Antihypertensive effects of CI-907 (indolapril): a novel nonsulfhydryl angiotensin converting enzyme inhibitor

CI-907 is a new orally active nonsulfhydryl angiotensin converting enzyme (ACE) inhibitor. Monoester (prodrug) and diacid forms produced concentration related ACE inhibition in guinea-pig serum (IC50 for monoester, 1.7 X 10(-7) M and for diacid, 2.6 X 10(-9) M). In isolated rabbit aortic rings and in rat and dog autonomic studies, CI-907 is highly specific in suppressing the contractile or pressor responses to angiotensin I. In two-kidney, one-clip Goldblatt hypertensive rats, single daily doses (0.03-30 mg/kg p.o.) produced dose-dependent decreases in blood pressure; 3 mg/kg lowered blood pressure to normotensive levels. In the spontaneously hypertensive rat, subacute administration of CI-907 (30 mg/kg/day for 5 days) produced the same decrease in blood pressure as that obtained in the renal hypertensive rat. In diuretic-pretreated renal hypertensive dogs, 10 mg/kg normalized blood pressure. For equivalent drops in blood pressure, heart rate increases were less in CI-907 than in enalapril-treated renal hypertensive dogs. No side effects were observed with CI-907 in any of the conscious animals. The antihypertensive response to CI-907 (0.03-1.0 mg/kg p.o.) was found to correlate with inhibition of vascular tissue ACE, but not plasma or brain ACE in two-kidney, one-clip renal hypertensive rats. These studies indicate that CI-907 is a potent antihypertensive agent with a heart rate profile different from enalapril.

Selective effects of secretagogues on insulin secretion: a mathematical model

A mathematical model of the secretion of insulin from pancreatic islets of Langerhans is proposed. Previously proposed mathematical models of insulin secretion have dealt solely with glucose-stimulated release, and not with the more complex patterns of secretion (such as "off-responses") in response to other secretagogues or combinations of secretagogues. We conclude that an off-response is consistent with a compartmental model; and the facilitating effect of a constant concentration of glucose on leucine-stimulated insulin secretion is consistent with a selective effect of glucose on a single compartment of the model.

Management of pancreatic trauma

Twenty patients who sustained pancreatic trauma are reviewed. Eighteen of the patients underwent emergency laparotomy and there were 53 major associated injuries. Three patients died, giving an operative mortality of 17%. All deaths could be directly attributed to the severity and extent of the associated injuries. Eleven of the 15 survivors following emergency operation developed serious postoperative complications which, in 6 instances, were directly related to the pancreatic injury. Two patients were initially treated conservatively because the isolated pancreatic injuries were missed. Both developed complications requiring operation.

Survey of new antihypertensive drugs: 1982

Over 500 compounds reported to have antihypertensive activity have been cataloged from the world literature (1979-1982). The agents were classified according to mechanism: 1) drugs interacting at alpha-adrenoceptor sites; 2) beta-adrenoceptor antagonists; 3) drugs interacting with the autonomic nervous system by mechanisms other than 1 and 2; 4) inhibitors of the renin-angiotensin system; 5) diuretics; 6) vasodilator antihypertensives; and 7) drugs with miscellaneous mechanisms and/or sites of action. Within each class the drugs were subclassified and compounds that best fit the prototypes identified. The scheme is subjective, largely because of conflicting information cited in the literature. It is clear that many new drugs are at various stages of development. Whether or not these drugs will survive the scrutiny of rigorous and lengthy preclinical and clinical development, and in fact prove to be better antihypertensive agents than the currently marketed agents, remains to be established.

Potassium-induced vascular relaxation in two kidney-one clip, renal hypertensive rats

This study was designed to characterize potassium-induced relaxation in vascular smooth muscle in two kidney-one clip (2K-1C), renal hypertensive rats. Potassium-induced relaxation was evaluated in the isolated tail artery and in the isolated pump perfused renal vasculature. Both preparations relaxed in response to potassium after contraction induced by norepinephrine in potassium-free solution. Arterial preparations from hypertensive rats showed greater relaxation than did those from normotensive rats. Potassium-induced relaxation in tail arteries from hypertensive rats was more sensitive to ouabain inhibition than those from normotensive rats; the renal vasculature of hypertensive rats did not differ from controls with respect to ouabain sensitivity. Relaxation in response to potassium in isolated tail artery segments varied with the: 1. length of incubation in potassium-free solution; 2. concentration of added potassium; and 3. concentration of norepinephrine added during the potassium-free interval. The amplitude of potassium relaxation is believed to be a functional measure of the electrogenic sodium pump. These experiments support the hypothesis that vascular smooth muscle from 2K-1C renal hypertensive rats has increased electrogenic sodium pump activity, in vitro.

Systemic sarcoidosis presenting with Horner's syndrome and mandibular paresthesia

A patient with Stage I systemic sarcoid (affecting the mediastinum and cervical lymph nodes) is presented. This patient had ptosis of the eyelid and miosis (Horner's syndrome) due to involvement of the cervical-thoracic sympathetic nerves by the granulomatous process. Bony destruction simulating periodontal disease occurred in the molar-premolar region and caused pain and paresthesia. Systemic sarcoid may occur more commonly in the jaws than reported cases would indicate. Sarcoidosis should be considered in the differential diagnosis when periodontal disease appears refractory to local therapy.

Ectopic soft-tissue mesiodens

The mesiodens is the most common supernumerary tooth. It can be found in both the erupted and the impacted states. A case of a developing mesiodens located entirely in soft tissue is described. The lesion presented as a pedunculated palatal mass. No case of soft-tissue mesiodens has been previously reported. A theory of origin for this supernumerary tooth is proposed.

Nitroprusside-induced vascular relaxation in DOCA hypertensive rats

Vascular responsiveness to nitroprusside and to norepinephrine was examined in two different preparations from DOCA hypertensive and normotensive control Sprague-Dawley rats. The blood-perfused renal vasculatures of DOCA hypertensive rats were significantly more sensitive than those of normotensive controls to the vasodilator action of low doses of nitroprusside. At high doses, responses in DOCA hypertensive and normotensive rats were similar. Since basal "structural" vascular resistances were greater in the hypertensive rats, It is possible that further vasodilation with nitroprusside was impeded more in DOCA-treated than in control rats. Nitroprusside produced a greater degree of vascular smooth muscle relaxation in tail artery strips from DOCA hypertensive rats than in those from normotensive controls. The current study is the first characterization of the effects of a vasodilator in mineralocorticoid hypertension. The two preparations gave divergent results with respect to vascular sensitivity to norepinephrine. When compared with control rats, the DOCA hypertensive rats showed a greater sensitivity to norepinephrine in tail arteries but a lesser renal vascular reactivity. It is evident that one must take a number of variables into consideration when characterizing changes in vascular responses that occur in a given model of hypertension: 1) the region of the vasculature (renal vs caudal artery);2) the level of the arterial tree (conduit vs resistance vessels);3) the technique employed for measurement of vascular changes (smooth muscle contraction vs vascular resistance changes);4) the initial vasoconstrictor tone of the preparation; and 5) the agonist used (nitroprusside vs norepinephrine).

Phosphoethanolamine as a growth factor of a mammary carcinoma cell line of rat

We have identified phosphoethanolamine as the pituitary-derived growth-promoting material that specifically stimulates the rat mammary carcinoma cell line 64-24. We have been studying the growth characteristics of the 64-24 cell line, which was isolated from a highly hormone-dependent tumor and which retains in culture many characteristics of the original tumor. Previously, crude bovine pituitary extract was shown to contain a significant amount of growth-stimulating activity for these cells, and a growth factor from this extract was purified to homogeneity. This report describes the identification of the growth factor as phosphoethanolamine. Further, the biological activity of phosphoethanolamine was found to be virtually identical to that of the purified growth factor. A possible role of phosphoethanolamine in the growth of mammary tumor cells as well as of normal mammary epithelial cells and other tissues is discussed.

Cellular thin filament protein contents and force generation in porcine arteries and veins

We estimated the cellular myosin, actin, and tropomyosin contents of vascular smooth muscle from (1) seven major arteries, (2) seven large veins, and (3) the first through third order branches of the uterine vasculature to determine whether variations in the contractile apparatus contribute to the functional diversity of vascular smooth muscle. We obtained the estimates by quantitative densitometry of stained polyacrylamide gels after electrophoresis of sodium dodecyl sulfate-treated tissue homogenates. No differences in cellular myosin content were found (18.7 +/- 1.0 mg/g cell wet weight in arteries vs. 17.2 +/- 0.7 in veins). However, the actin and tropomyosin contents were higher in arteries (49.7 +/- 2.9 and 13.1 +/- 0.8 mg/g cell, respectively) than in veins (25.5 +/- 1.4 and 7.0 +/- 0.3 mg/g cell). These differences persisted in the smaller uterine vessels. The higher contents of thin filament proteins in arteries, compared with veins and several other smooth muscle tissues previously studied, may underlie the high force generating capacity of arterial smooth muscle.

Chemistry of heparitin sulfate and heparin from normal tissues and from patients with Hunter syndrome

Some structural features of heparitin sulfate excreted by patients with Hunter syndrome are described. It is shown, with the aid of heparitinases and heparinase from Flavobacterium heparinum, that the Hunter heparitin sulfate is a very complex structure composed of nine different disaccharide units containing regions akin to normal heparitin sulfate and regions akin the heparin. Two-thirds of the iduronic acid residues of Hunter heparitin sulfate are devoid of sulfate, contrasting with heparin in which most of the iduronic acid residues are sulfated. The isolation and characterization of the non-reducing ends of heparin and of the heparitin sulfates is also described. Based on these results the specificity of the heparinase and heparitinases as well as the biosynthesis of iduronic acid-containing heparin-like compounds is discussed.

Differences in cellular contractile protein contents among porcine smooth muscles: evidence for variation in the contractile system

Cellular myosin, actin, and tropomyosin contents and ratios were determined for arterial (carotid, aorta, and coronary), intestinal (circular and longitudinal), esophageal, uterine, and tracheal smooth muscles inthe pig. Tissue protein contents were estimated by densitometry of polyacrylamide gels after electrophoresis of sodium dodecyl sulfate-treated tissue homogenates. Cellular contractile protein contents were estimated by correction for extracellular spaces. Cellular myosin contents were similar in each tissue (average +/- 1 SEM = 19.6 +/- 0.8 mg/g cell wet wt). However, the cellular contents of the thin filament proteins, actin and tropomyosin, were significantly higher in the arteries than in the nonarterial tissues. The calculated weight ratios of actin: myosin averaged 2.6 +/- 0.2 in the three arterial tissues and 1.5 +/- 0.1 in the nonarterial tissues, which may be compared with 0.36 in vertebrate striated muscles. The actin:tropomyosin weight ratios for all tissues were 3.7 +/- 0.1, a value comparable to the skeletal muscle ratio. The physiological implications of variations in the cellular thin filament protein contents are unknown, but these variations probably contribute to the observed differences in contractile function among various smooth muscles.

Differentiation of mucopolysaccharidoses by analyses of the excreted sulfated mucopolysaccharides

Analyses of sulfated mucopolysaccharides excreted by patients with Hunter, Hurler, Scheie, Sanfilippo A and Sanfilippo B syndromes are reported. Three distinct methods, namely agarose gel electrophoresis, enzymatic degradation and molecular weight determination, were used in an attempt to differentiate the mucopolysaccharidoses by analysis of the urinary mucopolysaccharides. It is shown that by the combination of these methods it is possible to differentiate most of the syndromes and also to demonstrated that some patients with the same syndrome excrete different types of sulfated mucopolysaccharides.

High-pressure liquid chromatographic analysis of polythiazide in pharmaceutical tablet formulations

A high-pressure liquid chromatographic method was developed for the quantitative determination of polythiazide in pharmaceutical tablet formulations after extraction of the powdered tablets with a water-acetonitrile solvent. Analysis is a accomplished by comparison of peak areas after chromatography.

High-pressure liquid chromatographic determination of thiothixene in pharmaceutical formulations

A method was developed for the quantitative determination of thiothixene in pharmaceutical formulations by high-pressure liquid chromatography after dissolution of the sample in methanol.

High-pressure liquid chromatographic determination of chlorpropamide in tablet formulations

A method was developed for the quantitative determination of chlorpropamide in tablet formulations by high-pressure liquid chromatography after homogenization of the sample with methanol.