Comparative study on cerebrovascular injuries by three chlorophenoxyacetic acids (2,4-D, 2,4,5-T and MCPA)

At toxic doses in rats, 2,4-dichlorophenoxyacetic acid (2,4-D) and 2-methyl-4-chlorophenoxyacetic acid (MCPA) caused injuries in blood vessels in the brain. 2. 2,4-D caused extravasations of the circulating Evans blue-albumin complex also in the spinal cord. 3. By contrast, potency in damaging cerebral vessels was almost non-existent with 2,4,5-trichlorophenoxyacetic acid (2,4,5-T). 4. None of the three chlorophenoxyacetic acids caused such cerebrovascular injuries in mice, guinea pigs, Syrian hamsters, rabbits and chickens.     

The first report on genetic variability and population structure in jackals from Bosnia and Herzegovina

Mammal Research - In recent years, the golden jackal (Canis aureus) has rapidly expanded its distribution throughout Europe. In Bosnia and Herzegovina, the jackal has also been found to have...     

新疆天山毛蠓属二新种：双翅目：蠓科

本文报道采自新疆天山的毛蠓属Ｄａｓｙｈｅｌｅａ２新种,分别为天山毛蠓Ｄ．ｔｉａｎｓｈａｎａｓｐ．ｎｏｖ．和高山毛蠓Ｄ．ｍｏｎｔａｎｓｐ．ｎｏｖ。模式标本保存在北京医学昆虫标本馆。     

云南省棘蝇属一新种：（双翅目：蝇科）

本文记述采自中国云南省的蝇科棘蝇属ＰｈａｏｎｉａＲ．－Ｄ．,１８３０１新种：小鸦棘蝇Ｐｈａｏｎｉａ ｌｅｐｔｏｃｏｒａｘ,ｓｐ．ｎｏｖ．。模式标本保存于沈阳师范学院生物系。     

Microfluorimetric quantification of catecholamine fluorescence in rat sympathetic ganglia

Summary The formaldehyde-induced fluorescence (FIF) technique was used to generate catecholamine fluorphores in the perikarya of the sympathetic neurons in the superior cervical ganglion of adult rats. During microfluorimetric quantification, the photodecomposition was eliminated by a rapid measuring procedure with a small excitation field and by using only visible light between the measurements.The catecholamine fluorescence, induced in protein microdroplets with increasing noradrenaline concentrations, was linear up to 2×10^–2 M which exceeds the noradrenaline content of even the most intensively fluorescent neurons. Thus, the differences in fluorescence intensities directly reflect the physiological state of each neuron with respect to their catecholamine content. The mean histograms reveal the changes which can only occur in certain neurons, and which can disappear if the mean only is assessed. The microfluorimetric method was sensitive enough to detect even minute changes induced by reserpine treatment in the catecholamine content of the sympathetic ganglion cells.     

Permanganate fixation demonstrates the monoamine-containing granular vesicles in the SIF cells but not in the adrenal medulla or mast cells

Summary Three types of monoamine-storing cells were fixed with permanganates and analyzed ultrastructurally. The SIF cells contained the typical granulated vesicles characteristic of monoamines. On the other hand, both the catecholamine-storing cells in the adrenal medulla and the mast cells were devoid of a dense core in their monoamine vesicles. This is surprising, since permanganate is considered a reliable means of demonstrating monoamines at the fine structural level. The significance of this finding is discussed against the close relationship between SIF cells and cells of the adrenal medulla. Because permanganate as a fixative is widely used in monoamine fine structural cytochemistry, the present findings undoubtedly need further clarification.     

Ultrastructural demonstration of amine granules in the adrenal medullary cells of the rat using acid permanganate fixation

Summary Potassium permanganate fixative is usually employed at pH 7.0. At this pH the amines in the granules of the adrenal medullary cells do not react with permanganate. When the pH was adjusted to 5.0, electron dense precipitates were seen in the amine granules of part of the medullary cells, probably noradrenalin containing cells.Supported by the grant from the Finnish Cultural Foundation     

Ultrastructural identification of monoaminergic synaptosomes from one day old rat brain

Summary Synaptosomes from one day old and adult rat brain were studied. Specific cytochemical methods for demonstrating monoaminergic (MA) nerve endings were used. Permanganate fixation after preincubation with 5-OHDA or -methyl-NA demonstrated MA synaptosomes. Their number was small in the adult (less than 1%) and still smaller in the one day old rat brain. The MA synaptosomes from developing rats were different from the adult ones. The large amount of endoplasmic reticulum in developing synaptosomes suggests that granular vesicles are formed from endoplasmic reticulum in nerve endings.     

Electron microscopic localization of adenylate cyclase activity of white and brown adipose tissue of the rat and chicken

Summary Brown adipose tissue of newborn rats and chicken embryos and white adipose tissue of adult rats were studied. Adenylate cyclase (EC 4.6.1.1.) activity stimulated by 0.1 mmol/l noradrenaline was demonstrated using an electron microscopic histochemical method.The reaction product was visualized as a cobalt salt in the plasmalemma of the adipocytes. The adipocytes of the brown adipose tissue of the newborn rats showed most intense reaction in the outer surfaces of their plasmalemma. Alloxan totally inhibited the enzymatic reaction.The histochemical reaction used in the present study probably demonstrated the hormonal receptor sites in the plasmalemmas of the adipocytes which are stimulated by noradrenaline.     

Catecholamine-synthesizing enzymes in paraganglia of aged Fischer-344 rats

Summary The catecholamine-synthesizing enzymes, tyrosine hydroxylase, dopamine--hydroxylase and phenylethanolamine-N-methyltransferase were examined by immunohistochemistry in hypertrophied paraganglia of aged male Fischer-344 rats. All paraganglionic cells reacted with antibodies against tyrosine hydroxylase. Dopamine -hydroxylase was identified in most paraganglionic cells, indicating that they synthesized norepinephrine. A variable number of paraganglia were positive for phenylethanolamine-N-methyltransferase, which suggested that they synthesized epinephrine. The formaldehyde-induced fluorescence method demonstrated greenish-yellow fluorescence or yellowish-brown fluorescence. The intensity of the fluorescence was in the same range as in adrenal medullary cells. The observations indicate that paraganglia are capable of synthesizing epinephrine.Dr. J.M. Stolk is the recipient of RSDA K2-00018 from the National Institute of Health.