Ultrastructure and nature of secretory proteins in the male accessory gland of Drosophila funebris

The ultrastructural differentiation of the secretory cells and the nature of secretory proteins in the male accessory gland of Drosophila funebris have been studied by electron-microscopic and immunological methods. (1) In the pupae at $\text{1}\text{1}\text{2}$ days before eclosion, secretory products can be detected in the lumen, even though most glandular cells are at the initial phase of differentiation. At the time of eclosion both main and secondary cells are fully differentiated, but the whole set of five immunologically active proteins are detectable only on the second to third day of adult life. (2) The secondary cells contain giant protein granules, the so-called filamentous bodies, which become partially fused and the filaments assume a twisted form. Randomly dispersed filaments and closely packed filament bundles are also visible in the gland lumen. Antigenic labelling of ultrathin sections and immunoreplica electrophoresis yielded no evidence for the microtubular nature of these filaments. The secretion stored in the lumen contains in addition a large quantity of flocculent proteins which have their origin in the main cells. (3) During the period of high secretory activity in the 7-day-old male flies no vacuolization and disintegration of either the main or secondary cells have been observed. We conclude that both types of cells have the merocrine secretory mechanism. (4) Ultrastructural alterations in the glandular cells confirmed our previous observation that copulation stimulates RNA and protein synthesis.     

The hormonal control of accessory reproductive gland development in female Schistocerca gregaria

Allatectomy of adult female Schistocerca gregaria prevents the normal development of the accessory reproductive glands and no secretion is produced. Development of the glands can be restored by the administration of synthetic juvenile hormone and the response is dose-dependent. A continuous supply of hormone is required for maintenance of secretory activity. In the normal developmental sequence the total protein content of the glands remains constant until the time at which vitellogenesis occurs in the terminal oöcytes. As maturation proceeds there is a linear increase in protein content of the glands. The initial increase occurs as a result of cellular changes in the glands and is then followed by an increase due to an accumulation of secretion in the lumina.     

Characteristics of development and variations in ecdysteroid levels in Clitumnus embryos deprived of their cephalic endocrine glands

Microsurgical suppression of presumptive endocrine areas in very young embryos of Clitumnus resulted in an arrest in development, which occurred at different stages according to the operation. In most cases however. the duration of embryonic life was not reduced significanly. The repercussions of each operation type on the ecdysteroid content of the embryos were determined using a radioimmunoassay technique.Consideration of the experimental results provides some indication on the part played by each endocrine formation during the last part of embryonic development that is between dorsal closure and hatching time. Our experiments offer original evidence that the corpora allata of the embyro are of utmost importance at the stage VII_3t, in initiating the normal expression of larval characteristics.     

Social status, activity and preputial glands of wild and domestic house mice

Scent marking by deposition of urine, and the preputial glands, of adult, male, wild house mice, Mus mmmlus L., were studied and compared with those of an outbred domestic strain. The preputial glands of dominant wild mice were always heavier than those of subordinates. No dominance relationships could be established among the domestic mice. For study of scent marking each mouse was observed singly in a residential maze. Dominant wild mice marked more than the subordinates. The domestic mice scent-marked much less even than the subordinate wild mice. Subordinate wild mice spent less time than the dominant wild mice outside the nest; but the number of excursions outside the nest made by the subordinates resembled that of the dominants. Hence social status influenced the pattern of movements in a structured environment.     

Effects of host endocrine gland removal on the permissive status of laboratory rodents to infection by Schistosoma mansoni

Knopf P. M. and Soliman M. 1980. Effects of host endocrine gland removal on the permissive status of laboratory rodents to infection by Schistosoma mansoni. International Journal for Parasitology, 10: 197–204. The capacity of Schistosoma mansoni to complete its life cycle was compared in CD-1 mice (permissive hosts) and Sprague-Dawley rats (nonpermissive hosts) from which the pituitary gland had been removed prior to infection with cercariae. Except for a modest decrease in egg burden, none of the parameters of worm life cycle assessed were affected in hypophysectomized mice. In contrast, all these parameters were affected in hypophysectomized rats, e.g. onset of adult worm elimination was delayed, worm development improved, oviposition increased and miracidia developed. Effects of removal from rats of the thyroid/parathyroid glands on the parasite life cycle were similar to hypophysectomy; adrenalectomy or gonadectomy were without affect. Differences between thyroidectomized and thymectomized rats are discussed. It is concluded that host hormones contribute to the nonpermissive status of rats to Schistosoma mansoni infections.     

Ecdysterone antagonism,mimicry, and synergism of juvenile hormone action on the Monarch butterfly reproductive tract

Previous research on Monarch butterflies has shown that juvenile hormone (JH) stimulates the development of the ovary and certain reproductive glands of both sexes. Ecdysterone injections into intact Monarchs demonstrate that low doses of this hormone inhibit ovarian development, and higher doses stimulate the male and female reproductive glands. In addition, experiments using neckligatured adults show that ecdysterone stimulates the reproductive glands of both sexes, in the apparent absence of JH, with the most pronounced effect being observed on the female colleterial gland. Other studies with neck-ligatured animals demonstrate that ecdysterone also synergizes with JH on the female gland and all three male glands. The feasibility of using Monarch reproductive glands for studies on the mode of action and interaction of JH and ecdysterone, and the possibility of a rôle of ecdysterone in the normal regulation of Monarch oögenesis, are discussed.     

Intestinal endocrine cells of chicks around the time of hatching

Summary The duodenum of 16-day Black Australorp chick embryos, and the duodenum, ileum, large intestine and caeca of 18-day embryos and of chicks within 30 h of hatching, have been studied by electron microscopy. Cells were found with secretory granules resembling those in mammalian EC, S, A-like, EG and D cells (terminology of Solcia et al., 1973), and were on this basis tentatively identified accordingly. The distribution and frequency of the chick cells in different parts of the tract correspond well to the situation in mammals.Supported by grants from the Senate Research Committee of the University of the Witwatersrand, JohannesburgThe author gratefully acknowledges the help of Professors E. Solcia and N. Ferreira     

Etude ultrastructurale de l'innervation des glandes salivaires postérieures chez Octopus vulgaris

Résumé Le canal salivaire contient dans sa paroi deux types de nerfs, moteurs et sécréteurs. Le diamètre des fibres nerveuses est en moyenne plus faible dans les nerfs moteurs, où il diminue encore en direction des glandes, tandis qu'au contraire celui des fibres sécrétrices augmente, accentuant ainsi les différences morphologiques entre les deux ners. Ces différences de calibre entre les fibres sont en rapport avec le nombre plus ou moins élevé des neurites qu'elles comportent, et dont les mésaxones ont des formes variées. Les caractères cytologiques des cellules satellites et des axones des deux types de nerfs sont comparables. Les axones contiennent des vésicules de types morphologiques très divers dont la signification est discutée.

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Ultrastructural study of the innervation of the posterior salivary glands in Octopus vulgaris I. The nervous trunks of the salivary duct

Summary Two types of nerves, motor and secretory, are found in the wall of the salivary duct. The average diameter of the motor fibers is smaller and decreases still more towards the glands, while on the contrary it increases for the secretory fibers. The disparity of diameter between the two types of fibers is due to the different number of neurites they contain, embedded in satellite cells with mesaxons of various forms. Axons and satellite cells have similar cytological features in the two types of nerves. Vesicles of several morphological types occur in the axons; their significance is discussed.

     

黑缘烟蟋螽丝腺结构

【目的】蟋螽是直翅目中唯一具有吐丝筑巢行为的类群。本研究旨在探讨蟋螽丝腺的结构特点。【方法】应用解剖学观察、免疫荧光、苏木精-伊红染色、PAS苏木精染色、扫描电镜和透射电镜等方法从细胞水平对黑缘烟蟋螽Capnogryllacris nigromarginata丝腺的显微与超微结构进行了观察。【结果】黑缘烟蟋螽丝腺由导管和腺泡构成。腺泡由鞘细胞延伸形成的结缔组织鞘包围。腺泡的主体有4种细胞,分别为Ⅰ型分泌细胞、Ⅱ型分泌细胞、围细胞和腔细胞。Ⅰ型和Ⅱ型分泌细胞为大的腺细胞,形状不规则。分泌细胞细胞核很大,胞质内有大量的内质网和分泌颗粒。Ⅰ型分泌细胞靠近腺泡中心,PAS-苏木精染色表明Ⅰ型分泌细胞内含糖蛋白,Ⅱ型分泌细胞在腺泡外周,位于Ⅰ型分泌细胞与围细胞或结缔组织鞘之间。腔细胞分散在分泌细胞之间,包围形成胞外运输分泌物的通道。围细胞与鞘细胞接触,具有由细胞膜内陷形成的微绒毛腔,胞质内有大量的线粒体。围细胞微绒毛腔与腔细胞包围的细胞外运输通道相连,分泌细胞分泌的颗粒聚集在分泌细胞和胞外运输通道之间的连接处,并将分泌物排出至胞外运输通道。多个腺泡的胞外运输通道汇集到由单层细胞组成的丝腺导管。单层导管细胞靠近管腔外围具有规则排列的质膜内陷和大量伸长的线粒体;靠近管腔的一侧具连续的细胞膜突起,在导管壁的表皮下紧密排列。【结论】黑缘烟蟋螽丝腺分泌细胞分为Ⅰ型分泌细胞和Ⅱ型分泌细胞。分泌物质产生及分泌过程依次经过分泌细胞、腔细胞包围的胞外通道、分支导管、总导管和唾窦。其中在腺泡细胞之间,分泌物向外运输过程中,围细胞微绒毛腔的微丝束可能对分泌物的外排提供推动力。