A method is described for the simultaneous determination of major glucocorticoids in bovine plasma, that is, Cortisol, Corticosterone and Cortisone, which includes separation by high-pressure liquid chromatography and measurement using a UV detector (254nm). Chromatography on the Zorbax CN column is carried out with the eluent system, that is, n-hexane/ethanol (=87/13 v/v).
First, Dexamethasone was selected as the best internal standard under the previously mentioned conditions. The calibration curves for the glucocorticoids were all clearly linear. The recoveries for each 5ng of added Cortisol, Corticosterone and Cortisone were 96.7 ± 3.2%, 100.4 ± 2.3% and 96.1 ± 2.2%, respectively. The reproducibility of Cortisol was good and its coefficient of variation of intraassay was small (2.7%), whereas such coefficient was not so in Corticosterone (7.7%) and Cortisone (7.3%). This appears to be due to low concentrations of Corticosterone and Cortisone in the plasma. Specificity of this method to each glucocorticoid was ascertained using plasma from adrenalectomized wethers. In addition, the correlation coefficient between measurements of Cortisol by radioimmunoassay and those by this method was 0.978.
In conclusion, the method described in this paper appears to be satisfactory for the simultaneous quantification of plasma glucocorticoids.

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The evaluation of computed tomography (CT) for detecting aldosterone-producing adenoma in primary aldosteronism was performed by comparison with adrenal scintiscan; determination of aldosterone in adrenal or renal veins, retroperitoneal pneumography and adrenal venography was reliable for diagnosis of adrenal tumors in pheochromocytoma or Cushing's syndrome, but not so effective for small adenoma of primary aldosteronism.
An abdominal CT scan was performed on six patients with primary aldosteronism, one with idiopathic hyperaldosteronism and one with glucocorticoid responsive hyperaldosteronism; in an attempt to evaluate the utility of this noninvasive procedure. Diagnosis of hyperaldosteronism was made by demonstrating the elevated plasma aldosterone concentration and aldosterone secretion rate, normal excretion rate of urinary 17-OHCS and 17-KS, and low plasma renin activity.
The CT scan correctly predicted unilateral adrenal adenoma in all the patients with primary aldosteronism of which the findings were identical to those demonstrated by surgery. The diameter of these tumors ranged from 10 × 7 × 6 to 19 × 17 × 14mm. Also the CT scan in idiopathic hyperaldosteronism and glucocorticoid responsive hyperaldosteronism showed bilateral adrenal hyperplasia and bilateral normal adrenal glands, respectively. The pathological findings in these two cases disclosed the adrenal hyperplasia of zona glomerulosa and adrenal hyperplasia of zona subglomerulosa accompanied by a normal thickness of the adrenal gland, respectively. The precision of the CT scan, adrenal scintigraphy and determination of plasma aldosterone in the adrenal or renal veins were almostly equal to the diagnosis of the localization of adrenal ademona.
It is concluded that the CT scan is a noninvasive and most useful method for the localization of aldosterone-producing adenoma and helpful in distinguishing adrenal adenoma from adrenal hyperplasia.

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Autonomic neuropathy is one of the complications of diabetes, and several lines of evidence, supporting that sympathetic neural dysfunction may play the major role in the orthostatic hypotension (OH) of diabetic patients have been presented.
In this paper the responses of plasma norepinephrine (PNE), plasma renin activity (PRA) and plasma aldosterone (PAC) to upright standing were studied in 17 diabetic patients without OH, 25 diabetics with OH and 17 age-matched, non-diabetic normotensives (controls). All were kept on a 200mEq sodium diet. Assay procedure for PNE was high-performance liquid chromatography with trihydroxyindol method and fluorimetric detection using dihydroxybenzylamine as internal standard. Intra- and inter-assay coefficient variations by this method were 3.4 and 5.8% respectively. PRA and PAC were determined by radioimmunoassay. Total blood volume was examined by the plasma tracer method using 131 I-HSA and expressed in percent normal.
Mean PNE level in the non-diabetic controls was 217pg/ml in recumbency and in-creased to a level of 551 at 15 minutes on standing. The PNE responses to standing in the diabetic subjects without OH (defined- as group I) were not significantly different from those in the controls. In the diabetics with OH, 14 cases, with the PNE increments less than 1SD below the mean in the controls, were defined as group III, and discriminated from other 11 subjects with OH (group II). PNE levels in group III were significantly lower than in the controls at both recumbency and upright posture. PRA was significantly elevated by standing in the controls and the diabetics except for group II. PRA in all the diabetic groups was significantly lower than in the controls, at both recumbent and upright. The mean values of PAC in the diabetics but group II at supine were significantly lower than those of the control group. PAC levels increased after standing contemporaneously with PRA, though significant rise in group II was shown without PRA response. Total blood volume was significantly (p<0.025) decreased in only group II.
The results suggest: 1) PNE was normal in the diabetic patients without OH, 2) there are at least two types of OH in diabetes mellitus: one is hypoadrenergic and the other hypovolemic, 3) adrenergic neuropathy may be a cause of low PRA in diabetics with OH but another factor may also be involved in both with and without OH, 4) low PRA is a main factor of low PAC in diabetics (group I and III), but the dissociation between PRA and PAC responses to orthostasis is present in some cases (group II), which reflects disturbances in other regulatory mechanisms of aldosterone secretion.

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Sympathetic nervous system may play an important role in the pathogenesis of essential hypertension. The present study was undertaken to evaluate the interaction between sodium intake and sympathetic nervous activity in the patients with essential hypertension. Plasma and urinary catecholamines (CA) were measured in 38 hypertensive patients (WHO 1-2 stage) and 24 age-matched normal subjects on regular (urinary sodium excretion (U_NaV): 133 ± 8mEq/day; mean ± SEM), high (U_NaV 317 ± 90mEq/day), and low (U_NaV 67 ± 28 mEq/day) sodium diets for each 5 days at random. CA were analyzed by THI methods after HPLC separation. Twenty-four hour urinary norepinephrine (NE), epinephrine (E), and electrolytes (Na⁺, K) excretion on the 5th day of each regimen were determined. In the 6th day morning supine and 5 min upright plasma NE(PNE), plasma E (PE), and plasma renin activity were determined after blood pressure and pulse rate measurement. The results were also analyzed according to the difference between salt-sensitive and non-salt-sensitive type of hypertensive patients.
Plasma NE was 1.1 ± 0.4 p mol/ml (supine), 1.5 ± 0.4 p mol/ml (upright) in normo-tensive subjects and 1.8 ± 1.1 p mol/ml (supine), 2.5 ± 1.1 p mol/ml (upright) in the patients with essential hypertension, 24 hr urinary NE excretion were 116 ± 54μEg/day in normotensive subjects and 138 ± 88μEg/day in the patients with essential hypertension on regular sodium intake. Mean plasma NE levels in patients with essential hypertension were always higher than those in normotensive subjects on any sodium diets. Plasma NE and urinary NE were significantly reduced by high sodium intake and increased by low sodium intake in both normotensive subjects and the patients with essential hypertension. Percentile decrease in PNE when the diet was changed from low sodium to high sodium was much greater in normotensive subjects than the patients with essential hypertension. These tendency was observed in both salt-sensitive and non-salt-sensitive hypertensive patients. How-ever, PNE in non-saltsensitive hypertensive subjects tended to be higher than those in salt-sensitive hypertensive subjects.
These results suggest that abnormal relationship between sodium intake and sympathetic nervous system may play an important role in the pathogenesis of essential hypertension.

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Insulin-effects on adenylate cyclase activity, cyclic AMP (cAMP) content and free fatty acid (FFA) accumulation of rat epididymal fat cells were examined under conditions of maximal inhibition of phosphodiesterase by sufficient amounts of theophylline for the purpose of localizing the site of the antilipolytic action of insulin. After brief preincubation of the cells with physiological amounts of insulin in the presence or absence of 0.1mM adrenalin, fat cells were homogenized following the addition of theophylline and then further incubated. Under these conditions, small but significant enhancement of adenylate cyclase activity, cAMP content and FFA accumulation by insulin alone was observed, while insulin remarkably inhibited adrenalin-stimulated FFA accumulation, reducing adenylate cyclase activity and cAMP levels. This increase of cAMP content by insulin was only seen 5 or 15 minutes after the addition of theophylline. Furthermore, this insulin effect was also observed in the experiments which were performed in a medium containing high concentrations of albumin (2%). The concomitant accumulation of FFA might have resulted from the stimulation of lipolysis, rather than from the synthesis of FFA, since there was no added glucose in the medium. And finally, the hydrolysis of ¹⁴C-tripalmitate by a fraction of the cell homogenate under the presence of theophylline was more extensive after pre-incubation of the cells with insulin than without insulin.
In summary, insulin, which is recognized as a typical antilipolytic normone, activatea adenylate cyclase and increased lipolysis at its physiological concentrations when it alone exerted its effect upon fat cells under the conditions where phosphodiesterase was completely inhibited by theophylline. Accordingly, the present results indicate the bimodal effect of insulin on adenylate cyclase and lipolysis under the presence of theophylline; enhancement when applied alone, and depression with adrenalin. So it is most likely that the “negative synergism” occurs as a net effect when a mild activator acts together competitively with a strong activator toward the same target. These data suggest the fundamental roles of adenylate cyclase systems in the mechanism of lipolysis regulation by insulin.

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In order to make a statistical survey of Japanese patients with pseudohypoparathyroidism and related diseases, we defined the diagnostic criteria for seven disease states described below. The criteria were mainly based on practical data readily available at standard hospitals.
In the text, the seven diseases are described separately in the order of a) definition or conception, b) pathophysiology, c) proposed diagnostic criteria, d) comments on the diagnostic criteria.
The diseases are (1) Pseudohypoparathyroidism Type I, (2) Pseudohypoparathyroid-ism Type II, (3) Pseudohypo-hyperparathyroidism, (4) Pseudopseudohypoparathyroidism, (5) Pseudoidiopathic hypoparathyroidism, (6) Vitamin D dependency type I and (7) Hypo-phosphatemic vitamin D resistant rickets.
Based on these diagnostic criteria, a nation-wide investigation on patients with these diseases was performed (The detailed report will appear in a separate paper). The results indicated that these criteria are of considerable value in establishing diagnoses from question-naires answered by practicing physicians.

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