Effects of epinephrine on thermoregulatory behavior in lean and obese Zucker rats in the cold

Relationship between Postoperative Complications and Ratio of Amount of Wetting Solution to Ideal Body Weight in Liposuction Procedures

BACKGROUND

The use of wetting solutions (WSs) during high-volume liposuction is standard; however, the optimal amount of WS and its components and their effect on postoperative complications are unclear. We evaluated the effect of a WS and its components, calculated according to ideal body weight (IBW), on postoperative complications.

METHODS

High-volume liposuction with a WS containing 0.5 g of lidocaine and 0.5 mg of epinephrine in each liter was performed in 192 patients. Patients who received ≤90 mL/kg of WS were designated as group I and those who received >90 mL/kg of WS as group II. Postoperative complications and adverse events that occurred until discharge were recorded.

RESULTS

The mean total amount of epinephrine in the WS was significantly higher for group II (3.5 mg; range, 3.0-4.0 mg) than for group I (2.0 mg; range, 1.8-2.5 mg; p < 0.001), as was the mean total amount of lidocaine (3.5 g [range, 3.5-4.3 g] vs. 2.0 g [range, 1.8-2.5 g], respectively; p < 0.001). No major cardiac or pulmonary complications occurred in either group. Administration of >90 mL/kg of WS increased the median risk of postoperative nausea 5.3-fold (range, 1.8- to 15.6-fold), that of hypertension 4.9-fold (range, 1.1- to 17.7-fold), and that of hypothermia 4.2-fold (range, 1.1- to 18.5-fold). The two groups had similar postoperative pain scores and blood transfusion rates.

CONCLUSIONS

The risks of postoperative nausea, vomiting, hypothermia, and hypertension may increase in patients who receive >90 mL/kg of WS calculated according to IBW during high-volume liposuction.

Biothermodynamic Assay of Coptis-Evodia Herb Couples

Objective. To illustrate the difference in cold/hot natural properties and therapeutic effect of coptis-evodia herb couples by using cold/hot plate differentiating technology and microcalorimetry combined with material basis analysis in vivo and in vitro. It showed that animal retention ratio in hot pad significantly decreased along with the decrease in coptis proportion in coptis-evodia herb couples. In addition, Zuojin wan markedly reduced the retention ratio of gastritis mice in the hot pad, while Fanzuojin wan displayed an opposite result. Further, Mg²⁺-ATPase, Ca²⁺-ATPase, and T-AOC activity significantly weakened in coptis-treated group in the livers of the mice. In the gastric cells from the gastritis mice, Fanzuojin wan remarkably increased calorific value for growth and metabolism, while Zuojin wan significantly reduced the calorigenic effect. It suggested that the changes in the major chemical compositions (especially alkaloids) were the material base-induced transformation between “cold” and “hot” syndromes. The material basis which affected the transformation between “cold” and “hot” syndromes might be X₂, X₃, X₄, X₈, epiberberine hydrochloride, jatrorrhizine hydrochloride, coptisine sulphate, palmatine hydrochloride, and berberine hydrochloride. The CHPD combined with microcalorimetry technology is a good method to determine the differences in the “cold” and “hot” natural properties of coptis-evodia herb couples.

Study on the cold and hot properties of medicinal herbs by thermotropism in mice behavior

It is a common sense that chewing a mint leaf causes a cold feeling, while masticating a piece of ginger root is associated with a hot sensation. The Traditional Chinese Medicine has termed this phenomenon as cold and hot properties of herbs and applied them in treating certain human diseases successfully for thousands of years. Here, we have developed an Animal Thermotropism Behavior Surveillance System, and by using this device and other approaches, we not only verified the existence of, but also characterized and quantitated the cold and hot properties of medicinal herbs in animal behavioral experiments. The results suggested that the hot and cold properties of herbal drugs indeed correlated with the alteration of animal behavior in search for residence temperature.

Thermal preference behavior following clonidine, norepinephrine, isoproterenol, and ephedrine

A thermal gradient (temperature range 7-45 degrees C) was used to assess ambient temperature (Ta) preferences of rats following treatment with clonidine (25 microg/kg), norepinephrine (NE, 250 microg/kg), isoproterenol (ISO, 50 microg/kg), and ephedrine (EPH, 10 mg/kg). Clonidine produced a preference for a temperature (31.5 degrees C) slightly warmer than that preferred after saline (28.3 degrees C), but this resulted in no significant change in posttest colonic temperature (Tc). NE, ISO and EPH produced a preference for a colder region of the gradient (20-22 degrees C) compared to saline (24.5-28.9 degrees C). Posttest Tc was reduced significantly from 37.7-37.9 degrees C after saline to 37.2 degrees C (NE), 37.3 degrees C (ISO), and 36.8 degrees C (EPH). Thus, given the opportunity to select an environmental temperature, the animals selected a Ta that resulted in significantly lower body temperatures after NE, ISO, and EPH. This suggests that paradoxical thermoregulatory effects of these thermogenic adrenergic agonists are due, at least in part, to a preference for a lower body temperature.

Effects of alpha 1-adrenoceptor and Ca2+ channel inhibition on norepinephrine-induced thermoregulatory behavior in the cold

This experiment examined whether paradoxical temperature-dependent effects of norepinephrine (NE) can be blocked by the alpha 1-adrenoceptor antagonist WB 4101 (WB) and the Ca(2+)-channel blocker nifedipine. An operant lever-pressing task was used to measure the demand for heat in a cold environment. As noted previously, NE alone (250 micrograms/kg) produced a substantial and significant increase in the demand for heat, and yet post-test colonic temperature (Tc) fell. When tested alone, WB and nifedipine also increased the demand for heat, but this was sufficient to maintain Tc. When combined with NE, WB and nifedipine reduced the demand for heat and the fall in Tc such that there were no differences between the effects of the blockers given alone or with NE. These results indicate that paradoxical thermoregulatory effects of NE in the cold can be antagonized effectively by either an alpha 1-adrenoceptor antagonist or a Ca(2+)-channel blocker.

Temperature-dependent effects of ephedrine in the cold

This experiment examined the effects of intraperitoneal ephedrine (5-25 mg/kg) on operant thermoregulatory behavior of rats in the cold (-8 degrees C), and of 10 mg/kg on metabolic rate at a thermoneutral (22 degrees C) ambient temperature (Ta) and in the cold (5 degrees C). Posttest colonic temperature (Tc) decreased dose-dependently in the behavioral tests, yet the demand for heat varied little with respect to saline except for a significant reduction at the lowest dose tested (i.e., there was no compensation for the reduced Tc induced by ephedrine). Ephedrine had a potent thermogenic effect at a Ta of 22 degrees C, increasing both metabolic rate and Tc. In the cold, ephedrine reduced Tc, but this effect could not be accounted for by a reduction in metabolism, which was not significantly different from saline.

Temperature-dependent effects of alpha-adrenergic agonists and antagonists in the cold

This series of experiments examined whether temperature-dependent effects of the alpha-antagonists prazosin and yohimbine compromised their use as blockers of alpha-adrenergic agonist responses in cold-exposed rats. An operant leverpressing task was used to measure the demand for heat in a cold environment. The alpha 1-antagonist prazosin had modest effects, but the alpha 2-antagonist yohimbine was thermolytic in that it dose dependently increased operant responding but decreased posttest colonic temperature (Tc). These potent effects of the alpha 2-antagonist led to tests of the alpha 2-agonist clonidine. Clonidine increased operant responding for heat to an extraordinary degree, resulting in significant increases in posttest Tc. However, clonidine was found to be a hypothermic agent when tested in rats at 5 degrees C but denied the opportunity to increase body temperature by operant lever pressing, suggesting a central effect on the control of thermal balance. Measurement of changes in metabolic rate at 5 and 23 degrees C showed that yohimbine increased metabolism at 23 degrees C but decreased it in the cold. Prazosin had little effect on metabolism or Tc at either temperature. Prazosin inhibited the decrease in Tc induced by norepinephrine (NE), but had little effect on the lever-pressing response. Yohimbine had no significant antagonistic effect on NE-induced changes in lever-pressing behavior or posttest Tc, but neither did the thermolytic effects of yohimbine exacerbate those of NE. These results show that alpha-antagonist interactions with agonists can be complicated by temperature-dependent effects of each.