The effect of prolonged administration of alcohol on calcium binding and uptake by sarcoplasmic reticulum and mitochondria and on respiratory function of mitochondria was investigated in heart muscle of dogs. Dogs were paired and maintained with and without alcohol for 6 months; alcohol was administered by adding it to drinking water and food with vitamin supplements. Measurements were made after alcohol had been temporarily withheld for 2 days. Prolonged alcohol ingestion resulted in a decline in calcium binding and uptake by sarcoplasmic reticulum and mitochondria, suggesting a diminished affinity of the reticular and mitochondrial membranes for calcium ions. The endogenous calcium content of mitochondria and sarcoplasmic reticulum decreased. Prolonged alcohol administration failed to alter cardiac contractility, although contraction and relaxation tended to diminish following the administration of angiotensin. The results illustrate that one link in the regulation of the state of contraction or relaxation involving myofibrillar calcium transport is weakened in dogs maintained on alcohol for prolonged periods of time. KEY WORDScalcium binding and uptake mitochondrial respiration sarcoplasmic reticulum alcohol and cardiac contractility excitation-contraction coupling
CHARACTERIZATION OF TRIMETHPLSILYLCYCLOHEXANOLS2483 exo-7-Acetoxy 1,6-dimethylbicyclo [4.1 .O]heptane.'8--To a solution of 5.0 g (29.8 mmoles) of exo acid, mp 137-139', in 100mlof anhydrous ether, was added with stirring 160 ml of a solution of methyllithium in ether containing 59.6 mmoles of total base as l?termined by titration. After 5 min the reaction mixture was worked up, yielding 1.75 g of recovered starting material, mp 136-139", and 3.34 g of neutral product. The small amount of less volatile tertiary alcohol (2.87 p ) cont,aminating the product was removed by distillation through a spinning-band column at oil pump pressure which gavc 2.08 g of ketone (65% based on unrecovered acid): bp 29-30' (0.2 mm); 5.92 p ;210 mp ( E 6800); I (CC1.t) 7.89 (3 H) and 8.80 (6 H).To a slurry of 2.00 g (12.0 mmoles) of ketone and t 6 g of dibasic sodium phosphate in 80 ml of methylene chloride was added, with stirring, a solut,ion of peroxytrifluoroacetic acid prepared by adding, with stirring, 1.0 ml (37 mmoles) of 90% hydrogen peroxide and 6.2 ml (44 mmoles) of trifluoroacetic anhydride to 15 ml of ice-cooled methylene chloride. Work-up gave 1.50 g of crude product which was first subjected to shortpath dist,illation (oil bath 105-140") and then preparative gc. Material corresponding to the major peak (85%) at 6.7 rnin was collected: A tz 5.73 p ; I (CClr) 6.42 (1 H) 8.00 (3 H), 9.03 ( 6 H). A n d . Calcd for CI1HlnO2: C, 72.53; H, 9.89. Found: C, 72.76; H, 10.07.Conversion of the cyclopropyl acetate to cyclopropanol was effected by using freshly dist,illed solvents for each run (including work lip). Typically, a solution of 37 mg of acetate in a mixture of 2.5 ml of methanol and 1.5 ml of 0.3 N sodium hydroxide sohition was allowed to st and at room temperature for 50 miri under nitrogen. Water (10 ml) was then added and the mixture was extracted with three 3-ml portions of pentane. The combined extracts were washed with 2 ml of water and then dried over sodinm snlfate. Evaporation of solvent left a white solid showing hydroxylir (2.8 and 2.9 p ) but no carbonyl absorp tion; 7 (CDCI,) 6.93 (1 H), 8.07 ( 1 H), 8.95 (1 HI singlet superimposed on complex absorption).The white solid from one run was treated with excess acetic anhydride in pyridine. Work-up, nsing carbon tetrachloride as solvent, gave a solution showing the same nmr absorption as (18) General procsedures: G. Tegner, Acta Chem. S c a d . , 6, 782 (1952); K, D. Emmons and G. 13. Lneas, J. Am. Chem. Sac., 77, 2287 (1955); C. H. DePuy and L. R. Slahoney, {bid., 86, 2653 (1964).starting acetate. Capillary gc of the concentrated solution showed, apart from solvent, only one peak with a retention time corresponding to that of starting acet,ate. endo-7-Acetoxy-l,6-dimethylbicyclo[4.1 .O] heptane was similarly prepared18 from endo acid, mp 120-122"; 1.450 g of the acid yielding 0.800 g of crude ketone which showed only weak hydroxyl absorption in the infrared spectrum. A portion (580 mg) of this crude ketone was subjected to Baeyer-Villiger oxidation, giving 549 mg...
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