摘要:

AbstractRadioautography demonstrates that the injection of3H‐cholesterol into larval and adult sea lamprey,Petromyzon marinusL., results in labelling of their presumptive interrenal cells. This localization of cholesterol and/or its metabolites is: (1) further evidence for the homology of these cells with adrenocortical cells of higher vertebrates and (2) a suggestion of the possibility that these cells in lampreys are able to absorb cholesterol for utilization in corticosteroid synthesi

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1975.tb00099.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

AbstractNumerous fluorescent varicosities surround most of the caudal neurosecretory neurons and also regularly occur among pars intermedia cells of the adenohypophysis in the teleost,Gillichthys mirabilis.The color of the varicosities, as well as their responses to pharmacological treatments, is diagnostic of catecholaminergic neurons and processes. No fluorescence characteristic of monamines is found in the rostral pars distalis, in the proximal pars distalis or in the cells of the nucleus lateralis tuberis (NLT), although fluorescent varicosities are found within the ventral hypothalamus in the vicinity of the NLT. Bilateral clusters of fluorescent cell bodies are located in the ventral hypothalamus (posterior to the NLT); some of these cells border the neurohypophysis. Fluorescent tracts from these cell clusters extend to a pair of elongate nuclei of nonfluorescent neurons which are surrounded by fluorescent varicosities. Alteration of osmotic conditions did not effect the fluorescence, except for the caudal neurosecretory cells of fish exposed to fresh water for long periods. Adrenergic nervous input thus seems to be an important component of both the cranial and caudal neurosecretory systems.

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1975.tb00100.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

AbstractInvestigations on the circadian cycle of secretion in the neurosecretory nuclei of mouse.The circadian cycle of secretion of both hypothalamic neurosecretory nuclei N. supraopticus and N. paraventricularis in mice was studied by histological, histochemical, biochemical and electron‐microscopical methods. Both areas undergo a circadian secretion cycle (24 h‐rhytm).The activity of metabolism increases at the beginning of night, whereas by day the cells are considered to be in a phase of restitution and transportation of the secretion. Especially increases the volume of the cell nuclei (synthesis of RNA and proteins) and the activity of the extralysosomal unspecific esterase rises to maximal values.From midnight till the beginning of the light‐phase the cells show a maximal volume of the nuclei and an increased secretion as well as higher activity of acid phosphatase and lactate dehydrogenase. Unspecific esterase activity, on the other hand, diminished. There was a noticable increase in the quantity of neurosecretion in both areas, it reached a maximum at the beginning of the light‐phase, whereas the volume of the nuclei and the activity of acid phosphatase and thiamine pyrophosphatase diminished. The neurosecretion is more and more transported to the hypophysis. The cells restitute during the light‐phase and reach their start

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1975.tb00101.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

AbstractThe ependymal cells of both dorsal and ventral walls lining the lumen of the neurohypophysis of the hagfish,Eptatretus burgeri, absorb peroxidase injected into the third ventricle. Peroxidase diffuses rapidly into the connective tissue separating the neurohypophysis from the adenohypophysis, and also into the connective tissue located between the cell nests of the adenohypophysis.

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1975.tb00102.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

AbstractUltrastructural investigation of the caudal muscle cells in the tadpole larva of the ascidianDendrodoa grossulariahas shown that in this species, a transverse tubular system is present; diad and triad couplings are formed with the sarcoplasmic reticulum. Peripheral couplings of the sarcoplasmic reticulum are infrequent and have only been observed at the longitudinally apposed faces of the caudal muscle cells.

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1975.tb00103.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

AbstractA gizzard is recorded for the first time in a bryozoan,Hippothoa divaricatavar.conferta, of the order Cheilostomata.

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1975.tb00104.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

AbstractThe gizzard teeth of a bryozoan(Bowerbankia imbricata) are found to be the structural homologues of certain epidermal derivatives, popularly known as “annelid‐like”

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1975.tb00105.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY