Non-invasive assessment of the age related changes in stiffness of major branches of the human arteries

The static mechanical properties of major branches of the human arteries (common carotid artery, abdominal aorta, femoral artery, and brachial artery) were studied in 39 subjects, aged 6-81 years, using an ultrasonic phase locked echo tracking system that allows continuous transcutaneous measurement of the diameter of the artery. The stiffness indices were calculated from the relation between systemic blood pressure and arterial diameter. With advancing age there was a significant increase in the diameter of all arteries with a reduction in percentage change in diameter. The stiffness index increased with age in all arteries; however, in the brachial and femoral arteries there was considerable variation in the individual values for a given age. The age associated increase in stiffness was statistically significant only in the common carotid artery and the abdominal aorta. Although the mechanical properties of the peripheral arteries were significantly influenced by the measuring environment, the calculated stiffness indices were less vulnerable to these stimuli in the central arteries. These results indicate that the stiffness indices of the peripheral muscular arteries are modified appreciably by vasoactive stimuli and that the mechanical properties of the deeper elastic arteries provide sufficiently reliable information about changes caused by aging and arteriosclerosis. The new ultrasonic method used appears to be suitable for this analysis.

[Clinical studies on cefuzonam in the field of obstetrics and gynecology]

Cefuzonam (CZON, L-105), a cephem type antibiotic, was clinically studied in the field of obstetrics and gynecology. The results are summarized as follows: CZON 1-2 g was administered by injection twice daily to 11 cases of infections (4 of endometritis, 2 of pyometra, 3 of adnexitis and peritonitis, 1 of abdominal abscess, and 1 of puerperal fever). Clinical efficacy was excellent in 2 cases and good in 9 cases, with a very high overall efficacy rate of 100%. Slight elevations of GOT and GPT in 1 case were noted in clinical laboratory tests. No side effects attributable to the drug were noted. CZON is considered to be a useful drug for obstetric and gynecological infections.

Effects of nipradilol, a new beta-adrenoceptor blocking agent with vasodilating properties, on transmural energy metabolism in the underperfused canine heart

Effects of nipradilol on hemodynamics and transmural energy metabolism of underperfused (ischemic) canine hearts were investigated. The ischemic heart was prepared by constricting a tube connecting the circumflex coronary artery with the carotid artery for 10 min so that the perfusion pressure (CPP) was reduced to 30 mmHg. The reduction in CPP resulted in decreases in coronary blood flow (CBF) by 70%, regional myocardial contractile force (MCF) by 30%, myocardial ATP contents by 32% (inner layer)-22% (outer) and creatine phosphate by 75% (inner)-60% (outer). Increases in the left ventricular end diastolic pressure (LVEDP) by 4.8 mmHg, myocardial inorganic phosphate contents by 1.9 times (inner)-1.3 (outer) and lactate by 4.3 times (inner)-2.4 (outer) were also observed. In dogs with normal hearts, an infusion of nipradilol (10 micrograms/kg/min, i.v., for 15 min) decreased CPP by 25%, CBF by 40%, cardiac effort index by 45% and MCF by 30 to 40%, and it slightly increased LVEDP without affecting myocardial high-energy phosphate and lactate levels. In ischemic hearts, nipradilol infusion starting 5 min before ischemia attenuated the ischemia-induced elevation of LVEDP to 1.8 mmHg, and the ischemia-induced changes in high-energy phosphate contents to 1/2 (inner)-1/3 (outer) and changes in lactate to 1/6 (inner)-1/10 (outer). These results indicate that nipradilol improves the ischemic derangement of both transmural energy metabolism and hemodynamics.

Influences of an infusion of lipid emulsion on phagocytotic activity of cultured Kupffer's cells in septic rats

An experimental study was undertaken to study the influences of an infusion of lipid emulsion on phagocytosis of Kupffer's cells in septic rats. Sepsis was induced in 13 rats by ligating the cecum. Five of them received glucose as the sole nonprotein calorie (septic-glucose group), four of the rats received 25% of the nonprotein calorie with lipid emulsion, Intralipid (septic-lipid group), and the remaining four rats did not receive any intravenous solution and were allowed access to water (septic-fasted group). Another four rats which received neither intravenous solution nor ligation of the cecum served as the control group. The intravenous infusion was carried out for 72 hr. The phagocytotic activity of Kupffer's cells was determined by the ability to engulf latex particles with a size of 1.09 micron, in vitro. The phagocytotic activity was enhanced by the presence of sepsis but it was inhibited by starvation. The difference in the phagocytotic activity between the septic-glucose group and the septic-lipid group was not significant. These results suggest that, insofar as an in vitro study is concerned, a 72-hr infusion of lipid emulsion at a rate of 25% of the total nonprotein calorie does not influence the phagocytotic activity of cultured Kupffer's cell obtained from septic rats.

Effects of total parenteral nutrition on the development of intestinal endotoxemia in rats: a comparison between glucose and lipid

The effects of parenteral nutrition (PN) and of the difference in the PN regimens between glucose and lipid emulsion on the development of endogenous endotoxemia were studied in 40 Wister rats. Endotoxemia was induced by occluding the superior mesenteric vein (SMV) for 30 min. The plasma endotoxin in the portal blood at the time of the release of the SMV occlusion and that in the arterial blood 10 min after the release were quantified. Twenty of the 40 rats had received PN for 48 hr prior to the SMV occlusion. Ten of these 20 rats received the total nonprotein calorie (TNPC) solely with glucose, and the other 10 rats received 25% of the TNPC with lipid emulsion. Ten rats had been allowed free access to lab food until the SMV occlusion. The remaining 10 rats underwent neither the SMV occlusion nor PN, and served as the control group. Both the portal and the arterial endotoxin increased after the release of the SMV occlusion, however the portal endotoxin was higher than that of the arterial one. Both the portal and the arterial endotoxin of the rats supported by PN were significantly lower than those of the rats nourished by lab food, while they were higher than the control values. The difference in the PN regimens did not cause any alteration in the endotoxin levels. These results indicate that the development of intestinal endotoxemia was not influenced by the difference in the PN regimens, but it was rather influenced by a presence of intestinal content.

Inhibition of catalytic unit of adenylate cyclase and activation of GTPase of Ni protein by beta gamma-subunits of GTP-binding proteins

A protein factor which inhibited adenylate cyclase was purified to apparent homogeneity from rat brain and identified as the beta gamma-subunits of the GTP-binding regulatory proteins of adenylate cyclase. (i) The beta gamma-subunits (protein factor) inhibited the partially purified catalytic unit of adenylate cyclase in the presence of an activator, forskolin or the stimulative regulatory protein (Ns), to 60 and 40% of the control, respectively; inhibition of the catalytic unit in the presence of forskolin required no guanine nucleotides. (ii) The subunits enhanced the GTPase activity of the purified alpha-subunit of the inhibitory regulatory protein (Ni alpha) 3.8-fold. (iii) The subunits stimulated ADP-ribosylation of Ni alpha catalyzed by islet-activating protein (pertussis toxin). ADP-ribosylation had no effect on the GTPase activity of Ni alpha in the presence of the beta gamma-subunits. The results suggest that direct inhibition of the catalytic unit by the beta gamma-subunits liberated from Ni is essential for the receptor-mediated inhibition of adenylate cyclase.

GTPase activity associates with the inhibitory GTP-binding regulatory component of adenylate cyclase purified from rat brain

The inhibitory regulatory component of adenylate cyclase (Ni) was highly purified from rat brain synaptic membranes. A low Km GTPase activity was always associated with Ni through the purification, and the recovery of GTPase activity correlated well with that of Ni. Purified Ni was hardly ADP-ribosylated by islet-activating protein (IAP). A heat-labile factor in the fraction of the stimulative regulatory component (Ns) restored ADP-ribosylation and also activated the GTPase about 2-fold. NaF which was reported to interact with Ni markedly reduced GTPase activity. The purified Ni fraction inhibited adenylate cyclase only in the presence of a heat-stable factor found in the partially purified regulatory component. GTPase and inhibitory activities were weak in myelin which contained only a small amount of Ni. These findings support the view that GTPase activity is an intrinsic activity of Ni and some factors are necessary for the function of Ni.

Inhibitory effect of MgATP on the release of regulatory light chain from scallop myosin and light chain composition of scallop myosin hybridized with abalone light chain 2 at 30 degrees C

The experimental conditions for release of the regulatory light chain (RLC) of scallop myosin at 30 degrees C were studied. Substantially all RLC was released from myosin by incubation for 5 min in medium containing buffer and KCl. This release of RLC was inhibited strongly by Ca2+, while the effect of Mg2+ was about 10,000 times weaker than that of Ca2+. Even in the absence of Ca2+, MgATP and MgADP inhibited the release of RLC, while the protective effect of AMPPNP was negligible. Other Mg nucleotides also showed some protective effect, though appreciably less than MgATP. The incubation of scallop myosin with abalone regulatory light chain (LC2) at 30 degrees C for 5 min produced a hybrid myosin. In the presence of 5 mM MgCl2, 1 of the 2 mol of RLC per mol of scallop myosin was exchanged with 1 mol of LC2. In the presence of Ca2+ or MgATP, myosin bound 1 extra mole of LC2 besides the 2 mol each of SH-LC and RLC.

Catecholamine sensitivity and cardiac myosin ATPase activity in dogs treated with propranolol

The effects of propranolol treatment on adrenoceptor reactivity and on cardiac myosin ATPase activity have been studied. Eight mongrel dogs weighing 8 to 14 Kg were given propranolol orally 3 times daily (10 mg/Kg/day) for 2 weeks. Although the levels of propranolol were effective and there was a significant decrease in resting heart rate, there was no evidence of a rebound adrenoceptor hypersensitivity after abrupt withdrawal of propranolol treatment. The responsiveness of cardiovascular systems to 1-isoproterenol (1-ISO) was significantly attenuated 15 hrs after the last medication, but it did not differ from the premedication levels 6 days after discontinuation of medication. The effects of 1-ISO on adenylate cyclase activity in the myocardial membrane preparations were not significantly different between the 3 groups (no medication, 1 day and 6 days after discontinuation). With propranolol treatment, though a rise in total plasma catecholamine (norepinephrine, epinephrine, dopamine) levels was the predominant change, there were no definite changes in respective catecholamines. Serum triiodothyronine (T3) increased during medication in 7 of the 8 animals and decreased after medication. Calcium-activated and K+-activated myosin ATPase activity in the inner and outer layers of the left ventricular wall were uniform in unmedicated dogs, and propranolol produced no significant effects. No reliable evidence for propranolol withdrawal syndromes was provided in the present study.

Evidence for the presence of GTP-dependent regulatory component of adenylate cyclase in myelin from rat brain

A GTP-dependent regulatory component of adenylate cyclase was found in myelin from rat brain. The fraction solubilized from myelin contained a component that reconstituted guanine nucleotide-responsive adenylate cyclase activity when combined with the catalytic unit of adenylate cyclase prepared from rat brain. Purified myelin demonstrated little adenylate cyclase activity, even in the presence of F- or Mn2+. The reconstituted activity was dependent on the amount of the solubilized myelin fraction and required the presence of 5'-guanylylimidodiphosphate, a hydrolysis-resistant analog of GTP. The elution pattern of the component solubilized from myelin in gel filtration was very similar to that of a GTP-dependent regulatory component from synaptic plasma membranes. The content of the regulatory component-like activity in myelin was estimated to be 50-60% of that in synaptic plasma membranes. Cholera toxin ADP-ribosylated proteins having molecular weights of 48,000, 38,000, 23,000, 20,000, and 15,000 and other minor peptides in myelin, some of which were also present in synaptic plasma membranes. We conclude that myelin contained a GTP-dependent regulatory component of adenylate cyclase despite the apparent lack of adenylate cyclase activity in myelin.

Effects of pentobarbital anesthesia on the plasma catecholamines and renin activity as reflected in the hemodynamic changes in dogs

Correlation between hemodynamic changes and plasma catecholamines or renin activity were studied in dogs anesthetized with pentobarbital, 30 mg/kg, i.v. Pentobarbital increased heart rate in all cases regardless of changes in plasma catecholamines, and the increase was not depressed fully by propranolol. Blood pressure (BP) showed a transient decline just after pentobarbital injection and then elevated gradually to one of three levels 30-60 min after anesthesia. In low (62 +/- 4 mmHg, Mean +/- S.E.) and very high BP (169 +/- 7 mmHg), plasma norepinephrine (NE) showed low (305 +/- 55 leads to 89 +/- 22 pg/ml) and high levels (296 +/- 54 leads to 372 +/- 106 pg/ml), respectively, which probably reflect the neurosympathetic activities. In moderately high BP (112 +/- 4 mmHg), however, the hypertension did not necessarily reflect changes in plasma NE. When the level before anesthesia was 108-164 pg/ml, plasma NE increased, whereas it decreased when the level was 182-374 pg/ml. In either case, the level was fixed within 117-182 (154 +/- 6) pg/ml. Plasma renin activity increased after anesthesia and maintained for at least 2 hr. However, the increase were observed regardless of the BP level, and moderately high BP was not depressed by an angiotensin II antagonist. Participation of angiotensin in these sustained BP cases seems unlikely. Plasma epinephrine reflecting adrenal-medullary activity was decreased markedly in all cases, and the low level lasted for at least 2 hr. Changes in plasma dopamine are related to those in plasma NE, and the origin seems to be the same.

Separation and properties of a regulatory GTPase activity associated with the adenylate cyclase system in rat brain synaptic plasma membranes

A GTPase activity having a Km value of 0.5 microM was present in synaptic plasma membranes from rat brain. The activity was inhibited 63% and 24% by NaF and cholera toxin respectively and solubilized from the membranes together with the adenylate cyclase activity. Upon gel chromatography, the solubilized GTPase activity was co-eluted with the GTP-binding regulatory protein of adenylate cyclase. A similar GTPase activity was also associated with the regulatory protein from myelin. The regulatory protein fraction enhanced the activity of the catalytic unit of adenylate cyclase in the presence of 5'-guanylylimidodiphosphate but inhibited the adenylate cyclase activity by 70% in the presence of GTP. These results indicate the possible involvement of the GTPase activity in the regulation of the adenylate cyclase activity.

Chromosomal analyses after in vitro fertilization of squirrel monkey (Saimiri sciureus) oocytes

The effect of 1 microM dibutyril cAMP (cAMP media) on the chromosomal normality of in vitro fertilized squirrel monkey oocytes was examined. A total of 877 oocytes were collected laparoscopically 15-16 h after hCG injection from hormonally-induced follicles of 65 squirrel monkeys. Of these, 330 (37.6%) were prepared between 6 and 30 h after insemination and analyzed. Sperm penetration and the presence of a swollen sperm head in the ooplasm were observed by 6 h, and the nucleate stage by 10 h. Addition of 1 microM dbcAMP did not affect the oocyte maturation rate, however the in vitro fertilization rate was increased 26.5% over controls (46.3 vs. 36.6%). The first cleavage metaphase was found at 16 h after insemination. Between 24 and 30 h post-insemination, 76.6% of fertilized oocytes had reached the first cleavage metaphase. An incidence of triploidy (including dispermy) of 11.7% was observed. After chromosomal analysis of metaphase I, univalents were observed in 16.7% of the cases. Aneuploidy (8.9%) was also found in metaphase II. Of the first cleavage metaphases, 88.0% had the diploid number of chromosomes. Aneuploidy occurred 12.0% of the time and 5 cases of triploidies were observed.

Light chains of abalone myosin. UV absorption difference spectrum and resensitization of desensitized scallop myosin

1. Abalone myosin consisted of one kind of heavy chain and two kinds of light chain according to SDS gel electrophoresis. The molecular weights of the light chains were estimated as 16,600 daltons (Light Chain-1: LC-1) and 14,500 daltons (Light Chain-2: LC-2). 2. The amino acid composition of LC-2 was not appreciably different from that of LC-1 except that the valine residue was 1 mol per mol of LC-2. 3. both LC-1 and LC-2 showed a calcium-induced UV absorption difference spectrum through the apparent binding constants for Ca2+ were low (2.5 x 10(-3) M for LC-1 and 3.2 x 10(-4) M for LC-2). 4. The modification of carboxyl groups of LC-2 by 1-ethyl-3(3-dimethylaminopropyl)carbodiimide caused the disappearance of the calcium-induced UV absorption difference spectrum. 5. Manganese ion could also induce a UV absorption difference spectrum with these light chains although the concentration of Mn2+ required to produce the difference spectrum was very high. 6. Abalone LC-2 bound to desensitized scallop myosin and restored the calcium sensitivity of the myosin but LC-1 did not.

Difference UV-absorption spectrum of scallop adductor myosin induced by ATP

A difference UV-absorption spectrum induced by ATP was observed with scallop myosins purified from both striated and smooth adductor muscles. The difference spectra showed a positive peak at 289 nm with a shoulder around 295 nm, and two small negative troughs around 280 nm. Tryptophanyl movement similar to that in rabbit skeletal myosin is indicated. Some tyrosyl movements in scallop myosins, however, may be in the opposite direction.

Epinephrine-induced elevation of guanosine 3':5'-cyclic monophosphate in isolated fat cells of rat

The effects of epinephrine (as low as 0.1 muM) on guanosine 3':5'-cyclic monophosphate (cGMP) and adenosine 3':5'-cyclic monophosphate (cAMP) in isolated fat cells were examined. Epinephrine increased both cGMP and cAMP levels, with the elevation of cAMP preceding the rise of cGMP. Maximal elevation was obtained with 1 muM epinephrine for each nucleotide. The increase in content of cGMP and cAMP due to epinephrine was completely blocked by a beta-adrenergic antagonist (5 muM propranolol). Phentolamine (10-100 muM), an alpha-adrenergic antagonist, enhanced the response to epinephrine resulting in elevation of cAMP levels, whereas a high concentration (100 muM) of phentolamine suppressed the elevation of cGMP. The ability of epinephrine to increase cGMP and cAMP levels was markedly diminished by "feedback regulator" partially purified from the incubation mixtures of isolated fat cells exposed to epinephrine [Ho, R.J. & Sutherland, E. W. (1971) J. Biol. Chem. 246, 6822-6827], whereas an increase in cGMP, but not cAMP, levels was observed in isolated fat cells incubated with "feedback regulator" alone (without epinephrine). These observations suggest the possibility that the epinephrine-induced elevation of cGMP levels in isolated fat cells might be mediated by an increase in formation of intracellular "feedback regulator" due to an elevation of cAMP by epinephrine.