The Neurosecretory System Is Hypertrophied in Senescence-Accelerated Mice

AbstractReduction of elastin in the skin causes various skin diseases as well as wrinkles and sagging with aging. Sialidase is a hydrolase that cleaves a sialic acid residue from sialoglycoconjugate. Cleavage of sialic acid from microfibrils by the sialidase isozyme Neu1 facilitates elastic fiber assembly. In the present study, we showed that a lower layer of the dermis and muscle showed relatively intense sialidase activity. The sialidase activity in the skin decreased with aging. Choline and geranate (CAGE), one of the ionic liquids, can deliver the sialidase subcutaneously while maintaining the enzymatic activity. The elastin level in the dermis was increased by applying sialidase from Arthrobacter ureafaciens (AUSA) with CAGE on the skin for 5 days in rats and senescence-accelerated mice prone 1 and 8. Sialidase activity in the dermis was considered to be mainly due to Neu2 based on the expression level of sialidase isozyme mRNA. Transdermal administration of Neu2 with CAGE also increased the level of elastin in the dermis. Therefore, not only Neu1 but also Neu2 would be involved in elastic fiber assembly. Transdermal administration of sialidase is expected to be useful for improvement of wrinkles and skin disorders due to the loss of elastic fibers.

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Activation of the peptidergic neurosecretory system in Diphyllobothrium dendriticum (Cestoda: Pseudophyllidea)

Parasitology ◽

10.1017/s0031182000085243 ◽

1981 ◽

Vol 83 (2) ◽

pp. 243-247 ◽

Cited By ~ 24

Author(s):

Margaretha K. S. Gustafsson ◽

Marianne C. Wikgren

Keyword(s):

Neurosecretory Cells ◽

Final Host ◽

Fish Host ◽

Neurosecretory System ◽

Weak Reaction ◽

Diphyllobothrium Dendriticum ◽

Large Numbers ◽

Short Times

SUMMARYThe activation of the peptidergic neurosecretory system in Diphyllobothrium dendriticum was studied following cultivation of plerocercoids for short times in vitro and in vivo. In the plerocercoid the neurosecretory cells gave a very weak reaction with paraldehyde fuchsin (PAF). After cultivation for 1 h large numbers of neurosecretory cells filled with PAF-positive granules were evident. The significance of the activation of the neurosecretory system during the transfer of the worm from the cold-blooded fish host to the warm-blooded final host is discussed.

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Regulation of rat magnocellular neurosecretory system by D-aspartate: evidence for biological role(s) of a naturally occurring free D-amino acid in mammals

Journal of Endocrinology ◽

10.1677/joe.0.1670247 ◽

2000 ◽

Vol 167 (2) ◽

pp. 247-252 ◽

Cited By ~ 57

Author(s):

H Wang ◽

H Wolosker ◽

J Pevsner ◽

SH Snyder ◽

DJ Selkoe

Keyword(s):

Gene Expression ◽

Amino Acids ◽

Amino Acid ◽

Physiological Function ◽

Neurosecretory System ◽

Milk Ejection ◽

Magnocellular Neurons ◽

Rat Hypothalamus ◽

Naturally Occurring

Little evidence is available for the physiological function of D-amino acids in species other than bacteria. Here we demonstrate that naturally occurring freed -aspartate (D-Asp) is present in all magnocellular neurons of rat hypothalamus. The levels of this naturally occurring D-amino acid were elevated during lactation and returned to normal thereafter in the magnocellular neurosecretory system, which produces oxytocin, a hormone responsible for milk ejection during lactation. Intraperitoneal injections of D-Asp reproducibly increased oxytocin gene expression and decreased the concentration of circulating oxytocin in vivo. Similar changes were observed in the vasopressin system. These results provide evidence for the role(s) of naturally occurring free D-Asp in mammalian physiology. The findings argue against the conventional concept that only L-stereoisomers of amino acids are functional in higher species.

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Fish caudal neurosecretory system: A model for the study of neuroendocrine secretion

General and Comparative Endocrinology ◽

10.1016/j.ygcen.2006.12.027 ◽

2007 ◽

Vol 153 (1-3) ◽

pp. 243-250 ◽

Cited By ~ 22

Author(s):

Catherine R. McCrohan ◽

Weiqun Lu ◽

Matthew J. Brierley ◽

Louise Dow ◽

Richard J. Balment

Keyword(s):

Neurosecretory System ◽

Caudal Neurosecretory System ◽

System A

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Histochemical Studies on the Hypothalamo-hypophysial Neurosecretory System. II. PAS Reaction in the Freeze-dried Section

Archivum histologicum japonicum ◽

10.1679/aohc1950.13.487 ◽

1957 ◽

Vol 13 (4) ◽

pp. 487-490 ◽

Cited By ~ 1

Author(s):

Teruo IMOTO

Keyword(s):

Neurosecretory System ◽

Freeze Dried ◽

Pas Reaction

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MALFORMED CAUDAL NEUROSECRETORY SYSTEM IN THE EEL,ANGUILLA JAPONICA

Embryologia ◽

10.1111/j.1440-169x.1965.tb00217.x ◽

1965 ◽

Vol 9 (1) ◽

pp. 78-97 ◽

Cited By ~ 7

Author(s):

KATSUTOSHI IMAI

Keyword(s):

Anguilla Japonica ◽

Neurosecretory System ◽

Caudal Neurosecretory System

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The Larval Eclosion Hormone Neurones in Manduca Sexta: Identification of the Brain-Proctodeal Neurosecretory System

Journal of Experimental Biology ◽

10.1242/jeb.147.1.457 ◽

1989 ◽

Vol 147 (1) ◽

pp. 457-470 ◽

Cited By ~ 4

Author(s):

JAMES W. TRUMAN ◽

PHILIP F. COPENHAVER

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Manduca Sexta ◽

Nerve Cord ◽

Release Site ◽

Neurosecretory System ◽

Nerve Activity ◽

Eclosion Hormone ◽

The Central Nervous System ◽

The Brain

Larval and pupal ecdyses of the moth Manduca sexta are triggered by eclosion hormone (EH) released from the ventral nervous system. The major store of EH activity in the latter resides in the proctodeal nerves that extend along the larval hindgut. At pupal ecdysis, the proctodeal nerves show a 90% depletion of stored activity, suggesting that they are the major release site for the circulating EH that causes ecdysis. Surgical experiments involving the transection of the nerve cord or removal of parts of the brain showed that the proctodeal nerve activity originates from the brain. Retrograde and anterograde cobalt fills and immunocytochemistry using antibodies against EH revealed two pairs of neurons that reside in the ventromedial region of the brain and whose axons travel ipsilaterally along the length of the central nervous system (CNS) and project into the proctodeal nerve, where they show varicose release sites. These neurons constitute a novel neuroendocrine pathway in insects which appears to be dedicated solely to the release of EH.

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