Does Prenatal Methamphetamine Exposure Induce Cross-sensitization to Cocaine and Morphine in Adult Male Rats? 190)

R e c e i ve d J a n u a r y 2 3 , 2 0 12 ; A c c e p t e d Ju n e 2 5 , 2 0 1 2 . Key words: Prenatal drug exposure -Methamphetamine -Cocaine -MorphineOpen field -Plantar test -Conditioned place preference -LocomotionNociception -Drug-seeking behavior Abstract: The aim of the present study was to examine the cross-sensitization induced by prenatal methamphetamine (MA) exposure to challenge dose of cocaine or morphine. Rat mothers received a daily injection of MA (5 mg/kg) or saline throughout the gestation period. Adult male offspring (prenatally MA-or saline-exposed) were divided to groups with challenge doses of saline (1 ml/kg), cocaine (5 mg/kg) or morphine (5 mg/kg). Behavior in unknown environment was examined in Laboras, nociception in Plantar test, and active drug-seeking behavior in conditioned place preference (CPP). Our data demonstrate that cocaine increased the exploratory activity in Laboras test in prenatally saline-exposed, but decreased it in prenatally MA-exposed rats. An analgesic effect of cocaine was demonstrated only by the tail withdrawal and it was independent of the prenatal drug exposure. CPP test showed that prenatal MA exposure induced rather tolerance than sensitization to cocaine. In contrast to cocaine effects, morphine decreased rearing activity in both, prenatally MA-exposed and saline-exposed rats, and locomotion only in prenatally MA-exposed rats in the Laboras. In the Plantar Prague Medical Report / Vol. 113 (2012) No. 3, p. 189-205 test, the results demonstrated that morphine had an analgesic effect in prenatally saline-exposed rats but this effect was suppressed in prenatally MA-exposed rats. In the CPP test morphine induced drug-seeking behavior, which however was not affected by prenatal drug exposure. Thus, our data demonstrate that there is a cross-effect between prenatal MA exposure and the challenge dose of other drug in adulthood, however drug-seeking behavior is not increased by prenatal MA exposure as we expected

Objective Evaluation of Chronic Low-Back Pain Using Serum Lipids: The Role of the Doctor-Patient Relationship

Statistical data show that pain intensity in patients with low back pain is associated with a higher BMI, total serum cholesterol, and triacylglycerol levels. The objective of our study was to evaluate how these associations are dependent on the nature of the patient-doctor relationship. Eighty-nine patients hospitalized with chronic low-back pain (50 women, 39 men; average age: 64.5 ± 12.7 years) were assessed over a 3-year period. A serum lipid analysis was conducted (LDL-C, HDL-C, and total cholesterols) at admission in parallel with a subjective evaluation of pain intensity, which was assessed using a numeric rating scale. The participating physician assigned, based on their personal interaction with the patient, an attribute of affinity (positive, neutral, and negative) towards them. Current serum lipid levels and pain intensity were correlated relative to these attributes. Pain intensity did not differ between the groups assigned positive or negative attributes of affinity. In patients belonging to the “positive” group, pain intensity correlated positively with total cholesterol (p=0.01) and LDL cholesterol (p=0.007). No correlations were found in the “negative” group or when the patient-doctor relationship was ignored. We found a significant association between subjectively assessed low back pain intensity and serum levels of total and LDL cholesterol in patients with whom the physician had a positive affinity. A positive affinity with the patients having chronic pain and the patient’s trust in their physicians may ultimately mean that the patient’s statement about pain is more credible, which may retroactively affect the outcome of therapy

Can Anxiety Tested in the Elevated Plus-maze Be Related to Nociception Sensitivity in Adult Male Rats?

Methamphetamine (MA) is one of the most addictive psychostimulant drugs with a high potential for abuse. Our previous studies demonstrated that MA administered to pregnant rats increases pain sensitivity and anxiety in their adult offspring and makes them more sensitive to acute administration of the same drug in adulthood. Because individuals can differ considerably in terms of behaviour and physiology, such as rats that do not belong in some characteristics (e.g. anxiety) to average, can be described as low-responders or high-responders, are then more or less sensitive to pain. Therefore, prenatally MA-exposed adult male rats treated in adulthood with a single dose of MA (1 mg/ml/kg) or saline (1 ml/kg) were tested in the present study. We examined the effect of acute MA treatment on: (1) the anxiety in the Elevated plus-maze (EPM) test and memory in EPM re-test; (2) nociception sensitivity in the Plantar test; (3) the correlation between the anxiety, memory and the nociception. Our results demonstrate that: (1) MA has an anxiogenic effect on animals prenatally exposed to the same drug in the EPM; (2) all the differences induced by acute MA treatment disappeared within the time of 48 hours; (3) there was no effect of MA on nociception per se, but MA induced higher anxiety in individuals less sensitive to pain than in animals more sensitive to pain. In conclusion, the present study demonstrates unique data showing association between anxiety and nociceptive sensitivity of prenatally MA-exposed rats that is induced by acute drug administration

OBJEKTIVNÍ MĚŘENÍ ÚNAVY FREKVENCÍ MRKÁNÍ

In the article, the new possibility of registration of fatigue is described. The optoelectronic apparatus records the eye-blink rate which serves as an objective indicator of person's fatigue, especially at night. The results show that frequency of eye-blink rate is faster in the night than in the day. Described method can be used in drivers, which will be informed by warning acoustic signal about the risk of falling asleep when the frequency of eye-blink will reach individually critical level