High systolic blood pressure increases prevalence and severity of retinopathy in NIDDM patients.

OBJECTIVE: To determine whether the severity of retinopathy is higher in a group of NIDDM patients with sBP greater than or equal to 140 mmHg compared with NIDDM patients with sBP less than 140 mmHg. RESEARCH DESIGN AND METHODS: Ophthalmoscopy and FAG were conducted among a group of NIDDM patients with either a sBP above (n = 54) or below (n = 55) 140 mmHg. The groups were matched according to diabetes duration, metabolic control (HbA1c), and AER. RESULTS: Patients with sBP greater than 140 mmHg had a higher prevalence of retinopathy, as established according to a rating scale (4.9 +/- 3.8 vs. 3.2 +/- 3.3, P less than 0.02); furthermore, their BMI values were higher (28.1 +/- 4.5 vs. 24.9 +/- 4.1 kg/m2, P less than 0.001). The group of normotensive subjects showed the highest rate of low grading (0-2) values. However, the highest prevalence rates of 8-10 grading values (proliferative retinopathy) were found in the hypertensive group. CONCLUSIONS: These data suggest that sBP values greater than or equal to 140 mmHg favor the onset of retinopathy in NIDDM patients during their 1st 10 yr of disease.

Gallbladder volume and emptying in diabetics: the role of neuropathy and obesity.

Gallbladder (GB) volume was monitored by real-time sonography in diabetics (n = 21) and healthy volunteers (n = 55) after a test meal. Seventeen controls and seven diabetics were obese; six patients had both autonomous and somatic neuropathy, and four had somatic neuropathy. Fasting GB volume was similar in controls and diabetics with and without autonomic neuropathy; it was correlated with body mass index (controls, r = 0.43, P less than 0.002; diabetics, r = 0.46, P less than 0.04), and was increased in obese subjects. Post-prandial GB emptying was decreased in diabetics. Those with autonomous neuropathy exhibited larger residual volumes than controls (P less than 0.03). Post-prandial GB emptying was slower and less complete in (non-diabetic) obese subjects and deteriorated further in diabetic obese subjects. GB fasting tone was normal, but GB kinetics were impaired in diabetics; obesity and autonomous neuropathy were correlated with GB hypomotility.

Changes in overall plasma norepinephrine turnover and lymphomonocyte beta-adrenoceptor number during combined caloric and sodium restriction in normotensive obese subjects.

The aim of the study was to evaluate in eight normotensive obese patients the influence of low sodium intake (9 mEq/day) on the sympathetic activity modifications induced by caloric restriction (2511 kJ/day). As compared to the isocaloric salt balanced diet, 7 days of normosodic underfeeding induced a decrease in the overall norepinephrine turnover (clearance and appearance rate) and 24 hours urinary output, whereas the combined caloric and salt restriction significantly increased the norepinephrine appearance rate and even more the norepinephrine clearance but, on the other hand, decreased the beta-adrenergic receptor number on the lymphomonocyte surface, suggesting a reduced peripheral sensitivity to catecholamines. Therefore, the utility of the combined sodium and caloric restriction in the treatment of the normotensive obese patients remains still questionable.

Atrial natriuretic peptide protects against acute ischemic renal failure in the rat.

Because of its ability to increase glomerular filtration, antagonize the actions of vasoconstrictors, and produce vasodilation, alpha human atrial natriuretic peptide (alpha-hANP) was evaluated for its potentially beneficial effects in experimental ischemic renal failure induced by 45-60 min of renal artery occlusion in bilaterally or unilaterally renally intact Sprague-Dawley rats. After ischemia, a 4-h intrarenal infusion of alpha-hANP restored 14C-inulin clearances in bilaterally and unilaterally intact animals from 0.05 +/- 0.006 and 0.05 +/- 0.01 ml/min per 100 g to 0.314 +/- 0.04 and 0.25 +/- 0.01 ml/min per 100 g, respectively (P less than 0.001, n = 8), compared with normal values of 0.49 +/- 0.023 ml/min per 100 g. Histologically, there was a progressive decrease in medullary hyperemia and prevention of intratubular cell shedding and granulocyte margination as a result of the 4-h alpha-hANP infusion such that after 24 and 48 h the histological appearance of the tissue was essentially normal. The results show that a 4-h intrarenal infusion of alpha-hANP after renal ischemia can preserve glomerular filtration rate and reduce renal tissue damage.

Arginine-vasopressin response to supine-erect posture change: an index for evaluation of the integrity of the afferent component of baroregulatory system in diabetic neuropathy.

The arginine-vasopressin (AVP) response to supine-standing postural change was evaluated in eight healthy subjects and in fourteen diabetic patients. Plasma AVP levels were found to increase in the controls and in nine subjects from the diabetic group. In the controls the increase was 139% 5 min. after standing and 275% 120 min. after standing. In four of the diabetics affected by autonomic neuropathy AVP failed to increase in response to standing, thus suggesting lesions of the neurogenic pathways connecting baroreceptors to neurohypophysis. Consequently, a failure of the afferent limb in the baroregulatory system must be taken into account among other localizations of autonomic neuropathy. On this basis, AVP measurement both in supine and erect positions could represent an additional test for assessing the integrity of the autonomic nervous system.