Regional concentrations of insulin in the rat brain

Recent evidence that insulin receptors are concentrated in the hypothalamus and olfactory bulb suggests that insulin may have an important regulatory function in these regions. This hypothesis would be supported by finding that insulin itself is concentrated in the hypothalamus and olfactory bulb. Therefore, we extracted the hypothalamus and olfactory bulb, as well as the amygdala, hippocampus, cerebral cortex, hindbrain, midbrain, and whole brains, of fasted male Wistar rats and measured immunoreactive insulin (IRI). Recovery of insulin added to extraction volumes of 500-1000 microliters was 90-100%, whereas recovery of insulin from tissue extracts was 63%. Mean IRI concentrations were relatively uniform throughout the brain (0.19 ng/g wet wt; uncorrected for recovery) and were significantly lower than plasma levels (1.03 ng/ml). Nevertheless, IRI concentrations were significantly higher in hypothalamus (0.39 +/- 0.02 ng/g; P less than 0.01) and olfactory bulb (0.37 +/- 0.02 ng/g; P less than 0.05) compared to those in other brain regions sampled.     

Development of an education integrated design framework for the physical space of nursing homes in relation to life expectancy of the older people

The purpose of this research is to find design variables effective on education integration with physical spaces of nursing homes in association with life expectancy of older people. Delphi technique was used to obtain the design variables by which the education integration with physical spaces of nursing homes can be achieved. Subsequently, in order to investigate the modifying effect of education integrated physical space on life expectancy of the elderly, questionnaires were sent to 50 local researchers and experts in the field of ageing. Results showed a significant and positive correlation between education integrated physical space and life expectancy indicators (p < .05). The results suggest that as per expert opinions, designing a physical space integrated with education could increase the life expectancy of older people.     

Localization of 125I-insulin binding sites in the rat hypothalamus by quantitative autoradiography

In vitro autoradiography and computer video densitometry were used to localize and quantify binding of 125I-insulin in the hypothalamus of the rat brain. Highest specific binding was found in the arcuate, dorsomedial, suprachiasmatic, paraventricular and periventricular regions. Significantly lower binding was present in the ventromedial nucleus and median eminence. The results are consistent with the hypothesis that insulin modulates the neural regulation of feeding by acting at sites in the hypothalamus.     

Immunoreactive-β-endorphin and LHRH levels in the brains of aged male rats with impaired sex behavior

—Levels of immunoreactive β-endorphin and luteinizing hormone releasing hormone (LHRH) were measured in brain tissue of aged male Long-Evans rats. The animals were tested for sex behavior twice in one week at bimonthly intervals between the 7th and 27th month of life and were sacrificed along with a group of young (5-month old) sexually active rats. Thirty-one of the 89 rats which began the study remained healthy and tumor-free. By month 27, 21 of these had completely ceased to mate and 10 continued to show adequate sexual behavior. Diminished levels of β-endorphin-like immunoreactivity were measured in the hypothalami and hindbrain of the old animals grouped together as compared to young animals and this reduction was shown to be significantly greater in hypothalamic tissue from the behaviorally inactive subgroup. Hypothalamic LHRH levels were not significantly altered by age in these animals. However, a marked reduction of LHRH content in the septal and midbrain regions of the aged-behaviorally inactive subgroup was evident when compared with the behaviorally active group. The data suggest that altered function of β-endorphin and LHRH neurons of the aged brain may be involved in the behavioral deterioration observed in aged animals.     

Effect of remote ischemic postconditioning in inflammatory changes of the lung parenchyma of rats submitted to ischemia and reperfusion

Objective

To assess the effects of postconditioning remote in ischemia-reperfusion injury in rat lungs.

Methods

Wistar rats (n=24) divided into 3 groups: GA (I/R) n=8, GB (R-Po) n=8, CG (control) n=8, underwent ischemia for 30 minutes artery occlusion abdominal aorta, followed by reperfusion for 60 minutes. Resected lungs and performed histological analysis and classification of morphological findings in accordance with the degree of tissue injury. Statistical analysis of the mean rating of the degree of tissue injury.

Results

GA (3.6), GB (1.3) and CG (1.0). (GA GB X P<0.05).

Conclusion

The remote postconditioning was able to minimize the inflammatory lesion of the lung parenchyma of rats undergoing ischemia and reperfusion process.