PubMed Health⌕ Search

Biomedical subjects

S Kozłowski

Publications and source records attributed to S Kozłowski.

At least 37 records · Page 2Linked to original sources
PubMed1982

Changes in muscle lipoprotein lipase activity during exercise in dogs fed on a mixed fat-rich meal.

Skeletal muscle lipoprotein lipase activity LPLA was compared in dogs performing prolonged treadmill exercise after 20-22 h fasting or 4 h following mixed fat-rich meal ingestion. In the fasting state muscle LPLA increased progressively during 2 h exercise. In fed dogs the resting value of the muscle LPLA was considerably lower than that in the fasting state, and no increase in the enzyme activity occurred during physical effort. The inhibition of the muscle LPLA by the meal ingestion can be attributed to the persisting effects of increased plasma insulin and/or FFA concentrations, found at the beginning of exercise.

Animals↗
PubMed1980

Extracellular hyperosmolality and body temperature during physical exercise in dogs.

The purpose of this study was to test the hypothesis that thermoregulation during exercise can be affected by extracellular fluid hyperosmolality [Osm] without changing the plasma Na+ concentration. The effects of preexercise venous infusions of hypertonic mannitol and NaCl solutions on rectal temperature (Tre) responses were compared in dogs running at moderate intensity for 60 min on a treadmill. Plasma E1Na+] was increased by 12 meq/l (P less than 0.05) after NaCl infusion, and decreased by 9 meq/l (P less than 0.05) after mannitol infusion. Both infusions increased plasma [Osm] by 15 mosmol/kg (P less than 0.05). After both infusions, Tre was essentially constant during 60 min rest. However, compared with the noninfusion exercise increase in Tre of 1.3 degrees C, Tre increased by 1.9 degrees C (delta delta Tre = 0.5 degrees C, P less than 0.05) after both postinfusion exercise experiments. It was concluded that inducing extracellular hyperosmolality, without elevating plasma [Na+], can induce excessive increases in Tre during exercise but not at rest.

Animals↗
PubMed1979

ADH and thermal sweating.

Sweating responses to heat exposure were compared in healthy subjects pretreated with pitressin or alcohol and in the control group. Between the three groups, there were no consistent differences in the rate of sweating expressed both as a total body weight loss during 2-h heat exposure and in mg of sweat per skin area covered by a paper disc. Likewise, there were no differences in the sweat osmolality or electrolyte concentration. There was also no evidence of inverse correlation between plasma ADH level and rate of sweat secretion or its concentration when pooled data of all subjects were analyzed. It was concluded that ADH did not substantially affect thermal sweating in men.

Adult↗
PubMed1979

Lipoprotein lipase activity in the skeletal muscle during physical exercise in dogs.

Changes in lipoprotein lipase activity /LPLA/ in the quadriceps femoris muscle were followed in ten dogs during 3-hour treadmill exercise and 2-hour post-exercise recovery period. During the first hour of exercise muscle LPLA steeply increased. Subsequently the enzyme activity tended to plateau. After exercise LPLA decreased to the pre-exercise value within 1 hour. It is concluded that exercise increases the ability of skeletal muscles to remove triglycerides from the circulation.

Animals↗
PubMed1979

Thirst and renal excretion of water and electrolytes during pyrogen fever in dogs.

Body temperature, water intake, urine output, sodium and potassium excretion, osmolal and free water clearance, plasma osmolality, sodium and potassium concentrations and osmotic thirst were examined in conscious dogs during pyrogen fever and compared to those found under control conditions. Arterial blood pressure and central venous pressure were also measured in some experiments. Administration of pyrogen produced transient but significant decreases in urine output and striking increases in the spontaneous water intake in some of the experiments in the phase of increasing fever. Arterial blood pressure decreased, whetreas central venous pressure increased at this stage of fever. No significant changes in renal excretion of solutes and free water as well as sodium and potassium were found. Plasma osmolality and sodium concentration increased and potassium concentration decreased unsignificantly both in control and pyrogen experiments. The main finding was that the thirst threshold to osmotic stimuli increased markedly during the phase of stabilized fever may be caused by significant increase in internal body temperature.

Animals↗
PubMed1975

Equipotency of hypertonic solutions of mannitol and sodium chloride in eliciting thirst in the dog.

The dogs were infused intravenously with either 3.6% NaCl or 20% mannitol solutions. Both infusions stimulated the animals to drink water when similar osmotic loads were introduced and exactly the same degree of cellular dehydration achieved. The amounts of water drunk at thirst threshold did not differ significantly. The results are discussed with relation to the hypothesis of osmometric control of water intake.

Animals↗
PubMedDate not supplied

Thirst impairment elicited by intraventricular administration of vasopressin antagonists.

To determine whether centrally released vasopressin influences thirst, observations of osmotic thirst threshold, osmotic load excretion and postloading restitution of plasma osmolality were made in dogs in control experiments and during infusion of AVP antagonists into the third ventricle. Significant elevation of osmotic thirst threshold was elicited by infusion of d(CH2)5AVP at a rate of 0.2-2.0 micrograms.min-1 and of d(Et2)AVP at a rate of 0.3 micrograms.min-1 (V1 antagonists, weak V2 agonists) as well as by administration of d(CH2)5[D-Ile2,Abu4]AVP at a rate of 0.4 micrograms.min-1 (potent V2 antagonist, weak V1 antagonist). Administration of d(CH2)5AVP at a rate of 2.0 micrograms.min-1 was associated with a significant suppression of the postloading water intake and osmotic load excretion and with a delay in restitution of plasma osmolality. These findings indicate that centrally released vasopressin may participate in the control of thirst.

Animals↗
PubMedDate not supplied

Prolonged hyperadrenalinemia impairs exercise ability in rats.

This study was performed on rats with sustained (24 h) hyperadrenalinemia produced by sc implantation of retard adrenaline (A) tablets. Comparing with control, sham-operated animals, in A-treated rats duration of endurance exercise until exhaustion was shortened by approx. 40%. This was accompanied by: significant decreases of the pre-exercise muscle glycogen and creatine phosphate values in both "slow twitching" (soleus) and "fast twitching" (white portion of gastrocnemius) muscles, and of ATP content in soleus. Muscle lactate and pyruvate contents as well as blood glucose and FFA levels were elevated. After exercise muscle substrate and metabolite contents were similar in both groups in spite of the difference in exercise duration. It is concluded that prolonged hyperadrenalinemia diminishes the intramuscular energy substrate content, thereby reducing endurance capacity of rats.

Animals↗
PubMedDate not supplied

Progressive enhancement of body temperature responses to consecutive exercise-bouts of the same intensity in dogs.

Progressive enhancement of body temperature responses to consecutive exercise-bouts of the same intensity in dogs. Acta physiol. pol., 1985, 36 (3): 165-174. Changes in rectal (Tre), muscle (Tm), and hypothalamic (Thy) temperatures, plasma osmolality, and some intermediary metabolic variables were examined in dogs performing four successive exercise-bouts of the same intensity. During the rest-intervals separating the exercise-bouts body temperatures returned to initial levels and water losses were replaced. Tm and Tre responses to consecutive exercise-bouts were progressively increasing. Similar tendency was found in Thy changes. Cardiac and respiratory frequencies attained the same levels in all four exercise-bouts, while blood lactate and FFA concentrations were increasing and blood glucose level was decreasing progressively. No changes in plasma osmolality was noted. Exercise-induced increases in Tm correlated positively with plasma FFA concentration (r = 0.68). Body temperature responses to exercise were reduced by beta-adrenergic blockade. It is concluded that the enhancement of the thermal responses to consecutive exercise-bouts can be related to the metabolic action of catecholamines.

Animals↗