摘要:

AbstractThe sperm cells ofNymphon leptochelesandN. rubrumare of the primitive type, which is a remarkable condition among arthropods. The motile sperm consist of a somewhat elongated head, a kind of midpiece and a long tail. An acrosome is absent. The nucleus is surrounded by longitudinally oriented microtubules running in furrows in the nuclear envelope. These microtubules are not interconnected by links or connected to the nuclear envelope; they persist in the mature sperm. No appreciable chromatin condensation takes place. The midpiece contains some unmodified mitochondria and a centriole. The tail is a simple, free flagellum. The results are in particular discussed in relation to other known microtubule‐nuclear envelope complexes in sperm cells. The sperm cells ofPycnogonum littoraleare, on the other hand, highly aberrant. They are unmotile, elongated cells containing a very high number (often more than 1000) of longitudinal microtubules arranged in complex patterns. Some folded membranes may represent the nuclear envelope. Other organelles are unidentificable or may be absen

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1974.tb00189.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

AbstractOn the basis of autoradiographical investigations with tritiated serotonin or N adrenaline and histochemical studies, it was possible to describe a mechanism of cell migration in which these biogenic amines play a role in the presence of acid mucopolysaccharides and collagen. They may also have a role by provoking the formation of necrotic areas in which the mucopolysaccharides appear.

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1974.tb00190.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

AbstractThe lithium ion has an inhibitive effect on cicatrisation and regeneration ofDugesia tigrinaandClava squamatawhile 5‐hydroxytryptophan and α‐methyl DOPA have a protective one. It seems that these substances as well as the biogenic amines 5‐hydroxytryptamine and N‐adrenaline play a role during the cell migrations which underly morph

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1974.tb00191.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

AbstractThe erythrocytes of larval and adultLampetra fluviatiliswere examined in suspensions of whole blood, solutions of various ionic strengths, scanning electron photomicrographs and air dried smears. Although a wide range of shapes were observed in hyper‐ and hypotonic solutions, the cells in whole blood and isotonic solutions were predominantly biconcave with an eccentric nucleus. The biconcave shape was also seen in scanning electron photomicrographs of erythrocytes fixed with glutaraldehyde in lamprey Ringer. The mean diameter of larval and adult cells in whole blood suspensions was 11.2 and 11.6 μm respectively. Although in air dried smears the areas of the larval and adult erythrocytes were virtually identical, the erythrocyte nuclear area was markedly higher in ammocoetes with only a small amount of overlap between the values obtained for the two stages in the life cyc

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1974.tb00192.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

AbstractThe distribution of biogenic amines in the young pluteus ofPsammechinus miliarisGmelin was examined by means of the histochemical fluorescence method of Falck and Hillarp.Two different systems where monoamines occur were detected. Catecholamines were mainly found in a presumably impulse propagating neuron‐like system, while 5‐HT (serotonin) was predominantly localized in the endoderm wall. The results are discussed in relation to the ontogeny and phylogeny of sea urch

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1974.tb00193.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

AbstractThree endocrine cell types were recognized in the proximal pars distalis (PPD) of the roach,Leuciscus rutilus, by electron microscopy. Two of these cell types are basophilic and assumed to be gonadotropic. The third cell type is acidophilic and its similarity to somatotropic (STH) cells is evident. Green fluorescent cells corresponding to cells with dense core vesicles of about 85 nm are scattered between the PPD and the proximal neurohypophysis (PNH). Their possible content of a catecholamine was demonstrated with microspectrofluorometric analyses.Four axon types with granules 65, 81, 110 and 137 nm in average diameter terminate at the basement membrane. Only fibers with granules of 81 nm enter the PPD to make synapses with the STH cells. Extensions of the basement membrane are continuous with the perivascular space and penetrate the endocrine tissue. It is postulated that axon terminals on the basement membrane are functionally equivalent to synaptic contacts on the endocrine cells.Axon type 4 has granules which in sizes correspond to those of cells in lateral and ventrolateral parts of thenucleus lateralis tuberis(NLT). A similar correlation is possible between axon type 3 and other cells in the NLT. This is in accordance with earlier conclusions of a regulation of the gonadotropic cells from the lateral (posterior) parts of the NLT.

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1974.tb00194.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

AbstractPituitaries removed fromTilapia mossambicaadapted either to sea water or fresh water were incubated for 3 or 6 hours in isosmotic or hyposmotic medium. Activation of prolactin cells from pituitaries incubated in hyposmotic medium was indicated by frequent exocytosis and by proliferation of cellular organelles. These pituitaries also showed a reduction in prolactin content and an increase in the amount of bioassayable prolactin in the medium. Incorporation of tritiated leucine into prolactin was least in prolactin cells from seawaterTilapiaincubated in isosmotic medium and greatest in those of freshwaterTilapiaincubated in hyposmotic medium. These observations indicate that inTilapia, both synthesis and secretion of prolactin may be stimulated directly by dilution of the medium bathing the pituitary. On the other hand, there were no ultrastructural changes in the presumptive growth hormone cells incubated for 3 or 6 hours in the hyposmotic medium. Hence, these cells do not appear to play a major osmoregulatory role.

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1974.tb00195.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

AbstractAn electron microscopical study was made on the Sertoli cell in testicular lobules carrying mature spermatozoa in the newt,Trituroides hongkongensis.The ultrastructural features suggested that the Sertoli cells in newt might be capable of performing three possible functions: one, as a support for spermatozoa; two, carrying out phagocytosis; and thirdly, facilitate the liberation of spermatozoa.

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1974.tb00196.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

摘要:

AbstractThe parasitic male deep‐sea angler‐fishEdriolychnus schmidtiRegan 1925, which was described by Regan and Trewavas 1932, was reinvestigated with respect to the endocrine organs. Although the original microscopical sections are not in a good condition, it could be concluded that those organs which are involved in regulation of various internal environmental factors, as well as those involved in adaption to external factors, appear poorly developed or reduced. Mechanisms regulating reproductive activities seem to be well developed; a pronounced tuberis region is seen in the otherwise reduced brain and the peculiar pituitary gland appears to contain secretory active ce

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1974.tb00197.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1974.tb00198.x

出版商:Blackwell Publishing Ltd    

年代:1974

数据来源: WILEY