Research on the influence of variations in environmental temperatures on the systemic effects of alcohol alone and in combination with other drugs

SummaryADP, AMP, or ATP was injected rapidly intravenously in rats. ADP injection resulted in the f olio wing transient changes: a drop in platelet count, a rise in central venous pressure, a fall in carotid arterial PO2, bradycardia, arrhythmia, flutter-fibrillation, and arterial hypotension. AMP and ATP produced some of these same effects; but except for hypotension, their frequency and severity Avere much less than those following ADP.Prior intravenous administration of acetylsalicylic acid or pyridinolcarbamate, two inhibitors of the second wave of ADP-induced platelet aggregation in vitro, significantly reduced the frequency and severity of all the above ADP-induced changes except hypotension. These observations suggest that many of the changes (except hypotension) observed to follow ADP injection are produced by platelet aggregates which lodge transiently in various microcirculatory beds then rapidly disaggregate and recirculate.

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Dealing with hot rocky environments: Critical thermal maxima and locomotor performance in Leptodactylus lithonaetes (Anura: Leptodactylidae)

Herpetological Journal ◽

10.33256/hj29.3.155161 ◽

2019 ◽

pp. 155-161 ◽

Cited By ~ 1

Author(s):

Ivan Beltran

Keyword(s):

Environmental Temperature ◽

Extreme Temperature ◽

Effect Of Temperature ◽

Maximum Speed ◽

Locomotor Performance ◽

Extreme Temperatures ◽

Physiological Limits ◽

Fitness Consequences ◽

Thermal Maximum ◽

Environmental Temperatures

Environmental temperature has fitness consequences on ectotherm development, ecology and behaviour. Amphibians are especially vulnerable because thermoregulation often trades with appropriate water balance. Although substantial research has evaluated the effect of temperature in amphibian locomotion and physiological limits, there is little information about amphibians living under extreme temperature conditions. Leptodactylus lithonaetes is a frog allegedly specialised to forage and breed on dark granitic outcrops and associated puddles, which reach environmental temperatures well above 40 ˚C. Adults can select thermally favourable microhabitats during the day while tadpoles are constrained to rock puddles and associated temperature fluctuations; we thus established microhabitat temperatures and tested whether the critical thermal maximum (CTmax) of L. lithonaetes is higher in tadpoles compared to adults. In addition, we evaluated the effect of water temperature on locomotor performance of tadpoles. Contrary to our expectations, puddle temperatures were comparable and even lower than those temperatures measured in the microhabitats used by adults in the daytime. Nonetheless, the CTmax was 42.3 ˚C for tadpoles and 39.7 ˚C for adults. Regarding locomotor performance, maximum speed and maximum distance travelled by tadpoles peaked around 34 ˚C, approximately 1 ˚C below the maximum puddle temperatures registered in the puddles. In conclusion, L. lithonaetes tadpoles have a higher CTmax compared to adults, suggesting a longer exposure to extreme temperatures that lead to maintain their physiological performance at high temperatures. We suggest that these conditions are adaptations to face the strong selection forces driven by this granitic habitat.

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GENERAL EFFECTS OF α-MELANOCYTE STIMULATING HORMONE IN THE RABBIT

Acta Endocrinologica ◽

10.1530/acta.0.0480609 ◽

1965 ◽

Vol 48 (4) ◽

pp. 609-618 ◽

Cited By ~ 11

Author(s):

H. K. Dyster-Aas ◽

C. E. T. Krakau

Keyword(s):

Fatty Acids ◽

Free Fatty Acids ◽

Serum Calcium ◽

Calcium Level ◽

Serum Calcium Level ◽

Systemic Effects ◽

List Type ◽

Aqueous Flare ◽

Melanocyte Stimulating Hormone ◽

Blood Aqueous Barrier

ABSTRACT In addition to the previously described permeability disturbance in the blood aqueous barrier of the eye, measured as an increase of the aqueous flare, a series of transitory systemic effects have been recorded following the subcutaneous injection of synthetic α-MSH: marked increase of the free fatty acids in plasma, decrease in the serum calcium level, decrease in the blood pressure, increase in the skin temperature, increased frequency and diminished amplitude of respiration, presence of slow waves in the EEG. There is a correlation between the magnitude of the aqueous flare increase and the increase of free fatty acids in plasma and also between the aqueous flare and the minimum serum calcium level.

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