, the renin secretion may not be increased even after stimulation in some patients with durable unilateral renovascular hypertension. This fact may be explained by the rise of the systemic blood pressure, eventually maintained by sodium and water retention and accompanied by adaptive changes in the contralateral kidney. The perfusion pressure is thereby kept normal in the affected kidney, eliminating a stimulus for renin secretion. It is likely that many cases of renovascular hypertension pass through an early stage where no involvement of the renin-angiotensin system may be discovered. Of course, these patients will also benefit from surgery. The conclusion is that renin studies for diagnostic purposes should be performed when patients are on treatment and kept normotensive for some time, and that an additional challenge of the perfusion pressure, i.e., by use of dihydralazine, intravenously should be performed.

Humans↗
PubMed1977

Renin-dependent hypertension in patients with unilateral kidney disease not caused by renal artery stenosis.

The practical value of renin secretion studies in hypertension associated with unilateral kidney disease, other than renal artery stenosis, has not been documented. This study, comprising 19 patients of this kind, disclosed three who had an abnormal renin secretion from the diseased kidney. The level of peripheral renin under basal conditions, and the change from this level as a result of provocation of renin secretion, were used to evaluate the importance of an arteriovenous renin gradient in the diseased kidney. The three patients were the only ones to become normotensive when the diseased kidney was removed in seven of the cases studied. When nephrectomy is considered in severe hypertension with unilateral kidney disease, there is a place for renin secretion studies, but a screening procedure is advisable. Measuring peripheral renin under basal conditions and after provocation of renin secretion, should reveal whether the renin-angiotensin system might be playing a part in maintaining the high BP. The finding of diminishing kidney function in many of the patients, despite good BP control, emphasizes the importance of sparing kidney function whenever possible.

Adolescent↗
PubMed1977

Histamine metabolism in normal pregnancy and in toxaemia of pregnancy.

The urinary excretion of histamine and its metabolites, methylhistamine, methylimidazoleacetic acid and imidazoleacetic acid, was measured under standardized dietary conditions in 24 women with normal pregnancies and in eleven patients with toxaemia of pregnancy. In addition, histamine metabolism was studied in five healthy women at delivery and in four other healthy pregnant women during treatment with aminoguanidine, which is an inhibitor of diamino oxidase (histaminase). A slight increase in the urinary excretion of methylimidazoleacetic acid was observed in normal pregnancy as well as in toxaemia of pregnancy compared to non-pregnant women. In two toxaemic patients and in one of the healthy subjects the urinary excretion of unmetabolized histamine was moderately increased. Despite the very high diamino oxidase activity in the plasma and in the uterus during pregnancy, there were no signs of altered catabolism of endogenous histamine in the pregnant women. Smoking increased the urinary excretion of the quantitatively dominant histamine metabolite, methylimidazolacetic acid, in pregnant subjects as it also does in nonpregnant subjects. The necessity of standardized dietary conditions in the study of histamine metabolism in man was again emphasized.

Adult↗
PubMed1976

Histamine metabolism of the guinea-pig gastric mucosa.

1. The mobilization of gastric mucosal histamine as reflected by changes in formation and content has been studied in guinea-pigs on feeding and after injections of pentagastrin or 2-deoxy-D-glucose. 2. Re-feeding fasting guinea-pigs as well as injections of pentagastrin or 2-deoxy-D-glucose raised the rate of mucosal histamine formation; pentagastrin induced a fourfold rise. 3. Some properties of the enzyme catalysing the formation of histamine were examined. The results indicated that this enzyme is histidine decarboxylase, L-histidine carboxy-lyase, E.C. 4.1.1. 22. 4. The enzyme imidazole-N-methyl transferase, E.C. 2.1.1.8, which carries out methylation of the imidazole ring to yield 1-methyl-4-(beta-aminoethyl)imidazole (methylhistamine), was found in high amounts in the mucosa. The enzyme did not change upon stimulation of the mucosa. 5. The metabolism of histamine within the gastric mucosa is discussed in relationship to a suggested role of the amine in exciting acid secretion.

Animals↗
PubMed1976

Histamine metabolism during the menstrual cycle.

The urinary excretion of histamine and its metabolites methylhistamine (MeHi) and methylimidazoleacetic acid (MeImAA) was measured during the menstrual cycle in nine healthy women, one allergic woman and three non-pregnant women with anovulatory regular cycles. Simultaneous urinary analyses of luteinizing hormone (LH) and total estrogens were performed. The healthy women showed individual variations in the excretion of histamine, MeHi and MeImAA. This observation has been interpreted as an expression of minor individual differences in the catabolism of histamine. At midcycle an increase in the urinary excretion of histamine metabolites was sometimes evident and a statistically significant correlation could be established between MeHi and estrogen in urine. These results may support previous findings of histamine release by estrogens in uterine tissue but may also reflect an elevated histamine formation. The allergic woman excreted constantly increased amounts of histamine and its metabolites, especially when her allergic symptoms became aggravated pre-menstrually. She did not exhibit any change in MeImAA excretion at midcycle but the MeHi-excretion varied with the excretion of estrogens in the urine. The subjects with anovulatory menstrual cycles had low values of histamine and metabolites although within the normal variations.

Anovulation↗