Acute Effects of Short-term Fasting on Blood Pressure,Circulating Noradrenaline and Efferent Sympathetic Nerve Activity

ABSTRACT Eleven moderately obese women, aged 46–62 years, with a body mass index of 29–34 and with borderline hypertension (repeated diastolic blood pressure >90 mmHg) fasted for 48 hours. Before the fast and after 48 hours of fasting, plasma noradrenaline, urinary noradrenaline, urine potassium, urine sodium and weight were measured. In six of the patients muscle nerve sympathetic activity was recorded from the peroneal nerve by tungsten micro-electrodes for 15 min each time. The efferent muscle sympathetic activity (MSA) was expressed as the number of bursts/min. The recordings were done before the fast and after 48 hours of fasting. We found significant decreases in body weight from 88.4±2.5 kg to 86.4±2.5 kg. Systolic blood pressure (BP) was reduced from 158±3 mmHg to 146±5 mmHg (p<0.001) and diastolic BP from 96±3 mmHg to 89±3 mmHg (p<0.01) during the fast. MSA was significantly increased from 42.0±5.5 bursts/min to 44.5±5.8 (n=6), while plasma and urine noradrenaline concentrations (n = 11) showed a non-significant tendency to increase. We conclude that the hypotensive response during the first days of extensive caloric reduction is not due to a decreased sympathetic activity. If anything, there may be weak increase of efferent sympathetic nerve activity and venous plasma levels of circulating noradrenaline. The mechanisms behind the acute hypotensive response to negative caloric balance are thus still unclear, but obviously different from long-term adaptation of the blood pressure.     

Long-term Results in 64 Patients Operated Upon for Pheochromocytoma

During the years 1956–1982, 64 pheochromocytoma patients were operated upon without mortality. Twenty-eight patients had sustained hypertension and 29 paroxysmal hypertension only. In two patients high blood pressure was not related to pheochromocytoma and five subjects were normotensive. In two women the pheochromocytoma demonstrated malignancy by widespread metastases. Sixteen patients also had neuroectodermal manifestations other than pheochromocytoma. Preoperatively, heart disease was found in most of the hypertensive patients aged 50 years or more at operation, but was uncommon in the others. In these subjects, heart disease persisted after surgery. Young subjects with sustained hypertension were not less affected by preoperative cerebrovascular accidents than older subjects. After surgery, hypertension persisted in 12 patients, and was easily controlled by drug therapy in eight. Nine patients died 7 months-18 years after surgery. In no case was the death directly associated with the pheochromocytoma disease. Three died from other neuroectodermal abnormalities. The 55 surviving patients have been followed up for a mean of 12 years after surgery. During the observation time the survival of the pheochromocytoma patients was similar to that of the normal population. At the end of the study, 44 out of the 55 surviving patients were free from symptoms.     

Streptococcus mutans in plaque and saliva after mouthrinsing with SnF2

Abstract – Mouthrinses with SnF2 in 11 subjects significantly reduced ( P <0.01) the total colony forming units (CFU) count and the numbers of Streptococcus mutans and Streptococcus sanguis in plaque. The numbers of S. mutans and S. sanguis were significantly more reduced than was the total CFU count. After rinsing with SnF2 S. sanguis was present in 97% and S. mutans in only 42% of plaque samples from tooth surfaces where they were detected after rinsing with water. SnF2 also significantly reduced ( P <0.01) the number of S. mutans in saliva. Mouthrinses with NaF did not markedly affect the number of S. mutans either in plaque or in saliva.     

Testicular blood flow measured with a laser Doppler flowmeter: acute effects of catecholamines

Laser Doppler flowmetry was used to continuously measure testicular blood flow in rats. The method was found applicable on surgically exposed testes. Regular oscillations in blood flow, with a periodicity of 8.6±0.7 cycles per minute (mean ± SD), were observed in recordings from 22 of 23 rats. Clamping of the testicular artery reduced the blood flow signal to background values. Effects of catecholamines administered into the tail artery on testicular blood flow together with systemic effects on mean arterial blood pressure and heart rate were measured. It was found that noradrenaline as well as adrenaline caused a significant decrease in blood flow when 10 μg was injected. Only noradrenaline decreased the blood flow when 1 μg was given. The large oscillations detected in the blood flow recordings disappeared quickly when 10 or 1 μg of both hormones was administered. It was concluded that catecholamines can exert rapid effects on testicular blood flow.     

Rejection of an HL—A Identical Renal Transplant

A 38-year-old man suffering from chronic glomerulonephritis received a kidney from his HL—A identical sister. The HL—A identity was fully established by tissue typing with well-specified antisera and by mixed lymphocyte culture tests. One year after transplantation kidney function deteriorated, and repeated biopsies of the transplant, I¹³¹-Hippuran renography, and arteriography showed that the kidney was undergoing a chronic rejection. It is suggested that incompatibilities with regard to weak histocompatibility systems might have been responsible for the rejection of a human kidney.     

Successful Pediatric Stenting of a Nonthrombotic Coronary Occlusion as a Complication of Radiofrequency Catheter Ablation

This is a case of a right coronary artery occlusion complicating a RF catheter ablation of a posteroseptal accessory connection in an 8-year-old boy. After multiple balloon angioplasty attempts in the occluded vessel, only transient patency was achieved. The occlusion was successfully treated with placement of an intracoronary stent.     

ETHANOL AND PHOSPHATIDYLETHANOL REDUCE THE BINDING OF [3H]INOSITOL 1,4,5-TRISPHOSPHATE TO RAT CEREBELLAR MEMBRANES

In this study, we have analysed the effect of ethanol and phosphatidylethanol,a unique phospholipid formed only in the presence of ethanol,on the binding of [³H]inositol 1,4,5-trisphosphate to rat cerebellarmembranes. Rats were intraperitoneally injected daily with 3g of ethanol/kg body weight for different periods of time. Repeatedadministration of ethanol induced a reduction in the bindingcapacity (B_max) without affecting the affinity constant (K_d).A significant 32% reduction was observed after 21 days of exposure(from control B_max values of 25±3 pmol/mg and K_d valuesof 9±2 nM). In an in-vitro assay, phosphatidylethanol(500 µM) and phosphatidic acid (500 µM), but noother phospholipids tested, induced a reduction in B_max (39%and 43%, respectively). The observed effect displayed by phosphatidylethanolwas not due to its degradation to phosphatidic acid or otherphospholipids. The results emphasize the importance of examiningphosphatidylethanol (PEth) as a possible mediator of the effectsof ethanol on cellular processes. However, the role of PEthin the observed effect of long-term ethanol exposure still needsfurther consideration.