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Biomedical subjects

A M Konecka

Publications and source records attributed to A M Konecka.

At least 19 recordsLinked to original sources
PubMed1998

Circadian rhythm of pain in male mice.

1. Circadian rhythm of pain in response to the thermal stimuli was assessed in male mice. 2. The hot-plate method was used. Response latencies were measured every 2 hours and showed a sinusoidal rhythm. 3. Minimal latencies were observed at 10 and 20 h, the highest were obtained at 12 and 4 hours. 4. The circadian changes in pain sensitivity may play an important role in many experiments on stress and post-stress analgesia as well as on susceptibility to pharmacological agents.

Animals↗
PubMed1997

Effect of cholesterol-enriched diet on liver and heart enzymes in male rabbits.

White New Zealand male rabbits were fed a high-cholesterol (1%) diet for 7 weeks. The activity of alkaline phosphatase (AP), alanine (AlaAT), aspartate (AspAT) aminotransferases and level of glucose in the blood plasma of rabbits was determined and compared with those of a control group of animals. The cholesterol-enriched diet resulted in increases in plasma AlaAT and AP activity and a decrease in plasma glucose. In the liver, cholesterol treatment decreased the activity of AspAT, AlaAT, AP, phosphoglucomutase, phosphofructokinase, pyruvate kinase and lactate dehydrogenase. Activities of glucosephosphate isomerase, aldolase and the level of glycogen were not affected. No statistically significant changes in the activity of examined enzymes in heart of rabbits fed with cholesterol-enriched diet were observed. Chronic intake of cholesterol in the diet had a negative effect on liver metabolism but not on heart metabolism in rabbits.

Alanine Transaminase↗
PubMed1990

Stressors and pain sensitivity in CFW mice. Role of opioid peptides.

Effects of several environmental situations on pain threshold were studied in CFW male mice. Immobilization induced significant and naloxone reversible analgesia. Isolation produced analgesia which was partially reversed by naloxone. One minute swimming in + 4 degrees C or + 42 degrees C water increased naloxone reversible analgesia. Isolation produced analgesia which was partially reversed by naloxone. One minute swimming in 4 degrees C or + 42 degrees C water increased naloxone irreversible pain threshold. Other situations: drinking 2% NaCl solution, disturbance of light-dark cycle or social aggregation did not produce analgesia. The role of these situations as stress-inducers, as well as the role of endogenous opioid peptides in stress-induced analgesia, were discussed.

Animals↗
PubMed1987

Bivalent opioid peptide analogues with reduced distances between pharmacophores.

To investigate the role of distance between two opioid peptide pharmacophores on in vitro and in vivo activities, three new bivalent opioid analogues have been synthesized in which the dipeptide Tyr-D-Phe was connected with diamine moieties ("bridges"). The analogue with a hydrazine bridge has high receptor affinity to mu, kappa, and delta receptor types, as well as potent and long acting antinociceptive activity after intraperitoneal administration.

Animals↗
PubMed1985

Spontaneously prolonged dioestrus and serotonin in various regions of the rat brain.

5-Hydroxytryptamine (serotonin, 5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) concentrations were investigated in various regions of the brain on the day of normal and spontaneously prolonged dioestrus in the rat. The 5-HT/5-HIAA concentration ratio and 5-HT content were found to be higher in the medial-basal hypothalamus (MBH) and the fronto-parietal cerebral cortex (Bc), and lower in the preoptic-anterior hypothalamic area (PAHA), when dioestrus was prolonged. No significant difference was observed with 5-HT and 5-HIAA concentrations in the hippocampus (Hipp). It was concluded that there are significant alterations in 5-HT activity in the MBH, PAHA and the Bc when dioestrus is spontaneously prolonged.

Animals↗
PubMed1985

The effect of food and water deprivation on post-stress analgesia in mice and levels of beta-endorphin and dynorphin in blood plasma and hypothalamus.

Pain sensitivity of food and/or water-deprived male mice was tested on a hotplate. The most pronounced analgesia ensued in animals given no food and water, and no food but water ad libitum, the least one in water-deprived mice. The magnitude of the rise in pain threshold depended on the duration of deprivation and was correlated with the increase in the blood plasma beta-endorphin level. In the hypothalamus beta-endorphin level increased after 72-h food deprivation only. The level of dynorphin remained unchanged. Naloxone (10 mg/kg) almost completely reversed food or water-deprivation induced analgesia.

Analgesia↗
PubMed1984

Suppression of food and water intake after intracerebroventricular infusion of morphine and naloxone in rabbits.

The effect of intracerebroventricular infusion of morphine and naloxone on food and water intake was investigated in rabbits. Morphine hydrochloride at a dose of 120, 10 and 5 micrograms produced statistically significant suppression of 24-h food and water intake. The same effect ensued after infusion of naloxone at dose of 120 and 10 micrograms. Postmorphine aphagia was accompanied by a rise in blood free fatty acids and normal glucose levels. No changes were seen after naloxone.

Animals↗
PubMed1983

The opioid peptide dynorphin, circadian rhythms, and starvation.

Dynorphin, an opioid peptide whose functions are unknown, is found in brain, pituitary, and peripheral organs. Specific radioimmunoassays were used to measure dynorphin in the hypothalamus and pituitary, during the day and at night, as a function of food and water deprivation. Immunoreactive dynorphin was increased in the hypothalamus and decreased in the pituitary at night. Water deprivation led to more than 50 percent reduction in daytime levels of pituitary dynorphin and concomitant increases in hypothalamic dynorphin.

Animals↗
PubMed1983

The effect of repeated administration of L-thyroxine on the activity of certain enzymes in the blood plasma of hens.

Studies on the influence of long-lasting hyperthyroidism on enzyme activities and total protein level in the blood plasma of adult Leghorn hens showed that: 1. Protein level during whole experimental period showed inconsiderable variability irrespective of T4 dose. 2. Activity of aspartate aminotransferase (GOT) and alanine aminotransferase (GPT) increased. Changes were dependent on T4 dosage level. 3. T4 had no effect on activity of aldolase.

Alanine Transaminase↗
PubMed1982

Effect of L-thyroxine on metabolism in Japanese quails (Cotournix cotournix japonica)--II. Activity of GOT and GPT in liver, LDH and ICDH in heart and kidney after multiple injections of L-thyroxine.

1. Quails hatched from eggs incubated at physiological temperature (37.5 degrees C--normal quails) and elevated (39.3 degrees C--warm quails) were injected with L-thyroxine (T4) at the dose of 600 micrograms/kg of body weight, every 48 hr for 17 days. 2. Twenty-four hours after the last injection activity of aspartate aminotransferase (GOT), alanine aminotransferase (GPT) was determined in liver homogenates and lactate dehydrogenase and isocitrate dehydrogenase in homogenates of heart and kidney. 3. Significant increase of the activity of GPT in liver homogenates was observed in normal and warm quails up to 252.9 and 186.8% of control, respectively). 4. The activity of aspartate aminotransferase increased significantly in liver homogenates of T4-treated normal quails, while such changes in the warm quails were not observed. 5. Activities of lactate dehydrogenase (LDH) and isocitrate dehydrogenase (ICDH) in heart and kidney homogenates in both T4-treated groups of birds did not change.

Alanine Transaminase↗
PubMed1982

The effect of intracerebroventricular infusion of morphine, methionine-enkephalin and D-Ala2-enkephalinamide on body temperature of rabbits.

The effect of intracerebroventricular infusions of two synthetically obtained peptides: Met-enkephalin hydrochloride and D-Ala2-Met-enkephalinamide hydrochloride, and of morphine hydrochloride on rectal temperature was investigated in conscious rabbits. Morphine hydrochloride in a dose of 240 micrograms and D-Ala2-Met-enkephalinamide hydrochloride in doses of 240 and 3000 micrograms produced a hyperthermia which was accompanied by ear vasoconstriction and shivering. No such effect ensued after Met-enkephalin, possibly due to rapid enzymatic degradation of this compound. The concept of opioid involvement in the central thermoregulatory mechanism is discussed.

Animals↗
PubMed1982

Double enkephalins.

Basing on the conclusions drawn from the biological activities of previously synthesized enkephalin analogues, a new class of enkephalin analogues named double-enkephalins have been proposed, in which C-terminal amino acid residue is replaced by a second active fragment of enkephalin analogue connected by diamine bridge. Guinea-pig ileum test showed high biological activity of proposed analogues but depending on the size of diamine bridges.

Animals↗