Blood biochemical characteristics of cattle at sea level and at moderately high altitude (3,000 m).

We investigated the biochemical composition of blood from Holstein cows, native breed (criollas), and cows descended from fighting bulls (Vacas de lidia) raised at an altitude of 3,000 m (moderately high altitude, MHA), and compared the results with those from Holsteins and cows of similar genetic ancestry as the criollas (scrub cows), both raised at sea level (SL), to determine blood biochemical values characteristic of adaptation to high altitude. Only potassium and calcium concentrations were similar among groups. Glucose concentration was lower in MHA cows, with the exception of Vacas de lidia.

Hypothalamo-hypophyseal thyroid and gonadal function before and after erythropoietin therapy in dialysis patients.

We examined the effects of administration of two hypothalamic neurohormones, TRH and GnRH, for 3 days in five anemic male dialysis patients and five age-matched normal male volunteers. Patients on chronic hemodialysis have abnormal hypothalamo-hypophyseal thyroid and gonadal functions, including blunted TSH response to TRH, hyperprolactinemia, elevated basal levels of LH with exaggerated response to GnRH, and depressed FSH secretory response to GnRH. After correction of anemia with exogenous erythropoietin, these dialysis patients were given a single injection of the same hypothalamic hormones.

Protein kinase C(19-31) pseudosubstrate inhibition of insulin action in rat adipocytes.

Treatment of intact adipocytes with the autoregulatory PKC pseudosubstrate PKC(19-31) inhibited insulin-stimulated hexose uptake and lipogenesis, with no effect on basal values. The effect was dose-dependent with respective IC50 values of 30 microM and 600 microM for insulin-stimulated hexose uptake in electroporated and intact adipocytes. These studies indicate that PKC may play a role in the mediation of insulin action in adipocytes.

Cyclosporine-induced alterations in the hypothalamic hypophyseal gonadal axis in transplant patients.

We evaluated the response of 20 male patients, 13 cadaveric kidney and 7 heart transplant recipients, to the administration of 100 micrograms GnRH (gonadotropin-releasing hormone) and 500 micrograms TRH (thyrotropic-releasing hormone). All of the heart transplant recipients and 7 of the kidney transplant patients were receiving a combination of cyclosporine, azathioprine and prednisone; while the 6 remaining kidney transplant patients received azathioprine and prednisone. The patients receiving cyclosporine had decreased plasma levels of prolactin, and manifested a blunted response to TRH administration for prolactin and TSH.

The Hymenoptera venom study. III: Safety of venom immunotherapy.

One thousand four hundred ten (44%) of the 3236 subjects in the Hymenoptera venom study accepted venom immunotherapy (VIT). Time to maintenance averaged 95 days, and the largest number achieved maintenance (147 subjects, 10.4%) at day 56.

Protein kinase C activation patterns are determined by methodological variations. Studies of insulin action in BC3H-1 myocytes and rat adipose tissue.

In BC3H-1 myocytes, insulin has been reported to (a) increase diacyglycerol (DAG) production and provoke increases in protein kinase C enzyme activity of crude or DEAE-Sephacel-purified cytosol and membrane fractions in BC3H-1 myocytes (Cooper et al. (1987) J. Biol.

Low-dose captopril scintigraphy in the evaluation of renovascular hypertension.

This study compared the results of renal scintigraphy with simultaneous administration of Tc-99m DTPA and I-131 Hippuran (before and after 25 mg of oral captopril) with the results of the renal arteriogram and renal vein renins (before and after the administration of 25 mg of oral captopril) to evaluate the sensitivity and specificity of renal scintigraphy in the diagnosis of renovascular hypertension. The results of 21 consecutive patients suspected of having renovascular hypertension who underwent scintigraphy and renal arteriography were analyzed. Renal scintigraphy postcaptopril detected all the cases of renovascular hypertension (eight patients) plus two additional patients who had significant renovascular stenosis but no renin overproduction.

External calcium is required for activation of phospholipase C by angiotensin II in adrenal glomerulosa cells.

Previous studies have shown that external calcium (Ca2+) is required for the effects of angiotensin II (AII) on aldosterone secretion in adrenal glomerulosa zone. Using bovine adrenal glomerulosa cells prepared by collagenase dispersion, we examined whether external Ca2+ is required for the activation of phospholipase C by AII. Adrenal glomerulosa cells were exposed to Ca-EGTA buffered media to provide accurate estimates of external free Ca2+ concentrations.

Effects of insulin on diacylglycerol-protein kinase C signaling in rat diaphragm and soleus muscles and relationship to glucose transport.

Insulin was found to provoke rapid increases in diacylglycerol (DAG) content and [3H]glycerol incorporation into DAG and other lipids during incubations of rat hemidiaphragms and soleus muscles. Insulin also rapidly increased phosphatidic acid and total glycerolipid labeling by [3H]glycerol, suggesting that insulin increases DAG production at least partly through stimulation of the de novo pathway. Increased DAG production may activate protein kinase C (PKC) as reported previously in the rat diaphragm.

Mechanical ventilation with positive end-expiratory pressure decreases the circulating concentrations of the N-terminus and C-terminus of the atrial natriuretic factor prohormone.

Mechanical ventilation with positive end-expiratory pressure (PEEP) decreases urine output and urinary sodium excretion. The influence of PEEP during controlled mechanical ventilation on the circulating concentrations of the N-terminus and C-terminus of the atrial natriuretic factor (ANF) prohormone which both contain natriuretic and diuretic peptides was investigated in 7 patients with acute respiratory failure. The 98 amino acid (aa) N-terminus, the midportion of the N-terminus consisting of aa 31-67 of the 126 aa ANF prohormone (i.

Retention of specific protein kinase C isozymes following chronic phorbol ester treatment in BC3H-1 myocytes.

Since insulin effects on glucose transport persist in phorbol ester "desensitized" or "down-regulated" BC3H-1 myocytes, we reexamined the evidence for protein kinase C (PKC) depletion. After 24 hrs of 5 microM 12-0-tetradecanoyl phorbol-13-acetate (TPA) treatment, PKC-directed histone phosphorylation and acute TPA effects on glucose transport were lost, but PKC-dependent vinculin phosphorylation was still evident. Hydroxylapatite (HAP) chromatography revealed loss of a type III, but not a type II, PKC-dependent vinculin phosphorylation.

Pharmacokinetic and pharmacodynamic evaluation of propafenone in patients with ventricular arrhythmia. Propafenone Research Group.

Propafenone, a class IC antiarrhythmic agent, is metabolized into two active metabolites: 5-hydroxypropafenone (5-OHP) and N-depropylpropafenone (NDPP). In a placebo-controlled, double-blind study, we examined trough plasma concentrations of propafenone and its two metabolites in 169 subjects. Patients were randomized to one of five parallel treatment groups: placebo and 337.

Effects of dilevalol on rest and supine exercise hemodynamics in mild to moderate systemic hypertension.

Eight mildly to moderately hypertensive subjects free of any antihypertensive medications and on a normal salt diet performed maximal supine arm exercise. Before starting the exercise, a right-sided cardiac catheterization was performed to measure hemodynamic parameters before and during exercise. All patients had normal increases in cardiac output for the level of exercise performed and the peripheral vascular resistance diminished appropriately.

Occupational exposure to organic solvents causing chronic tubulointerstitial nephritis.

We describe a patient with a history of ulcerative colitis and long-standing occupational exposure to organic solvents. Over a follow-up period of almost four years he had progression of tubulointerstitial damage documented by two kidney biopsies. We propose that long-term exposure to organic solvents can lead to the development of chronic tubulointerstitial nephritis.

Regulation of aldosterone secretion during hypoxemia at sea level and moderately high altitude.

The aldosterone and cortisol responses to small doses of ACTH (0.125, 0.25, 0.

Counterregulatory hormonal response to insulin-induced hypoglycemia in patients on chronic hemodialysis.

Insulin induced hypoglycemia was produced in 5 chronic hemodialysis patients and 5 normal controls. Normally, several counterregulatory hormones (cortisol, growth hormone, glucagon and epinephrine) are secreted. Although we did not measure glucagon in our study, the other hormones were found to respond normally to the hypoglycemia in the control subjects.

Acute effect of captopril on aldosterone secretory responses to endogenous or exogenous adrenocorticotropin.

The aldosterone secretory response to Captopril (12.5 mg, orally) was studied in five normal men. Endogenous ACTH and epinephrine secretion was stimulated by the induction of hypoglycemia.