Electron microscopic study of the mandibular glands of Kalotermes flavicollis Fabr. (Isoptera; Calotermitidae)

Summary The mandibular glands of Kalotermes were examined in different castes. They showed sexual dimorphism in the soldiers and primary reproductives. Moreover, in female soldiers and queens, mandibular gland cells contained numerous crystalline structures of mitochondrial origin. The role of these glands (secretion of saliva or pheromone) is discussed.

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Résumé Les glandes mandibulaires de Calotermes sont étudiées dans les différentes castes. Elles présentent un dimorphisme sexuel chez les soldats et les sexués. Après la mue imaginale, les cellules glandulaires ont toujours une activité sécrétrice. De plus, chez les soldats femelles et les reines, elles contiennent de nombreuses formations cristallines d'origine mitochondriale. Le rôle de ces glandes (sécrétion de salive ou de phéromone) est discuté.

     

Ultrastructure of the basiepithelial nerve plexus of the sea urchin,Centrostephanus longispinus

Summary In submandibular glands of rabbits both adrenergic and cholinergic axons are intimately associated with parenchymal cells of the intercalary ducts and the granular tubules, lying beneath the basement membrane and often in the space between the parenchymal cell and an associated myoepithelial cell. The submandibular acini receive a less intimate and less plentiful innervation by adrenergic and cholinergic axons which remain outside the basement membrane and are still associated with Schwann cells. Occasional axons of both adrenergic and cholinergic type occur beneath the basement membrane of submandibular striated ducts in intimate association with basal parts of the cells.In the parotid glands numerous adrenergic and cholinergic axons are found beneath the basement membrane of acini and intercalary ducts in intimate association with the cells.This work has been helped by the technical assistance of Mr. P.S.A. Rowley     

Opsonizing effect of serum and albumin gland extracts on the elimination of human erythrocytes from the circulation of Helix pomatia

The removal of human erythrocytes of the A₁ and B types from the circulation of the gastropod Helix pomatia follows an exponential curve. The elimination of the nonself particles is apparently dependent on serum opsonins as preincubation of A₁ and B erythrocytes in Helix serum increases the rate of their clearance. This conclusion is supported by our finding that secondary doses of nonsensitized A₁ erythrocytes injected 12–19 hr after a similar primary dose are cleared very slowly; however, the clearance rate returns to normal if erythrocytes comprising the second dose are preincubated with Helix serum. Furthermore, the elimination of second-dose A₁ erythrocytes is strongly enhanced after their pretreatment with agglutinating extracts of the albumin glands from H. pomatia and Cepaea (Helix) nemoralis. On the other hand, no opsonizing effect was obtained by pre-incubating A₁ erythrocytes in the agglutinating extract of the sponge Aaptos papillata.     

Gynandromorphs of the pycnogonid Anoplodactylus portus

A large sample of the pycriogonid Anoplodactylus portus , collected from the Pacific side of the Panama Canal Zone, contains a high percentage of gynandromorphs. The literature on aquatic arthropod gynandromorphs is outlined. The nature and variations of the sexual mosaic population are described and discussed. The several morphological differences between normal and mosaic members of the population are illustrated, and the possible origin of these gynandromorphs is discussed.     

K-induced alkalinization in all cell types of rabbit gastric glands: A novel K/H exchange mechanism

Digital image processing of the pH-sensitive dye BCECF was used to examine the effects of high [K] media on cytoplasmic pH (pHi) of individual cells within isolated rabbit gastric glands. When cells were acidified to pHi 6.5 from the resting pHi of 7.2-7.3 and then exposed to solution containing 77 mM K plus amiloride (to block Na/H exchange), recovery to pHi 7.0 was observed. This K-induced alkalinization occurred in all cell types of the gland, including cells within antral glands that were devoid of parietal cells (PC). This process was independent of extracellular Na and Cl and was unaffected by: 5 mM Ba or 200 microM bumetanide, or acute treatment with either 500 microM ouabain or 100 microM cimetidine, histamine or carbachol. SCH28080, which inhibits the PC H/K-ATPase when used in the low microM range of concentrations, blocked the K effect on pHi at 100 microM but was ineffective at 1 microM. A similar pHi recovery was also stimulated by Li, Cs (both 72 mM), and Tl (10 mM), in the order Li greater than K greater than Cs greater than Tl (all in the presence of amiloride), and these alkalinizations were also blocked by 100 microM SCH28080. Parallel experiments were performed to test the effect of these ions on 14[C]-aminopyrine accumulation, an index of acid secretion by the H/K-ATPase at the lumenal membrane of the PC. There was no correlation between the rates of cation-induced pHi recovery from an acid load and H secretion as measured by the accumulation of aminopyrine. We conclude that the K- (and Cs- and Li-) dependent pHi recovery is mediated by a novel cation/H exchange mechanism that is distinct from the PC H/K-ATPase.     

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.