Potassim-aldosterone-renin interrelationships.

The present study was performed to assess the sensitivity of the renin-angiotensin-aldosterone axis to small changes in plasma potassium concentration within the physiologic range. Small increments in potassium levels were accomplished by graded constant infusions of potassium chloride over 2 h (0.17 meq/min; 0.33 meq/min; 0.5 meq/min) in 8 normal subjects on a 10 meq sodium-100 mgq potassium intake. Plasma levels of aldosterone, renin activity, angiotensin II, cortisol, potassium and sodium were measured at frequent intervals. There were no significant changes observed in plasma sodium, renin activity or angiotensin II levels while cortisol levels declined in the expected diurnal pattern. During the 0.17 meq/min (10 meq/h) infusion potassium levels did not increase significantly until 120 min while plasma aldosterone levels rose significantly at 30-60 min. The mean increment above control during the lowest infusion rate was 0.2 meq/liter (5%) for plasma potassium and 13 ng/100 ml (46%) for plasma aldostreone. Although there was a stepwise increase in the increments above control of both potassium and aldosterone levels as the rate of the infusion was increased, the most sensitive area of the dose response curve appears to be 0.1-0.5 meq/liter. in six normal subjects the potassium-lowering effect of glucose ingestion (0.25 g/kg/15 min over a 2-h period) was assessed. The mean maximal potassium decrement below control 0.3 meq/liter (8%) at 90 min was coincident with the mean plasma aldosterone decrement below control of 11 ng/100 ml (46%). Plasma aldosterone then rose to peak levels at 180 min (mean increment 22 ng/100 ml above nadir) while potassium levels remained below control. The rise in plasma aldosterone was associated with a parallel but more rapid rise in plasma renin activity, peaking at a level 108% above control. Ninety minutes after the termination of the glucose ingestion, plasma aldosterone returned to control levels but now in the setting of reduced levels of plasma potassium and elevated levels of plasma renin activity. The data support an important role for physiologic changes in extracellular potassium concentration in the control of aldosterone secretion and indicate that interpretation of studies assessing acute changes in plasma aldosterone must carefully consider minor simultaneous changes in plasma potassium levels. The data also document that acute changes in extracellular potassium concentration play a role in the regulation of renin secretion.

Adrenocortical response to marathon running.

Plasma cortisol and plasma aldosterone levels were measured before and immediately upon completion of a marathon run in 7 highly conditioned male subjects in order to evaluate the response of the adrenal cortex to physical exertion. Both cortisol and aldosterone values rose significantly in response to the stress of the muscular exertion of the 26 mile, 385 yard run.

Salient clinical features of Sheehan's syndrome.

The natural history of Sheehan's syndrome is chronic. There is a long delay between peripartum hemorrhage and diagnosis. The majority of patients delivered at home and resided in rural areas where modern obstetric care was not readily attainable. The syndrome should be suspected in patients who present with asthenia-weakness, adrenal crisis and secondary amenorrhea. The symptoms that the patients usually had were secondary amenorrhea, asthenia-weakness, loss of axillary and pubic hair and failure to lactate. The important physical signs were loss of pubic and axillary hair, dry skin, slow relaxation phase of deep tendon reflex, hypopigmented areolar and pallor. The common laboratory features of the patients were anemia, eosinophilia, hypoalbuminemia, elevation of serum SGOT but not SGPT, hyponatremia and low fasting plasma glucose.

Glimepiride in type 2 diabetes mellitus Thai patients.

This study aimed to confirm the efficacy of glimepiride given once daily in the treatment of Thai type 2 diabetic patients and to find out the optimum dosage for Thai patients. The patients were enrolled at the diabetic clinics of 5 hospitals (Rajavithi, Chulalongkorn, Pramongkutklao, Siriraj and Theptarin Hospitals). All patients started glimepiride 1 mg once daily and escalated to 2, 3, 4 and until 6 mg every 4 weeks if fasting plasma glucose (FPG) exceeded 140 mg/dL. Subjects were 60 females and 29 males with an average age of 52.2 +/- 10.0 years. Mean BMI was 25.5 +/- 3.8 kg/m2. Fifty seven patients (64.0%) were drug naïve and thirty two patients (36.0%) had been previously treated with oral hypoglycemic agents. Seventy three per cent of the drug naïve and 37 per cent of the previously treated patients could be controlled with 1-2 mg of glimepiride once daily. At the twelfth week of treatment, mean fasting plasma glucose decreased from 224.6 to 156.6 mg/dL (30% reduction) and mean HbA1c decreased from 10.0 to 7.5 per cent (25% reduction). At the end of the study 49.4 per cent of the patients had HbA1c < 7.0 per cent, 21.3 per cent had HbA1c 7.0-8.0 per cent and 29.3 per cent had HbA1c > 8.0 per cent. Adverse events that were probably or possibly related to the drug were reported in 5 patients (5.6%). Three of them were hypoglycemia and two patients had skin rash. All hypoglycemic episodes were mild. Glimepiride was indicated to be safe. There were no clinically significant changes in clinical laboratory values, physical examinations and vital signs. In conclusion, glimepiride was efficacious and safe in type 2 diabetes Thai patients and 1-2 mg of glimepiride appeared to be a sufficient dose for most newly diagnosed type 2 diabetic patients.

Impediment of the progressions of microalbuminuria and hyperlipidemia in normotensive type 2 diabetes by low-dose ramipril.

In a randomized, double-blind, placebo-controlled study, we investigated in normotensive type 2 diabetics with microalbuminuria the effect of ramipril, an ACE inhibitor, on urine albumin excretion and serum lipids. A total of 1,882 patients were screened for urine microalbumin consecutively by dipstick test, Rapi Tex-Albumin test and RIA. The final 28 normotensive and microalbuminuric patients were assigned to receive either ramipril (1.25 mg/d, n = 16) or placebo (n = 12) for 12 weeks. Throughout the study, both groups had no changes in blood pressure, fasting plasma glucose, HbA1C, serum creatinine and electrolytes and no difference in creatinine clearance. At week 12 only the placebo group showed the significant increment of urine albumin excretion and triacylglycerol (30.6 +/- 38.3 to 39.0 +/- 19.7 and 167 +/- 64 to 208 +/- 77 mg/dl, respectively) but the decrement of HDL-cholesterol (46 +/- 16 to 35 +/- 6 mg/dl). During a 3 month period, increased urine albumin excretion was observed in normotensive type 2 diabetes with microalbuminuria who received only placebo. We conclude that ramipril may arrest the progression of albumin excretion and had favorable effects on serum lipids. Ramipril was safe and well-tolerated without untoward side effects during the study period.