Adrenocorticoid regulation of Na+,K(+)-ATPase in adult rat kidney: effects on post-translational processing and mRNA abundance.

The mechanisms by which adreno-corticoid hormones regulate Na+,K(+)-ATPase in adult kidney were studied in adrenalectomized (Adx) rats. Five days after adrenalectomy, Na+,K(+)-ATPase activity was significantly reduced in the renal cortex homogenate (C = 13.0 +/- 0.8 vs. Adx = 7.1 +/- 0.7 mumol Pi mg-1 protein h-1) and in renal microsomes (C = 30.3 +/- 1.9 vs Adx = 14.6 +/- 1.3 mumol Pi mg-1 protein h-1). Glucocorticoid replacement treatment of adrenalectomized rats with betamethasone (20 micrograms kg-1 body wt twice daily for 5 days) effectively counteracted the observed reduction in Na+,K(+)-ATPase activity. In cortical homogenate the protein level of alpha 1 and beta 1 subunits measured in immunoblots was not significantly different in Adx and control rats, indicating that 5 days after adrenalectomy the alpha 1 and beta 1 subunits were present in renal cortical cells to almost normal extent but could not be assembled into a transmembrane functional unit. In support of this conclusion we found that the protein level of both the alpha 1 and beta 1 subunits was significantly lower (P less than 0.001 for both subunits) in microsomes from Adx than in control rats. The mRNA abundance for alpha 1 and beta 1 subunits were not lower in Adx as compared to control rats 1 and 5 days after surgery. However, if Adx rats were given a single dose of betamethasone (600 micrograms kg-1 body wt), a significant 2-fold increase in both alpha 1 and beta 1 mRNAs was observed (P less than 0.05 for both subunits).(ABSTRACT TRUNCATED AT 250 WORDS)     

Use of autologous fibrin glue in the treatment of splenic trauma: an experimental study.

There is little doubt that preserving the spleen will contribute to a much more favourable outcome in patients undergoing splenic surgery, as a result of avoiding the well known risks of splenectomy. Among many operative methods described for splenic salvage, application of autologous fibrin glue (AFG) is particularly promising because of its unique characteristics. The use of AFG has been evaluated and its efficacy and tissue compatibility assessed in the treatment of splenic trauma in 15 partially splenectomized New Zealand White rabbits. The application of the AFG to the resected splenic surface achieved complete haemostasis in all animals. The animals were divided into four groups and were killed at varying intervals ranging from 24 h to 10 weeks. During re-exploration there was no evidence of recurrent bleeding and histopathological examination revealed progressive absorption of the AFG with a minimal inflammatory response. It is concluded that AFG is an effective haemostatic agent with good systemic and local compatibility and can be used in splenic salvage, which thereby avoids the use of non-autologous products with their risks of disease transmission.     

Status of the renin-angiotensin-aldosterone system in patients with a neuroendocrine-metabolic type of the hypothalamic syndrome]

The paper is concerned with the results of a radioimmunoassay of the state of the renin-angiotensin-aldosterone system in patients with a neuroendocrine-metabolic type of the hypothalamic syndrome. They received pathogenetic therapy with peritol (an antiserotonin drug) or parlodel (a dopaminergic drug) during three months and routine therapy. The latter was not enough to return to normal the basal blood levels of aldosterone, reaction of the glomerular zone of the adrenocortical substance and the juxtaglomerular apparatus of the kidneys. Peritol therapy normalized the blood concentration of aldosterone; reactions of the glomerular zone of the adrenocortical substance and the juxtaglomerular apparatus to insulin hypoglycemia and furosemide acute testing improved considerably. After a course of parlodel therapy blood concentration of aldosterone got to normal, and reaction of the glomerular zone of the adrenocortical substance and the juxtaglomerular apparatus to insulin hypoglycemia was unchanged whereas it improved after furosemide testing.     

Organizational principles of mass screening and therapeutic tactics in arterial/occlusive diseases of the lower extremities

Determination of the ankle-shoulder index (ASI) was used in addition to clinical examination for the detection and monitoring of patients with obliterating arterial lesions of the legs. In individuals with suspected obliterating lesions, the ASI served as a criterion for the identification of normal, affected and high-risk groups and determined the strategy and duration of treatment and the follow-up schedule. ASI variation following surgery on arteries of the legs was an objective indicator of the efficiency of the operation and furnished indications for repeated surgical intervention to prevent reocclusion.     

Histamine inhibits 5-hydroxytryptamine release from the porcine small intestine: involvement of H3 receptors.

Strips of the porcine small intestine were incubated in vitro, and the release of 5-hydroxytryptamine (5-HT) was determined by high-pressure liquid chromatography with electrochemical detection. Removal of the mucosa resulted in a large reduction (95%) of tissue 5-HT, suggesting that enterochromaffin cells are the main source of 5-HT. The release of 5-HT was reduced by 70% after omission of calcium. Tetrodotoxin and hexamethonium reduced the release of 5-HT by 30%-40% in a nonadditive manner, indicating a spontaneous neuronal (nicotinic) excitatory input to the enterochromaffin cells. Histamine inhibited the release of 5-HT by about 50%. This effect was not affected by mepyramine or cimetidine but was effectively blocked by thioperamide, indicating the involvement of H3 receptors. The selective H3-receptor agonist R-alpha-methyl-histamine also inhibited 5-HT release. Because the effect of R-alpha-methyl-histamine was also observed in the presence of tetrodotoxin, an indirect, neuronally mediated action could be excluded. Therefore, the inhibitory H3 receptors may be localized directly at the enterochromaffin cells.     

Spatial learning impairments in rats with selective immunolesion of the forebrain cholinergic system.

A monoclonal antibody to the low-affinity NGF receptor, 192 IgG, coupled to a cytotoxin, saporin, was recently introduced as an efficient selective neurotoxin for the NGFr-bearing cholinergic neurones in the rat basal forebrain. In the present study we report that an intracerebroventricular injection of this 192 IgG-saporin conjugate induces a severe, long-lasting spatial learning impairment, as assessed in the Morris water-maze task. This behavioural impairment was associated with 65-90% depletion of choline acetyltransferase activity (ChAT) in the hippocampus and cortex. ChAT activity associated with other cholinergic neurone systems in the brain (striatum, mesencephalon, spinal cord), was left virtually unaffected. This new immunotoxin holds great promise as a tool for selective and efficient lesions of the forebrain cholinergic system in functional and behavioural studies.     

Action profiles of smoking and caffeine: Stroop effect, EEG, and peripheral physiology.

Twenty female regular cigarette smokers and coffee drinkers performed a numerical Stroop task in a 2 x 2 (caffeine x smoking) prepost crossover design. In the easier of the two different versions, caffeine and smoking reduced the reaction times (RT's) when given alone, but there was no additive effect. The Stroop effect itself (difference between RT's to numbers and RT's to symbols) was reduced by the two treatments only in the more difficult version, but the combination did not differ from the placebo condition. The physiological reactions to both treatments were additive, although the two reaction profiles were different. Smoking increased heart rate, blood pressure, finger vasoconstriction, respiratory frequency, EEG dominant alpha-frequency, and beta power and reduced respiratory amplitude, EEG delta and theta power. Caffeine increased blood pressure, finger vasoconstriction, motor activity, frontal EMG, and EEG theta power and decreased heart rate and EEG beta power.