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B Dabrowski

Publications and source records attributed to B Dabrowski.

At least 55 records · Page 3Linked to original sources
PubMed1989

Effect of hindlimb immobilization and recovery on compensatory hypertrophied rat plantaris muscle.

Compensatory hypertrophy of the rat plantaris muscle (PLT) was induced by ipsilateral gastrocnemius muscle ablation. Following 8 weeks (wks) of hypertrophy, hindlimbs were cast immobilized (HI) for 4 weeks after which weight bearing was unrestricted for 8 wks (recovery). Compensatory hypertrophy increased PLT wet weight/body weight ratio (83%), muscle fiber cross-sectional areas (1.5 to 2 fold), and the percent of slow oxidative (%SO) fibers (2 fold) in the experimental compared to the contralateral sham control muscle. PLT protein content and maximal activities of phosphofructokinase (PFK), mitochondrial glycerol phosphate dehydrogenase, and succinate dehydrogenase were unaltered with muscle hypertrophy. HI produced significant decreases in PFK activity (50%) and muscle fiber cross-sectional areas (50%) but did not significantly change the histochemical myofibrillar ATPase profile. Following remobilization, muscle weight/body weight ratio and maximal enzyme activities recovered to that of aged matched controls. Muscle fiber areas returned to pre-immobilization sizes but were approximately 25% smaller than aged matched control hypertrophy muscles. The %SO fibers in the hypertrophied muscle remained higher than controls but did not return to pre-immobilization values. These results indicate that biochemical and histochemical characteristics of hypertrophied rat PLT recover from HI during 8 wks of normal weight bearing similar to that of normal control muscle. However, the recovery time period was insufficient to allow complete compensation of fiber size to that of the age-matched control animals.

Animals↗
PubMed1988

Postmortem biochemical indices of antemortem hemorrhagic shock.

The purpose of this study was to determine if the perturbations in two glycolytic metabolites that occur during hemorrhagic shock can be used as discriminatory postmortem indicators of death resulting from severe hemorrhagic shock. Two groups of male albino Sprague-Dawley rats were hemorrhaged by withdrawing either 40% (Group I) or 45% (Group II) of the total blood volume. Glycogen and lactate concentrations were determined at 0 and 48 hr postmortem in the following tissues and organs: diaphragm, heart, liver, kidney cortex, and kidney medulla. The differences in lactate and glycogen in Group I at 0 hr were not significantly different from the nonhemorrhaged controls, with the exception of the lower liver glycogen concentration (58% of control). In Group II glycogen concentration was significantly reduced at 0 hr in the diaphragm (70% of control), liver (37%), and kidney medulla (55%). Lactate concentration was higher in all tissues examined by 270-640%; within 48 hr all tissues for both control and hemorrhaged animals had declined to baseline levels of glycogen concentration, whereas lactate levels had increased as much as 34-fold. There were no highly significant differences in glycogen at 48 hr between the control and hemorrhaged groups. In Group II the lactates were similar for both the control and hemorrhaged animals with the exception of the higher concentrations in the kidney cortex (54%) and medulla (41%). It was concluded from these findings that although significant metabolic perturbations are present at the time of death due to hemorrhage these differences do not persist up to 48 hr postmortem, with the possible exception of the kidney lactate concentrations.

Animals↗
PubMed1987

Na+/K+-ATPase activity of different types of striated muscles.

Na+/K+-ATPase activity was determined in striated muscles with different aerobic capacities. The underlying hypothesis was that different aerobic capacities are reflective of different contractile activity which imposes greater demands on sarcolemmal ion translocation and may thus set Na pumping capacity. The added ion translocation demands required during exercise-training on Na+/K+-ATPase activity in different muscle fiber types may require an adaptation of this enzyme. The highest and lowest Na+/K+-ATPase activity was in the heart and white gastrocnemius muscle (WG), respectively. A high linear correlation existed between Na+/K+-ATPase activity and succinate dehydrogenase activity in the six muscles studied. Exercise-training did not increase Na+/K+-ATPase activity in any of the muscles, but did increase the aerobic capacity, except in the heart and WG. It was concluded that Na+/K+-ATPase activity has a high positive correlation with the aerobic capacity of striated muscles in the rat and that the Na pump capacity does not adapt to exercise-training of 1 hr X day-1 as does aerobic capacity.

Aerobiosis↗