Background： Olfactory disorder is an early manifestation of Parkinson＆#39;s disease （PD）, likely to be associated with abnormalities of the dopaminergic neurons in the olfactory bulb （OB）; however, the causes of...Background： Olfactory disorder is an early manifestation of Parkinson＆#39;s disease （PD）, likely to be associated with abnormalities of the dopaminergic neurons in the olfactory bulb （OB）; however, the causes of olfactory disorder in PD are not entirely clear. Some studies showed that melatonin （MT） and androgens （mainly testosterone, T） might participate in the pathogenesis of PD. The research aimed to investigate effects of MT or T deficiency on OB dopaminergic neurons in rats. Methods： One hundred and twenty normal male Wistar rats were randomly divided into the control, sham operation pinealectomy （PX）, sham operation gonadectomy （GDX）, PX, GDX, and PX ＋ GDX groups. After 60 days, glial cell hyperplasia and neuronal apoptosis were examined with hematoxylin and eosin and the TUNEL method; the expression levels of tyrosine hydroxylase （TH）, Bax, and Bcl-2 were measured using immunohistochemistry （IH） by the streptavidin peroxidase conjugated method. Comparison among multiple sets used analysis of variance and LSD method or Kruskal-Wallis test and Nemenyi method. Results： There were no significant differences between the sham operation groups and the control group; thus, they were merged into Group A. There was no significant glial cell hyperplasia （P 〉 0.05） or change in shape in any of the groups after PX or GDX. The number of apoptotic cells in Groups A （1.41 ± 0.56）, PX （12.31 ± 4.68）, GDX （20.52 ± 5.13）, and PX ＋ GDX （30.23 ± 5.25） successively significantly increased （P 〈 0.05）. The number of TH （＋） cells in Groups A （42.62 ± 5.63）, PX （37.31 ± 4.32）, GDX （31.07 ± 4.21）, and PX ＋ GDX （25.22 ± 3.66） was successively significantly decreased （P 〈 0.05）. The gray value of TH （＋） cells and fibers in Groups A （98.51 ± 10.36）, PX （108.96 ± 13.01）, GDX （119.02 ± 12.98）, and PX ＋ GDX （128.99 ± 13.39） was successively significantly increased （P 〈 0.05）. The results of Bax staining were as follows： Group A＋, Group PX＋＋, Group GDX＋＋, and Group PX＋ GDX＋＋＋, the results of Bcl-2 in all groups were ＋. Conclusions： PX or GDX could lead to OB neurotoxicity in the following groups of rats in the following order： PX 〈 GDX 〈 PX ＋ GDX. PX or GDX increased the ratio of Bax/Bcl-2. The effect of PX and GDX was equal, but both were less than that of PX ＋ GDX. Neurotoxicity as a result of PX or GDX was not related to inflammation.展开更多
Behavioral studies have shown that flank glands are involved in chemical communication in golden hamsters Mesocricetus auratus but little chemical analysis has been conducted on volatiles arising from these glands. Us...Behavioral studies have shown that flank glands are involved in chemical communication in golden hamsters Mesocricetus auratus but little chemical analysis has been conducted on volatiles arising from these glands. Using gas chromatography-mass spectrometry, we detected compounds from the flank glands of males, only eight of which were also produced in females. Based on these chemical data we performed a number of further experiments. By manipulating light we found that males exposed to short-photoperiods developed smaller flank glands than those exposed to long-photoperiods. Six flank gland volatiles reduced in relative abundance, which possibly coded for reproductive status of males of this seasonally breeding hamster species. Through dyadic encounters, we were able to induce the formation of dominant-subordinate relationships and show that two glandular compounds became high in relative abundance and may function as dominance pheromones. Castration eliminated all male-specific compounds resulting from flank glands, but bilateral ovariectomies only affected one compound in females. Once these ovariectomized females were treated with testosterone, their glandular compounds resembled those of males, suggesting these compounds are under the main control of androgen. Two female putative pheromones, tetradeeanoic acid and hexadecanoic acid, were used in binary choice tests and were both found to attract males over females. Applying a solution of these pheromone compounds to adult males also suppressed their agonistic behavior [Current Zoology 56 （6）： 800-812, 2010].展开更多
文摘Background： Olfactory disorder is an early manifestation of Parkinson＆#39;s disease （PD）, likely to be associated with abnormalities of the dopaminergic neurons in the olfactory bulb （OB）; however, the causes of olfactory disorder in PD are not entirely clear. Some studies showed that melatonin （MT） and androgens （mainly testosterone, T） might participate in the pathogenesis of PD. The research aimed to investigate effects of MT or T deficiency on OB dopaminergic neurons in rats. Methods： One hundred and twenty normal male Wistar rats were randomly divided into the control, sham operation pinealectomy （PX）, sham operation gonadectomy （GDX）, PX, GDX, and PX ＋ GDX groups. After 60 days, glial cell hyperplasia and neuronal apoptosis were examined with hematoxylin and eosin and the TUNEL method; the expression levels of tyrosine hydroxylase （TH）, Bax, and Bcl-2 were measured using immunohistochemistry （IH） by the streptavidin peroxidase conjugated method. Comparison among multiple sets used analysis of variance and LSD method or Kruskal-Wallis test and Nemenyi method. Results： There were no significant differences between the sham operation groups and the control group; thus, they were merged into Group A. There was no significant glial cell hyperplasia （P 〉 0.05） or change in shape in any of the groups after PX or GDX. The number of apoptotic cells in Groups A （1.41 ± 0.56）, PX （12.31 ± 4.68）, GDX （20.52 ± 5.13）, and PX ＋ GDX （30.23 ± 5.25） successively significantly increased （P 〈 0.05）. The number of TH （＋） cells in Groups A （42.62 ± 5.63）, PX （37.31 ± 4.32）, GDX （31.07 ± 4.21）, and PX ＋ GDX （25.22 ± 3.66） was successively significantly decreased （P 〈 0.05）. The gray value of TH （＋） cells and fibers in Groups A （98.51 ± 10.36）, PX （108.96 ± 13.01）, GDX （119.02 ± 12.98）, and PX ＋ GDX （128.99 ± 13.39） was successively significantly increased （P 〈 0.05）. The results of Bax staining were as follows： Group A＋, Group PX＋＋, Group GDX＋＋, and Group PX＋ GDX＋＋＋, the results of Bcl-2 in all groups were ＋. Conclusions： PX or GDX could lead to OB neurotoxicity in the following groups of rats in the following order： PX 〈 GDX 〈 PX ＋ GDX. PX or GDX increased the ratio of Bax/Bcl-2. The effect of PX and GDX was equal, but both were less than that of PX ＋ GDX. Neurotoxicity as a result of PX or GDX was not related to inflammation.
基金supported by grants from the National Basic Research Program of China (973 Program,no.2010CB833900-2)the Chinese NSF (no.30870297)
文摘Behavioral studies have shown that flank glands are involved in chemical communication in golden hamsters Mesocricetus auratus but little chemical analysis has been conducted on volatiles arising from these glands. Using gas chromatography-mass spectrometry, we detected compounds from the flank glands of males, only eight of which were also produced in females. Based on these chemical data we performed a number of further experiments. By manipulating light we found that males exposed to short-photoperiods developed smaller flank glands than those exposed to long-photoperiods. Six flank gland volatiles reduced in relative abundance, which possibly coded for reproductive status of males of this seasonally breeding hamster species. Through dyadic encounters, we were able to induce the formation of dominant-subordinate relationships and show that two glandular compounds became high in relative abundance and may function as dominance pheromones. Castration eliminated all male-specific compounds resulting from flank glands, but bilateral ovariectomies only affected one compound in females. Once these ovariectomized females were treated with testosterone, their glandular compounds resembled those of males, suggesting these compounds are under the main control of androgen. Two female putative pheromones, tetradeeanoic acid and hexadecanoic acid, were used in binary choice tests and were both found to attract males over females. Applying a solution of these pheromone compounds to adult males also suppressed their agonistic behavior [Current Zoology 56 （6）： 800-812, 2010].
