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In hog terminal bile duct cholecystokinin peptides caused an activation of cyclic AMP-dependent protein kinase (A-PK) with cyclic AMP, followed by increase in Ca uptake of sarcoplasmic reticulum fraction (SR-F). By contrast, papaverine showed no activation of A-PK-induced Ca uptake by SR-F with cyclic AMP. The Ca uptake by SR-F was dependent on ATP and Mg2+, but the component phosphorylated was not the phosphoenzyme intermediate in Ca2+-ATPase. The effect of Ca uptake was blocked by the inclusion of a protein inhibitor of A-PK. The correlation coefficient between cyclic AMP-dependent SR-F phosphorylation and stimulated Ca uptake by the phosphorylated SR-F was 0.731 (P less than 0.01). These results suggest that one of the mechanisms by which CCK-4, CCK-8, and CCK-33 peptides relax isolated Oddi's sphincters of terminal bile ducts is activation of A-PK-induced Ca uptake by sarcoplasmic reticulum fraction and possibly also by plasma membrane.

Growth of the test ofStrongylocentrotus intermedius was examined with the aid of tetracycline. In summer specimens, tetracycline fluorescence was not observable in the plates, except in the apical system and its adjacent area. An array of fibrous elements with a milky white autofluorescence was oriented perpendicularly to each suture line. In winter specimens the elements were evident only in demineralized sections. The growth gradient of each plate estimated on winter specimens was as follows: longitudinal sture » inner surface = mammelon and part of boss in tubercle > latitudinal suture > outer surface of base of spine shaft > outer surface of plate itself. The mature test as a whole increases in size by two modes of growth, an addition of new plates to the apical system and an accretion on fixed sites of each plate. The results suggest that fibrous elements are involved in the test growth, and that there is a different mechanism of the test growth between summer and winter specimens. The apical system may be equipped with a specific mechanism of calcification which permits an active formation of new plates throughout the year.

1. A comparison of the multiple markings labelled on scale, centrum and otolith of young goldfish was made by administering various amounts of tetracycline at intervals of one, two and three months. 2. For obtaining a clearly separate multiple pattern of the tetracycline fluorescence on every tissue of the scale, centrum and otolith of a fish, injections at intervals of more than two months are recommended to be appropriate. However, as for multiple markings on otolith only, injections may be successful even at an interval of one month. 3. A suitable amount of the tetracycline injection for young goldfish is considered to be 50mg. per kg. of body weight. 4. The intensity of the tetracycline fluorescence labelled on the otolith is found to correspond with the dosage administered, but is not always so on both the scale and centrum. 5. Even with the same dosage level administered, the tetracycline pattern on the scale is highly variable according to individuals and also to parts of the fish body. However, the patterns on the scales of central part of the flank along the lateral line was shown to be stable, at least, in the individuals with normal growth of body.

1. Distribution of the protein fractions of the extrapallial fluid of fourteen species of molluscs was determined by means of paper and cellulose acetate electrophoresis.2. The extrapallial fluid of species in which the calcium carbonate of the shell occurred as calcite contained a single protein fraction. In those species in which the shell calcium carbonate occurred as aragonite or as both aragonite and calcite, three or more protein fractions were present in the extrapallial fluid.

1,2,2-Tris(p-methoxyphenyl)vinylbromide was irradiated in dilute, oxygen-free, acetonitrile with 25ns flashes of 347.1 nm light. From transient photocurrent measurements it was inferred that ionic intermediates are formed.

There is as yet no consensus as to what effect insulin has on glucose uptake in the skeletal muscles of diabetic animals (Table 1). Different results have been reported from investigators whose animals were of different species, who used metabolic or non-metabolic glucose, or who worked with fed or fasted animals. We chose to work with mouse diaphragms. We used diaphragms of the KK-CAY mouse, genetically disposed to a syndrome similar to type 2 diabetes mellitus and including hyperglycemia, hyperinsulinemia, obesity and insulin resistance [12,13]. This species is compared with alloxan-diabetic and streptozotocin (STZ)-diabetic ddY mice in Table 2. Influence of diabetic state on insulin-induced 2-deoxyglucose or glucose uptake

The vinyl cation with a ethynyl fragment, C4H3+ is investigated with ab initio molecular orbital calculations. Two geometrical isomers of C4H3+, open chain and triangular geometries are calculated in order to ascertain the existence of the triangular isomer. The 4–31G* and MP3/6–31G*//4–31G* level calculations confirm that the latter is more stable than the former. However, the activation energy for intra-conversion is considered to be rather small. The calculated results are analyzed by comparing with experimental results. The relation between molecular vibration and reaction is analyzed by dynamic electron transfer.

Addition of alkoxide ions resulted in ipso substitution in the photolysis of an alcohol solution of 1-(p-methoxyphenyl)-2,2-diphenylvinyl bromide, whereas addition of triethylamine, pyridine, or NaHCO3 led to vinylic substitution.

An ipso adduct, vinylidenecyclohexadiene 2 , was isolated from the title photolysis and showed exclusive transformation to the corresponding vinyl ethers by alcoholysis.

Unilateral carotid endarterectomy was performed microsurgically in 60 rats. The effects of perioperative administration of aspirin and flunarizine, a Ca2+ entry blocker, on thrombus formation were examined 24 hours after endarterectomy. An untreated group of endarterectomized rats served as controls. Platelet adhesion, blood cells, and fibrin cords were observed at the cut edge of the intima as well as in the endarterectomized area in all three groups. However, these findings were significantly more extensive in the control group than in the drug-treated groups. Flunarizine was as effective as aspirin in inhibiting platelet adhesion and fibrin cord formation. Both drugs significantly increased the patency rate after carotid endarterectomy.

The reactions of 1-aryl-2,2-bis(o-methoxyphenyl)vinyl halides (4)–(7) in 80% aqueous ethanol (80% EtOH), acetic acid (AcOH), or 70% aqueous N,N-dimethylformamide gave benzofurans (8)–(10), respectively. The kinetic results i.e., 1) first-order reaction rates, 2) large α-substituent effect (ρ=−4.12 against σ+), 3) large leaving group effect (kBt⁄kCl=85 in 80% EtOH and 28 in AcOH) and 4) the solvent effect (m=0.53), are consistent with the formation of the intermediate vinyl cations (3) which are captured exclusively by the β-o-methoxyl group. In the reaction of vinyl bromide (7), the formation of 7–9% of benzofuran (11) results from the β-o-methoxyphenyl migration in the vinyl cation (17) followed by cyclization. The exclusive intramolecular cyclization of the vinyl cations is discussed in terms of the proximity effect of the β-o-methoxyl group.

The interaction of various cholecystokinin (CCK) peptides with the protein inhibitor (PK-I) of cyclic AMP dependent protein kinase (A-PK) has been studied. The order of the affinities ( ed 50 ) for relaxation of hog biliary muscle by a series of C -terminal peptides of CCK correlated with the order of the potencies for A-PK-catalyzed phosphorylation of the sarcoplasmic reticulum enriched fraction (SR-F) in the muscle. CCK-4 peptide inhibited the PK-I of A-PK. The apparent K m value of the peptide was 11.5 μM. Scatchard plot analysis for the binding of [ 14 C]CCK-6 peptide to the PK-I showed a dissociation constant ( K d ) of 11.2 μM. These results indicated that the K d value agreed with the ed 50 value of CCK-6 and the K m value of CCK-4. It is proposed that a receptor for CCK C -terminal peptides is probably a component in the PK-I; binding of the peptides to this site usually results in the relaxation by these allosteric inhibitors of the PK-I.

Irradiation of triarylchloroallenes in methanol afforded 1,3,3-triaryl-3-methoxypropynes, suggesting the intervention of triarylallenyl cations. Irradiation of triphenylchloroallene in ethanol and 2-propanol gave the similar results but the irradiation in t-butyl alcohol gave only the products from triphenylallenyl radical.

The mechanisms by which papaverine (Pap) relaxes smooth muscles of hog bile ducts were investigated with respect to the effects of Pap on the distribution of Ca ions in intracellular organelles. Muscles loaded with 45Ca ions in 139 mM KCl-Tyrode's solution were incubated with Pap, [3H]Pap or theophylline (ThP) in Tyrode's solution. The Pap and Ca contents of various subcellular fractions were measured. Pap (40 microM) had no effect on Ca influx into the muscle in normal and 139 mM KCl-Tyrode's solutions. Pap was distributed to a greater extent in the cytosol fraction (F4) than in microsome and mitochondria-enriched fractions (F3) and in the nuclei-enriched fraction (F2). Pap selectively accumulated in the plasma membrane-enriched fraction (PM-F) and was negligible in the sarcoplasmic reticulum-enriched fraction (SR-F) and the mitochondria-enriched fraction (Mit-F). The Ca release of PM-F was greater and more rapid than the release from SR-F or Mit-F. The increase in the content of Ca in PM-F induced by Pap was enhanced by oxalate, suggesting that the increase is based on the increase in Ca uptake, not on the reduced efflux. Pap increased dose-dependently the Ca content of PM-F and appeared to decrease the Ca contents of SR-F and Mit-F. ThP and cyclic AMP (4 microM) had no effect on the Ca uptake of PM-F and no influence on the effects of Pap. These results suggest that Pap relaxation of hog biliary smooth muscle results from the interaction of the drug with the plasma membrane causing cyclic AMP-independent sequestration of Ca.

Photolysis of 1,2-benzo-1,3-cycloalkadien-4-yl bromides and 1,2-benzo-,1,3-cycloalkadien-3-yl chlorides showed a remarkable effect of ring size on the rearrangements of the resulting 1,2-benzo-1,3-cycloalkadienyl cations, i.e., 1,2-aryl or alkyl migration across the double bond and 1,2-hydride or methyl migration to the cationic center.

Bromination reaction of o-arylthiophenyl-substituted ethylenes gave 1-aryl-1-benzothiophenium ions by intramolecular cyclization in the bromonium intermediates. The substituent and solvent effects are also discussed.

Irradiation of 2,2-di-p-, m-, and o-anisylvinyl bromides (1a–c) gave mainly p,p′-, m,m′-, and o,o′-dimethoxytolans (2a–c) respectively, by a 1,2-shift of the anisyl groups.

Photolysis of vinyl bromides with cyanate anion In a two-phase system gave only isoquinolinones as the N-site attacked products. However, the photolysis with thiocyanate anion gave both the N-site attacked products, isothioquinolinones or vinyl isothiocyanates, and the S-site attacked products, vinyl thiocyanates.

Both silver-assisted reaction of β-arylvinyl bromides and the photolysis in nitriles gave isoquinoline derivatives, indicating that the Ritter reaction involving a vinyl cation took place.

Photolysis of β-(o-aryloxyphenyl)vinyl bromides in methylene chloride as well as solvolysis in 60% EtOH gave dibenz[b,f]oxepins exclusively by a new type of intramolecular cyclization of vinyl cations.

The metal content of diaphragm, gastrocnemius, ventricle, and bladder muscles in genetically obese diabetic KK-CAy and alloxan-diabetic ddY mice was compared with that in prediabetic KK-CAy and normal ddY mice, because the muscles of the diabetic KK-CAy mice had morphological abnormalities, such as atrophy, disappearance of Z-band, disturbed myofibrils and swollen sarcoplasmic reticulum. The amounts of calcium (Ca) in gastrocnemius, ventricle and bladder muscles from the prediabetic KK-CAy mice were significantly 7.7, 98.3, and 36.9% greater, respectively, than those in normal ddY mice. In contrast, the magnesium (Mg) content of the diaphragm, the gastrocnemius, and the ventricle in the prediabetic mice was 8.6, 7.4, and 4.3% lower, respectively, than in the ddY mice. The iron (Fe) content of the diaphragm, gastrocnemius, and ventricle muscles in the prediabetic mice was 29.2, 43.6, and 44.6% greater, respectively, than in the ddY mice. The Ca content in the gastrocnemius muscles of the diabetic KK-CAy mice and the alloxan-diabetic mice was 19.8 and 11.7% higher, respectively, than in the prediabetic and normal mice. The Ca content of the ventricle muscle was increased only in the alloxan-mice. The gastrocnemius Mg was also 9.0 and 5.5% greater in the KK-CAy and the alloxan-mice. The Fe content of the diaphragm and the gastrocnemius muscles from the KK-CAy mice was 27.3 and 23.2% greater, respectively, than in the prediabetic mice. The zinc (Zn) content of the gastrocnemius and the bladder was 16.4 and 18.0% higher, but the ventricle Zn was 13.4% lower, respectively, than in the prediabetic control. The changes in metal content induced by the diabetic state may be related to the morphological abnormalities.

Photolysis of β-[(o-arylthio)phenyl]vinyl bromides, in contrast to the oxy-derivatives, resulted in exclusive cyclization at sulfur to give 1-benzothiophenes. The results were discussed by the nature of sulfur.

Publisher Summary Calcified tissues may be defined as exo- and endoskeletons formed both at specific sites and at pathologically induced sites in organisms. These tissues are of either epithelial or mesenchymal origin. Despite the extensive studies on the role of AMPS's and PP complexes in many different calcified tissues, it is not possible at present to state conclusively whether or not AMPS's are actually necessary for biological calcification. It has been generally accepted that matrix formation precedes the onset of calcification. Mineral ions in calcifying solution are deposited and crystallized in vitro even on the surface of inert solid substances such as film and glass; however, if only spaces or lattices available for mineral deposition are present, mineralization may occur. Biologically, however, it may be reasonable that all or most tissues are calcifiable, but some inhibitory factors necessary for their mineralization. Chemically, the presence of both microheterogeneity and polymorphism in CS chains has been increasingly observed. Consequently, a description of the real role of the AMPS'S in biological calcification must await future studies.

Irradiation of both 1,1-diphenyl-2-bromopropene(1a) and -ethylene (1b) in methanol in the presence of copper(II) salt resulted in the great increase of the yield of ionic products when compared to that without the salt. This suggests that cupric salt reacts with the vinyl radical, which is escaped from the solvent cage, to give ionic species via vinylcopper intermediate (8).

Irradiation of triarylchloroallenes in methanol afforded 1,3,3-triaryl-3-methoxypropynes, suggesting the intervention of triarylallenyl cations. Irradiation of triphenylchloroallene in ethanol and 2-propanol gave the similar results but the irradiation in t-butyl alcohol gave only the products from triphenylallenyl radical.

Solvolytic reactions of triarylchloroallenes in the presence of thiocyanate and O-ethyl dithiocarbonate anions gave the corresponding allenyl derivatives, while the reaction in the presence of cyanate anion afforded the corresponding propargyl derivative. These results are interpreted in terms of a steric factor of the nucleophiles.

Treatment of o-(phenyloxy)phenylalkyne 1 with HClO4 or HBF4 gave dibenz(b, f)oxepin 2, whereas the sulfur analogue, o-(phenylthio)phenylalkyne 3, provided 1-phenyl-1-benzothiophenium salts 4.

A 1,4-dioxaspiro[4.5]deca-6,9-diene was obtained in high yield by photolysis of 1-bromo-1-[p-(2-hydroxy-2-methylpropoxy)phenyl]-2,2-diphenylethene in the presence of sodium 2-propoxide.

Introduction of a substituent into ortho-position of β-aryl group in a vinyl bromide resulted in the preferential formation of a vinyl cation in the photolysis. It is considered that the steric repulsion of β-aryl groups makes a convenient conformation for an electron transfer from the aromatic ring to the halogen atom in the radical pair.

Solvolysis of 2-bromobut-1-en-3-yne (2) and 1-halogenobuta-1,2,3-trienes (3) shows that incorporation of a triple bond in an α-aryl-stabilized vinyl cation system destabilizes the cation owing to a larger inductive effect of the triple bond compared with its π-conjugative effect and that the difference in rates of reaction of (2) and (3a) can be ascribed to a difference in their ground-state energies.

Photolysis of β-(o-aryloxyphenyl)vinyl bromides in methylene chloride as well as solvolysis in 60% EtOH gave dibenz[b,f]oxepins exclusively by a new type of intramolecular cyclization of vinyl cations.

An ipso adduct, vinylidenecyclohexadiene 2 , was isolated from the title photolysis and showed exclusive transformation to the corresponding vinyl ethers by alcoholysis.

The exclusive formation of 3-(p-hydroxyphenyl)-2-phenylbenzofuran from the solvolysis of both 2-(p-acetoxyphenyl)-2-(o-methoxyphenyl)-1-and 2-(p-acetoxyphenyl)-1-(o-methoxyphenyl)-2-phenyl vinyl bromide and the formation of a 1:1 mixture of 3-(p-hydroxyphenyl)-2-(o-methoxyphenyl)- and 2-(o-ethoxyphenyl)-3-(p-hydroxyphenyl)-benzofuran from 2-(p-acetoxyphenyl)-2-(o-ethoxyphenyl)-1-(o-methoxyphenyl)vinyl bromide under alkaline conditions provide firm evidence for the presence of the title compound as the precursor of benzofurans of this type.